Plant Morphology and Taxonomy of Angiosperm Chapter Taxonomy and 5 Systematic Botany

Home , Asteridea (plant), Buxales, Cestrum diurnum, Crotalaria juncea, Crotalaria verrucosa, Dilleniales

Unit II: Plant Morphology and Taxonomy of Angiosperm Chapter Taxonomy and 5 Systematic Botany

Plants are the prime companions of human Learning Objectives beings in this universe. Plants are the The learner will be able to, source of food, energy, shelter, clothing, drugs, beverages, oxygen and the aesthetic • Differentiate systematic botany from taxonomy. environment. Taxonomic activity of human • Explain the ICN principles and to is not restricted to living organisms alone. discuss the codes of nomenclature. Human beings learn to identify, describe, • Compare the national and international name and classify food, clothes, books, herbaria. games, vehicles and other objects that they • Appreciate the role of morphology, come across in their life. Every human being anatomy, cytology, DNA sequencing in thus is a taxonomist from the cradle to the relation to Taxonomy, grave. • Describe diagnostic features of Taxonomy has witnessed various families Fabaceae, Solanaceae and phases in its early history to the present day Liliaceae. modernization. The need for knowledge on plants had been realized since human existence, a man started utilizing plants Chapter Outline for food, shelter and as curative agent for 5.1 Taxonomy and Systematics ailments. 5.2 Taxonomic Hierarchy Theophrastus (372 – 287 BC), the 5.3 Concept of species – Morphological, Greek Philosopher known as “Father of Biological and Phylogenetic Botany”. He named and described some 500 5.4 International Code of plants in his “De Historia Plantarum”. Later Botanical Nomenclature Dioscorides (62 – 127 AD), Greek physician, 5.5 Taxonomic Aids described and illustrated in his famous 5.6 Botanical Gardens “Materia medica” and described about 600 5.7 Herbarium – Preparation and uses medicinal plants. From 16th century onwards 5.8 Classification of Plants Europe has witnessed a major developments 5.9 Need for classification in the field of Taxonomy. Some of the key 5.10 Types of classification contributors include Andrea Caesalpino, John 5.11 Modern trends Ray, Tournefort, Jean Bauhin and Gaspard in taxonomy Bauhin. Linnaeus ‘Species Plantarum' (1753) 5.12 Cladistics laid strong foundation for the binomial nomenclature. 5.13 Selected Families Taxonomy is no more classical morphology of Angiosperms based discipline but become a dynamic

XIth_BIO-BOTANY_Ch_5-EM.indd 86 5/17/2020 11:17:47 PM and transdisciplinary subject, making use classification including the bases, principles, of many branches of botany such as Cell rules and procedures”. Biology, Physiology, Biochemistry, Ecology, Simpson (1961) defined Systematics as, Pharmacology and also Modern Biotechnology, “Scientific study of the kinds and diversity of Molecular Biology and Bioinformatics. It organisms and all relationships among them”. helps to understand biodiversity, wildlife, Though there are two terms are used in an forest management of natural resources for interchangeable way, they differ from each sustainable use of plants and eco restoration. other. 5.1 Taxonomy and Systematics 5.2 Taxonomic Hierarchy The word taxonomy is derived from Greek Taxonomic hierarchy was introduced by words “taxis” (arrangement) and “nomos” Carolus Linnaeus. It is the arrangement of (rules or laws). Taxonomy is defined as various taxonomic levels in descending order as “the science dealing with the study of starting from kingdom up to species. Differences between Taxonomy and Systematics Taxonomy Systematics • Discipline of classifying organisms into • Broad field of biology that studies the taxa. diversification of species. • Governs the practices of naming, • Governs the evolutionary history and describing, identifying and specimen phylogenetic relationship in addition to preservation. taxonomy. • Classification + Nomenclature = • Taxonomy + Phylogeny = Systematics Taxonomy Species is the lowest of classification and Kingdom is the highest level or rank of the shows the high level of similarities among the classification. Example: Plantae organisms. For example, Helianthus annuus Rank Ending Example and Helianthus tuberosus. These two species Kingdom - Plantae differ in their morphology. Both of them are Phylum = -phyta Magnoliophyta herbs but Helianthus tuberosus is a perennial Division herb. Subphylum = -phytina Magnoliophytina Genus consists of multiple species which Sub division have similar characters but differ from the Class -opsida Asteropsida species of another genus. Example: Helianthus, Sub class -idea Asteridea Tridax. Order -ales Asterales Family comprises a number of genera Suborder -ineae Asterineae which share some similarities among them. Family -aceae Asteraceae Example: Asteraceae. Sub family -oideae Asteroideae Order includes group of families which Tribe -eae Heliantheae show less similarities among them. Genus - Helianthus Helianthus subg. Class consists of group of orders which Sub genus - share few similarities. Helianthus Helianthus ser. Division is the next level of classification Series - Helianthus that consists of number of classes. Example: Magnoliophyta. Species - Helianthus annuus

XIth_BIO-BOTANY_Ch_5-EM.indd 87 5/17/2020 11:17:47 PM 5.3 Concept of species-Morphological, 5.4 International Code of Botanical Biological and Phylogenetic Nomenclature (ICBN) Species is the fundamental unit of taxonomic Assigning name for a plant is known as classification. Species is a group of individual Nomenclature. This is based on the rules organisms which have the following characters. and recommendations of the International 1. A population of organisms which closely Code of Botanical Nomenclature. ICBN resemble each other more than the other deals with the names of existing (living) and population. extinct (fossil) organisms. The elementary 2. They descend from a common ancestor. rule of naming of plants was first proposed by 3. In sexually reproducing organisms, they Linnaeus in 1751 in his Philosophia Botanica. interbreed freely in nature, producing In 1813 a detailed set of rules regarding plant fertile offspring. nomenclature was given by A.P. de Candolle Species concepts can be classified into two in his famous work “Theorie elementaire general groups. Concept emphasizing process de la botanique”. Then the present ICBN of evolution that maintains the species as a unit was evolved by following the same rules and that can result in evolutionary divergence of Linnaeus, A.P. de Candolle and his son and speciation. Another concept emphasises Alphonse de Candolle. the product of evolution in defining a species. ICBN due to specific reasons and in order to Types of Species separate plant kingdom from other organisms, There are different types of species and they are is redesignated as ICN. The International as follows: Botanical Congress held in Melbourne in July 1. Process of evolution - Biological Species 2011 brought this change. The ICN stands 2. Product of evolution - Morphological Species for International Code of Nomenclature for Algae, Fungi and Plants. and Phylogenetic Species Morphological Species (Taxonomic species) ICN Principles When the individuals are similar to one International Code of Nomenclature is based another in one or more features and different on the following six principles. from other such groups, they are called 1. Botanical nomenclature is independent morphological species. of zoological and bacteriological Biological Species (Isolation Species) nomenclature. According to Ernest Mayr 1963,“ these are 2. Application of names of taxonomic group groups of populations that interbreed and is determined by means of nomenclatural are reproductively isolated from other such types. groups in nature”. 3. Nomenclature of a taxonomic group is based on priority of publication. Phylogenetic Species 4. Each taxonomic group with a particular This concept was developed by Meglitsch circumscription, position and rank can (1954), Simpson (1961) and Wiley (1978). bear only one correct name. Wiley defined phylogenetic species as “an 5. Scientific names of taxonomic groups evolutionary species is a single lineage of are treated as Latin regardless of their ancestor descendent populations which derivation. maintains its identity from other such lineages 6. The rules of nomenclature are retroactive which has its own evolutionary tendencies unless expressly limited. and historical fate”.

XIth_BIO-BOTANY_Ch_5-EM.indd 88 5/17/2020 11:17:47 PM Codes of Nomenclature refer to more than one plant or many plants ICN has formulated a set of rules and may have same common name. These names recommendations dealing with the botanical are regional or local and are not universal. name of plants. International Botanical Example: Albizia amara . L belongs to Congress is held at different places every six Mimosaceae is called as Usilai in South years. Proposals for nomenclatural changes Tamilnadu and Thurinji in North Tamilnadu. and changes in rules are discussed and Activity implemented. Changes are published in their Write common name and scientific name of website. 10 different plants around your home. 18th International Botanical Congress held in 2011at Melbourne, Australia made Scientific Names / Botanical Names the following major changes. Each and every taxon as per the ICN (species, 1. The code now permits electronic genus, family etc) can have only one correct publication of names of new taxa. scientific name. Scientific name of a species is always a binomial. These names are 2. Latin diagnosis or description is not universally applied. Example: Oryza sativa L. mandatory and permits the use of English is the scientific name of paddy. or Latin for the publication of a new name (Art-39). Polynomial 3. “One fungus, one name” and “one fossil Polynomial is a descriptive phrase of a plant. one name” are important changes, the Example: Ranunculus calycibus retroflexis concept of anamorph and teleomorph pedunculis falcatis caule erecto folius (for fungi) and morphotaxa (for fossils) compositis. It means butter cup with reflexed have been eliminated. (Previously, sexual sepals, curved flower stalks, erect stem and and asexual stages of the fungus/ fossils compound leaves. Polynomial system of were provided with different names). naming a plant is replaced by a binomial system by Linnaeus. Anamorph – Asexual reproductive stage Binomial of fungus. Binomial nomenclature was first introduced Teleomorph – Sexual reproductive stage of by Gaspard Bauhin and it was implemented fungus. by Carolus Linnaeus. Scientific name of a 4. As an experiment with “registration of species consists of two words and according names” new fungal descriptions require to binomial nomenclature, the first one is the use of an identifier from a “recognized called genus name and second one is specific repository”. There are two recognized epithet. Example: Mangifera indica. Mangifera repositories Index fungorum and Myco is a genus name and indica is specific epithet. Bank. This system is in vogue even now. 19th International Botanical Congress was Author citation held in Shenzhen in China in 2017. Changes This refers to valid name of the taxa accepted by International Botanical Congress accompanied by the author’s name who are yet to be published. published the name validly. Example: Solanum Vernacular names (Common names) nigrum L. There are two types of author Vernacular names are known as common citation. names. They are very often descriptive and Single author: When a single author proposed poetic references to plants. Common name a valid name, the name of the author alone

XIth_BIO-BOTANY_Ch_5-EM.indd 89 5/17/2020 11:17:47 PM is accompanied by his abbreviated name. Example: Example: Pithecellobium cinereum Benth. 1. a) Flowers cream-coloured; fruiting calyx Multiple authors: When two or more authors enclosing the berry ...... Physalis are associated with a valid publication of name, b) Flowers white or violet; fruiting calyx their names should be noted with the help of not enclosing the berry ....2 Latin word et or &. 2. a) Corolla rotate; Example: Delphinium viscosum Hook. f. et fruit a berry .....Solanum Thomson. b) Corolla funnel-form or salver-form; Standard form of author’s abbreviations fruit a capsule: ....3 has to be followed. 3. a) Radical leaves present; flowers in racemes; fruits without prickles Standard form of Author ...Nicotiana Abbreviation Linnaeus L. b) Radical leaves absent; flowers solitary; fruits with G.Bentham Benth. prickles .....Datura William Hooker Hook. Another type of key for identification is Robert Brown R.Br. the Polyclave or Multi-entry key. It consists J.P.Lamarck Lamk. of a list of numerous character states. The A.P.de Candolle DC. user selects all states that match the specimen. Wallich Wall. Polyclave keys are implemented by a computer Alphonse de Candolle A. DC. 5.5 Taxonomic Aids algorithm. Taxonomic aids are the tools for the taxonomic 5.6 Botanical Gardens study. Some techniques, procedures and stored In true sense all gardens are not botanical information that are useful in identification gardens. Botanical gardens are centres and classification of organisms are called for collection of plants in their various taxonomical aids. They are required in stages of living. Gardens existed for almost all branches of biological studies for growing ornamental plants for aesthetic their proper identification and for finding value, religious and status reasons. The their relationship with others. Some of the famous “hanging gardens” of Babylon in taxonomical aids are keys, flora, revisions, Mesopotamia is an example. For the purpose monograph, catalogues, herbarium, botanical of science and education the first garden was gardens etc. maintained by Theophrastus in his public lecture hall at Athens. Keys First modern botanical garden was Taxonomic keys are the tools for the established by Luca Ghini (1490-1556) a identification of unfamiliar plants. These professor of Botany at Pisa, Italy in 1544. keys are based on characters which are stable Botanical garden contains special plant and reliable. The most common type of key is collections such as cacti, succulent, green a dichotomous key. It consists of a sequence house, shade house, tropical, alpine and of two contrasting statements. A pair of exotic plants. Worldwide there are about contrasting statements is known as couplet. 1800 botanical gardens and arboreta. Each statement is known as lead. The plant Role of Botanical Garden: Botanical is correctly identified with keys by narrowing Gardens play the following important roles. down the characters found in plant. 1. Gardens with aesthetic value which attract

XIth_BIO-BOTANY_Ch_5-EM.indd 90 5/17/2020 11:17:47 PM National Botanical Gardens

National AJCB Indian Botanical garden Botanical garden Lucknow Kolkata

Established in Established in 1948 1786 by Arboretum- Lt. Col. Robert Kyd 500 species of trees

JNTBGRI The National Trivandrum Orchidarium Kerala Yercaud Largest and 500 species Established in Established in oldest of Rose hybrids 1979 1963 Conserving Maintained by 15,000 tropical plant: Southern circle species of Genetic resources of BSI pplants 3,000 trees and 4,000 species 1,800 shrubs plants & Major Attraction- Major attraction- Insectivorous plants germ plasm collection & ex-situ conservationon Major Attraction- 300 species of The Great Banyan Tree plants

Major attraction- Bambusetum (69 species)

Figure 5.1: National Botanical Garden

XIth_BIO-BOTANY_Ch_5-EM.indd 91 5/17/2020 11:17:48 PM a large number of visitors. For example, Preparation of herbarium Specimen the Great Banyan Tree (Ficus benghalensis) Herbarium Specimen is defined as a pressed in the Indian Botanical Garden at Kolkata. and dried plant sample that is permanently 2. Gardens have a wide range of species and glued or strapped to a sheet of paper along with supply taxonomic material for botanical a documentation label. research. Preparation of herbarium specimen 3. Garden is used for self-instruction or includes the following steps. demonstration purposes. 1. Plant collection: Field collection, Liquid 4. It can integrate information of diverse preserved collection, Living collection, fields like Anatomy, Embryology, Phyto- Collection for molecular studies. chemistry, Cytology, Physiology and 2. Documentation of field site data Ecology. 3. Preparation of plant specimen 5. Act as a conservation centre for diversity, 4. Mounting herbarium specimen rare and endangered species. 5. Herbarium labels. 6. It offers annual list of available species 6. Protection of herbarium sheets against and a free exchange of seeds. mold and insects 7. Botanical garden gives information about method of propagation, sale of plant Uses of Herbarium material to the general public. 1. Herbarium provides resource material Royal Botanic garden, Kew- England for systematic research and studies. 2. It is a place for orderly arrangement of voucher specimens. 3. Voucher specimen serves as a reference for comparing doubtful newly collected fresh specimens. 4. Voucher specimens play a role in studies like floristic diversity, environmental Figure 5.2: Royal Botanic garden, Kew - England assessment, ecological mechanisms and Royal Botanic garden Kew- England is a survey of unexplored areas. non- departmental public body in the United 5. Herbarium provides opportunity for Kingdom. It is the largest botanical garden in documenting biodiversity and studies the world, established in 1760, but officially related to the field of ecology and opened in the year 1841. conservation biology. Plant collections include Aquatic garden, Kew Herbarium Arboretum with 14,000 trees, Bonsai Kew Garden is situated in South West collection, Cacti collection and Carnivorous London that houses the “largest and plant collection. most diverse botanical and mycological 5.7 Herbarium – Preparation and uses collections in the world” founded in the Herbaria are store houses of preserved plant year 1840. Living collection includes more collections. Plants are preserved in the form than 30,000 different kinds of plants. While of pressed and dried specimens mounted on herbarium which is one of the largest in a sheet of paper. Herbaria act as a centre for the world has over seven million preserved research and function as sources of material plant specimens. The library contains for systematic work. more than 7,50,000 volumes and the

XIth_BIO-BOTANY_Ch_5-EM.indd 92 5/17/2020 11:17:49 PM Preparation of herbarium Specimen

Plant Collection Plant specimen with flower or fruit is collected

Documentation of field site data Certain data are to be recorded at the time of plant collection. It includes date, time, country, state, city, specific locality information, latitude, longitude, elevation and land mark information. These data will be typed onto a herbarium label.

Preparation of plant specimen Plant specimen collected from the field is pressed immediately with the help of portable field plant press. plant specimen is transferred to a standard plant press (12” x 18”) which between two outer 12” x 18” frames and secured by two straps.

Mounting herbarium specimen The standard size of herbarium sheet is used for mounting the specimen (29cm x 41cm). specimens are affixed to herbarium sheet with standard white glue or solution of Methyl cellulose.

Herbarium label Herbarium label size is generally 4-5’’ wide and 2-3’’ tall. A typical label contains all information like habit, habitat, vegetation type, land mark information, latitude, longitude, image document, collection number, date of collection and name of the collector. World’s smallest water – lily Nymphaea Protection of herbarium sheets against thermarum was saved mold and insects Apply cation of 2% Mercuric chloride, f r o m Naphthalene, DDT, carbon disulphide. Fu- extinction when it was migation using formaldehyde. Presently deep grown from seed at Kew freezing(-20oC) method is followed throughout the world. in 2009.

XIth_BIO-BOTANY_Ch_5-EM.indd 93 5/17/2020 11:17:52 PM International Herbarium Number of S.No Herbarium Year Established Acronym specimens 1. Museum National d’Histoire Naturelle, Paris, 1635 P ,PC 10,000,000 France 2. New York Botanical Garden, Bronx, New 1891 NY 72,00,000 York, U.S.A 3. Komarov Botanical Institute, St.Petersburg 1823 LE 71,60,000 (Leningrad), Russia 4. Royal Botanic Gardens, Kew, England, U.K 1841 K 70,00,000

National Herbarium Number of S.No Herbarium Year Established Acronym specimens 1. Madras Herbarium 1955 MH 4,08,776 BSI campus, Coimbatore 2. Central National Herbarium 1795 CAL 2,00,000 West Bengal 3. Jawaharlal Nehru Tropical Botanical 1979 TBGRI 30,500 Garden and Research Institute Thiruvananthapuram, Kerala 4. Presidency College Herbarium, Chennai. 1844 PCM 15,000

illustrations and also a collection of more Similarly there is a vast assemblage of than 1,75,000 prints, books, photographs, group of plants in the world. Is it possible letters, manuscripts, periodicals, maps and to study and understand all of these? No. botanical illustrations. Since it is difficult to study all these plants together, it is necessary to device some 5.8 Classification of Plants means to make this possible. Imagine walking into a library and looking for a Harry Potter story book. Classification is essential to biology As you walk into the library you notice because there is a vast diversity of that it is under renovation and all the organisms to sort out and compare. books are scattered. Will it not be hard Unless they are organized into manageable to find the exact book you are looking categories it will be difficult for for? It might take hours. So you decide identification. Biological classifications are to come the next day when all the books the inventions of biologists based upon the are arranged according to the genres. One best evidence available. The scientific basis rack for adventure, another for Detective, for cataloguing and retrieving information Fantasy, Horror, Encyclopaedia and so about the tremendous diversity of flora is on. You automatically know Harry Potter known as classification. is in the fantasy section and it takes less Classification paves way for the than ten minutes for you to find it. That arrangement of organisms into groups on the is because the books have been classified basis of their similarities, dissimilarities and and arranged according to a system. relationships. The purpose of classification is to provide a systematic arrangement

XIth_BIO-BOTANY_Ch_5-EM.indd 94 5/17/2020 11:17:52 PM Botanical Survey of India 5.10 Types of classification Taxonomic entities are classified in three On 13 February 1890, a survey was ways. They are artificial classification, formally constituted and designated natural classification and phylogenetic as the Botanical Survey of India. After classification. independence, the need was felt for a more comprehensive documentation of 5.10.1 Artificial system of classification the country’s plant resources to boost the 24 classes recognized by Linnaeus in his economy. Padmashree Dr.E.K.Janaki Species Plantarum (1753) on the basis of Ammal was appointed as officer on stamens. special Duty on 14th Oct 1952. Then No. Classes Characters reorganization plan was finally approved 1 Monandria stamen one by the Govt. of India on 29 March 1954, 2 Diandria stamens two with Calcutta as the headquarters of BSI. Jammu Tavi Botanical Garden has been 3 Triandria stamens three named after Dr. E. K. Janaki Ammal. 4 Tetrandria stamens four 5 Pentandria stamens five up to 24th class flowerless plants Cryptogamia Carolus Linnaeus (1707 -1778) was a great Swedish Botanist and said to be the “Father of Taxonomy.” He outlined an artificial system Figure 5.3: Dr. E.K. Janaki Ammal of classification in “Species Plantarum” expressing the relationship between the in 1753, wherein he organisms. listed and described Taxonomists have assigned a method of 7,300 species and classifying organisms which are called ranks. arranged in 24 These taxonomical ranks are hierarchical. classes mostly on the basis of number, Figure 5.4: The scheme of classification has to be flexible, Carolus Linnaeus allowing newly discovered living organisms union (adhesion to be added where they fit best. and cohesion), length, and distribution of stamens. The classes were further subdivided 5.9 Need for Classification on the basis of carpel characteristics into • Understanding the classification of orders. Hence the system of classification organisms can give an insight into other is also known as sexual system of fields and has significant practical value. classification. • Classification helps us to know about This system of classification though different taxa, their phylogenetic artificial, was continued for more than relationship and exact position. 100 years after the death of Linnaeus, due to • It helps to train the students of plant its simplicity and easy way of identification sciences with regard to the diversity of of plants. organisms and their relationship with However the system could not hold good other biological branches. due to the following reasons.

XIth_BIO-BOTANY_Ch_5-EM.indd 95 5/17/2020 11:17:52 PM 1. Totally unrelated plants were kept in a 97,205 species. In this system the seeded single group, whereas closely related plants plants were classified into 3 major classes were placed in widely separated groups. such as Dicotyledonae, Gymnospermae and Example: Monocotyledonae. a. Zingiberaceae of monocotyledons and Class I Dicotyledonae: Plants contain Anacardiaceae of dicotyledonous were two cotyledons in their seed, leaves with placed under the class Monandria reticulate venation, tap root system and since these possess single stamens. tetramerous or pentamerous flowers come b. Prunus was classified along with Cactus under this class. It includes three sub- because of the same number of stamens. classes – Polypetalae, Gamopetalae and Monochlamydeae. No attempts were made to classify plants based on either natural or phylogenetic Sub-class 1. Polypetalae: Plants with relationships which exist among plant free petals and dichlamydeous flowers come groups. under polypetalae. It is further divided into three series – Thalamiflorae, Disciflorae 5.10.2 Natural system and Calyciflorae. Botanists who came after Linnaeus realised Series (i) Thalamiflorae: Plants having that no single character is more important flowers with dome or conical shaped than the other characters. Accordingly an thalamus and superior ovary are included approach to a natural system of classification in this series. It includes 6 orders and 34 sprouted in France. The first scheme of families. classification based on overall similarities Series (ii) Disciflorae: Flowers having was presented by Antoine Laurent de prominent disc shaped thalamus with Jessieu in 1789. superior ovary come under this series. It Bentham and Hooker system of includes 4 orders and 23 families. classification Series (iii) Calyciflorae: It includes plants having flowers with cup shaped thalamus and with inferior or sometimes with half inferior ovary. Calyciflorae includes 5 orders and 27 families. Sub-class 2. Gamopetalae: Plants with united petals, which are either partially or completely fused to one another and dichlamydeous are placed under Gamopetalae. It is further divided into Figure 5.5: George Bentham and J.D. Hooker three series – Inferae, Heteromerae and Bicarpellatae. A widely followed natural system of Series (i) Inferae: The flowers are classification considered the best was epigynous and with inferior ovary. Inferae proposed by two English botanist George includes 3 orders and 9 families. Bentham (1800 – 1884) and Joseph Dalton Series (ii) Heteromerae: The flowers are Hooker (1817–1911). The classification hypogynous, superior ovary and with more was published in a three volume work than two carpels. Heteromerae includes 3 as “Genera Plantarum” (1862–1883) orders and 12 families. describing 202 families and 7569 genera and

XIth_BIO-BOTANY_Ch_5-EM.indd 96 5/17/2020 11:17:52 PM Seed plants

Class I Class II Class III Dicotyledonae Gymnospermae Monocotyledonae 3 families 7series and 34 families 1. Gnetaceae 2. Coniferae 3. Cycadaceae

Sub-classI Sub-class II Sub-class III Polypetalae Gamopetalae Monochlamydeae 8 series and 36 families Series (i) Thalamiflorae Series (i) Inferae 6 orders and 34 families 3 orders and 9 families

Series (ii) Disciflorae Series (ii) Heteromerae 4orders and 23 families 3 orders and 12 families

Series (iii) Calyciflorae Series (iii) Bicarpellatae 5orders and 27 families 4 orders and 24 families

Figure 5.6: Bentham and Hooker system of classification

Series (iii) Bicarpellatae: The flowers The Bentham and Hooker system of are hypogynous, superior ovary and with classification is still supposed to be the best two carpels. Bicarpellatae includes 4 orders system of classification. It has been widely and 24 families. practiced in colonial countries and herbaria Sub-class 3. Monochlamydeae: Plants of those countries were organised based on with incomplete flowers either apetalous or this system and is still used as a key for the with undifferentiated calyx and corolla are identification of plants in some herbaria of the placed under Monochlamydeae. The sepals world due to the following reasons: and petals are not distinguished and they are • Description of plants is quite accurate called perianth. Sometimes both the whorls and reliable, because it is mainly based on are absent. Monochlamydeae includes 8 series personal studies from actual specimens and 36 families. and not mere comparisons of known facts. Class II Gymnospermae: Plants that • As it is easy to follow, it is used as a key contain naked seeds come under this class. for the identification of plants in several Gymnospermae includes three families – herbaria of the world. Gnetaceae, Coniferae and Cycadaceae. Though it is a natural system, this system Class III Monocotyledonae: Plants was not intended to be phylogenetic. contain only one cotyledon in their seed, 5.10.3 Phylogenetic system of classification leaves with parallel venation, fibrous root The publication of the Origin of Species system and trimerous flowers come under (1859) by Charles Darwin has given stimulus this class. The Monocotyledonae has 7 series for the emergence of phylogenetic system of and 34 families. classification.

XIth_BIO-BOTANY_Ch_5-EM.indd 97 5/17/2020 11:17:52 PM I Adolph Engler and Karl A Prantl system based on a wide range of classification of taxonomic characters including anatomical and phytochemical characters of phylogenetic importance. He has presented his classification in 1968 in his Figure 5.9: Arthur Cronquist book titled “The evolution and classification of flowering plants.” Hi s Figure 5.7: Adolph Engler and Karl A Prantl classification is broadly based on the Principles One of the earliest phylogenetic system of of phylogeny that finds acceptance with major classification of the entire plant Kingdom was contemporary authors. jointly proposed by two German botanists Cronquist classified the angiosperms Adolph Engler ( 1844 -1930) and Karl A into two main classes Magnoliopsida Prantl (1849 - 1893). They published their (=dicotyledons) and Liliopsida classification in a monumental work “Die (= monocotyledons). There are 6 subclasses, Naturelichen Pflanzen Familien” in 23 64 orders, 320 families and about 165,000 volumes (1887-1915) species in Magnoliopsida, whereas in In this system of classification the plant Liliopsida there are 5 sub classes, 19 orders, kingdom was divided into 13 divisions. The 66 families and about 50,000 species. first 11 divisions are Thallophytes, twelfth Cronquist system of classification also division is Embryophyta Asiphonogama could not persist for a long time because, the (plants with embryos but no pollen tubes; system is not very useful for identification Bryophytes and Pteridophytes) and the and cannot be adopted in herbaria due to its thirteenth division is Embryophyta high phylogenetic nature. Siphonogama (plants with embryos and pollen tubes) which includes seed plants. 5.10.4 Angiosperm phylogeny group II Arthur Cronquist system of classification (APG) classification Arthur Cronquist (1919 - 1992) an The most recent classification of flowering plants based on phylogenetic data was set eminent American taxonomist proposed in the last decade of twentieth century. Four phylogenetic classification of flowering plants versions of Angiosperm Phylogenetic Group classification (APG I, APG II, APG III & Division: Embryophyta (Siphonogama) APG IV) have been published in 1998, 2003, 2009 and 2016 Sub-division: Gymnospermae Sub-division: Angiospermae respectively. Each version supplants the previous version. Recognition of monophyletic group based Class: Monocotyledonae Class: Dicotyledonae (includes 11 orders 45 families) (includes 44 orders) on the information received from various disciplines such Archichlamydeae Metachlamydeae as gross morphology, anatomy, (Apetalae) (Sympetalae) embryology, palynology, karyology, (i) Corolla polypetalous (i) Corolla Gamopetalous (ii) Perianth single or double (ii) Perianth in two whorls phytochemistry and more strongly (iii) Includes 33 orders 201 families (iii) Includes 11 orders 57 families on molecular data with respect to Figure 5.8: Outline of Engler and Prantl classification DNA sequences of two chloroplast

XIth_BIO-BOTANY_Ch_5-EM.indd 98 5/17/2020 11:17:53 PM ) Rosidae (5) (6

Asteridae 4. Zingiberidae

3. Commelinidae 5. Lilidae Dilleniidae (4) Hamamelidae (2) s

Magnoliidae Caryophyllidae (3) 2. Arecidae (1) Sub-clas

1. Alismatidae Sub-class

Class: Magnoliopsida Class: Liliopsida

Figure 5.10: Diagramatic representation of class Magnoliopsida and Liliopsida. genes (atpB and rbcL) and one nuclear gene Amborellales (nuclear ribosomal 18s DNA). The most recent updated version, APG Nymphaeales IV (2016) recognised 64 orders and 416 Austrobaileyales

families. Of these, 416 families 259 are EARLY Magnoliids

represented in India. ANGIOSPERMS Chloranthales The outline of APG IV classification is MONOCOTS Monocots Musaceae Family: Liliaceae given below. Ceratophyllales Angiosperms are classified into three Ranunculales clades early angiosperms, monocots and Proteales eudicots. Early angiosperms are classified EUDICOTS Torchodendrales

into 8 orders and 26 families (ANA- Early Buxales eudicots clade + magnoliids + Chloranthales) diverging Gunnerales Amborellales Dilleniales Nymphaeales Saxifragales Austrobaileyales Rosids Super rosids Fabaceae Family: Euphorbiaceae ➢ Seeds generally always with two Berberidopsidales cotyledons. Santalales

➢ Presence of ethereal oils. Super Caryophyllales asterids ➢ Leaves are always simple net-veined. Asterids Apocynaceae ➢ Each floral whorls with many parts. Family: Solanaceae ➢ Perianth usually spirally arranged or Figure 5.11: Simplified version of APG IV parts in threes. (Source: Plant Gateway's The Global Flora, Vol. I January 2018) ➢ Stamens with broad filaments. ➢ Anthers tetrasporangiate. Monocots are classified into 11 orders ➢ Pollen monosulcate. and 77 families (basal monocots + lilioids + ➢ Nectaries are rare. commelinids) ➢ Carpels usually free and ➢ Seeds with single cotyledon. ➢ Embryo very small. ➢ Primary root short-lived.

XIth_BIO-BOTANY_Ch_5-EM.indd 99 5/17/2020 11:17:53 PM Families 386462 457413 416202303

Bentham and Engler and Arthur Cronquist APG I APG II APG III APG IV Hooker 1883 Prantl1915 1981 1998 2003 2009 2016 Figure 5.12: A timeline showing the history of classifying flowering plants into families. ( Source: Royal Botanic Gardens Kew State of World's Plant 2017 )

➢ Single adaxial prophyll. Classification reflects the state of our ➢ Ethereal oils rarely present. knowledge at a given point of time. It will ➢ Mostly herbaceous, absence of vascular continue to change as we acquire new cambium. information. ➢ Vascular bundles are scattered in the stem. A significant number of ➢ Leaf simple with parallel-veined. major herbaria, including ➢ Floral parts usually in threes. Kew are changing the ➢ Perianth often composed of tepals. order of their collections ➢ Pollen monosulcate. in accordance with APG. ➢ Styles normally hollow and The influential world checklist of ➢ Successive microsporogenesis. selected plant families (also from kew) is Eudicots are divided into 45 orders and 313 being updated to the APG III system. families (early diverging eudicots + super A recent photographic survey of the plants of USA and Canada is organized rosids + super asterids). according to the APG III system. ➢ Seeds with always two cotyledons. In UK, the latest edition of the standard ➢ Nodes trilacunar with three leaf traces. flora of the British Isles written by Stace is ➢ Stomata anomocytic. based on the APG III system. ➢ Ethereal oils rarely present. ➢ Woody or herbaceous plants. 5.11 Modern trends in taxonomy ➢ Leaves simple or compound, usually net- Taxonomists now accept that, the veined. morphological characters alone should not ➢ Flower parts mostly in twos, fours or be considered in systematic classification fives. of plants. The complete knowledge of ➢ Microsporogenesis simultaneous. taxonomy is possible with the principles of ➢ Style solid and various disciplines like Cytology, Genetics, ➢ Pollen tricolpate. Anatomy, Physiology, Geographical APG system is an evolving system that Distribution, Embryology, Ecology, might undergo change periodically based on Palynology, Phenology, Bio-Chemistry, the new sets of data from various disciplines Numerical Taxonomy and Transplant of Botany. It is the currently accepted system Experiments. These have been found to be across the world and followed by all the useful in solving some of the taxonomical leading taxonomic institutions and practising problems by providing additional taxonomists. However, it is yet to percolate characters. It has changed the face of into the Indian botanical curriculum. classification from alpha (classical) to omega

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XIth_BIO-BOTANY_Ch_5-EM.indd 100 5/17/2020 11:17:53 PM (modern kind). Thus the new systematic 3. To involve any type of data gathering has evolved into a better taxonomy. based on modern concepts and not only 5.11.1 Chemotaxonomy on morphology and anatomy. Proteins, amino acids, nucleic acids, peptides 4. To recognize the various groups as separate etc. are the most studied chemicals in biosystematic categories such as ecotypes, chemotaxonomy. Chemotaxonomy is the ecospecies, cenospecies and comparium. scientific approach of classification of plants 5.11.3 Karyotaxonomy on the basis of their biochemical constituents. Chromosomes are the carriers of genetic As proteins are more closely controlled by information. Increased knowledge about the genes and less subjected to natural selection, chromosomes have been used for extensive it has been used at all hierarchical levels biosystematic studies and resolving many of classification starting from the rank of taxonomic problems. Utilization of the ‘variety’ up to the rank of division in plants. characters and phenomena of cytology for the The chemical characters can be divided explanation of taxonomic problem is known into three main categories. as cytotaxonomy or karyotaxonomy. The 1. Easily visible characters like starch characters of chromosome such as number, grains, silica. size, morphology and behaviour during 2. Characters detected by chemical tests meiosis have proved to be of taxonomic value. like phenolics, oil, fats, waxes. 5.11.4 Serotaxonomy (Immunotaxonomy) 3. Proteins. Systematic serology or serotaxonomy had its Aims of chemotaxonomy origin towards the end of twentieth century 1. To develop taxonomic characters with the discovery of serological reactions and which may improve existing system development of the discipline of immunology. of plant classification. The classification of very similar plants by 2. To improve present day knowledge of means of differences in the proteins they phylogeny of plants. contain, to solve taxonomic problems is 5.11.2 Biosystematics called serotaxonomy. Smith (1976) defined Biosystematics is an “Experimental, it as “the study of the origins and properties ecological and cytotaxonomy” through of antisera.” which life forms are studied and their Importance of serotaxonomy relationships are defined. The term It determines the degree of similarity between biosystematics was introduced by Camp species, genera, families etc. by comparing the and Gilly in 1943. Many authors feel reactions of antigens from various plant taxa Biosystematics is closer to Cytogenetics and with antibodies raised against the antigen of Ecology and much importance given not to a given taxon. classification but to evolution. Example: 1. The assignment ofPhaseolus Aims of biosystematics aureus and P. mungo to the genus Vigna is The aims of biosystematics are as follows: strongly supported by serological evidence 1. To delimit the naturally occurring biotic by Chrispeels and Gartner. community of plant species. 5.11.5 Molecular taxonomy (molecular 2. To establish the evolution of a group of systematics / molecular phylogenetics) taxa by understanding the evolutionary Molecular Taxonomy is the branch of and phylogenetic trends. phylogeny that analyses hereditary molecular

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XIth_BIO-BOTANY_Ch_5-EM.indd 101 5/17/2020 11:17:54 PM differences, mainly in DNA sequences, to nucleotide sequence due to the action of gain information and to establish genetic restriction enzymes. relationship between the members of AFLP is largely used for population different taxonomic categories. The advent of genetics studies, but has been used in studies of DNA cloning and sequencing methods have closely related species and even in some cases, contributed immensely to the development of for higher level cladistic analysis. molecular taxonomy and population genetics over the years. These modern methods Random Amplified Polymorphic DNA (RAPD) have revolutionised the field of molecular It is a method to identify genetic markers using taxonomy and population genetics with a randomly synthesized primer that will anneal improved analytical power and precision. (recombine (DNA) in the double stranded The results of a molecular phylogenetic form) to complementary regions located in analysis are expressed in the form of a tree various locations of isolated DNA. If another called phylogenetic tree. Different molecular complementary site is present on the opposing markers like allozymes, mitochondrial DNA, DNA strand at a distance that is not too great microsatellites, RFLP (Restriction Fragment (within the limits of PCR) then the reaction Length Polymorphism), RAPD (Random will amplify this region of DNA. amplified polymorphic DNA), AFLPs RAPDs like microsatellites may often be (Amplified Fragment Length Polymorphism), used for genetic studies within species but may single nucleotide polymorphism- (SNP), also be successfully employed in phylogenetic microchips or arrays are used in analysis. studies to address relationships within a species Uses of molecular taxonomy or between closely related species. However 1. Molecular taxonomy helps in establishing RAPD analysis has the major disadvantage the relationship of different plant groups that results are difficult to replicate and in that at DNA level. the homology of similar bands in different taxa 2. It unlocks the treasure chest of information may be nuclear. on evolutionary history of organisms. Significance of Molecular Taxonomy 1. It helps to identify a very large number of RFLP (Restriction Fragment Length species of plants and animals by the use of Polymorphism) conserved molecular sequences. RFLPs is a molecular method of genetic 2. Using DNA data evolutionary patterns of analysis that allows identification of taxa biodiversity are now investigated. based on unique patterns of restriction sites in specific regions of DNA. It refers 3. DNA taxonomy plays a vital role in to differences between taxa in restriction phytogeography, which ultimately helps sites and therefore the lengths of fragments in genome mapping and biodiversity of DNA following cleavage with restriction conservation. enzymes. 4. DNA- based molecular markers used for designing DNA based molecular probes, Amplified Fragment Length Polymorphism have also been developed under the branch (AFLP) of molecular systematics. This method is similar to that of identifying RFLPs in that a restriction enzyme is used 5.11.6 DNA Barcoding to cut DNA into numerous smaller pieces, Have you seen how scanners are used in each of which terminates in a characteristic supermarkets to distinguish the Universal

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XIth_BIO-BOTANY_Ch_5-EM.indd 102 5/17/2020 11:17:54 PM Product Code (UPC)? In the same way Classical Taxonomy Modern Taxonomy we can also distinguish one species from Classification is Classification is based another. DNA barcoding is a taxonomic mainly based on on morphological, re- method that uses a very short genetic morphological productive characters sequence from a standard part of a genome. characters and phylogenetic (evolutionary) relationship The genetic sequence used to identify a of the organism plant is known as “DNA tags” or “DNA This system is based This system is based barcodes”. Paul Hebert in 2003 proposed on the observation of a on the observation of ‘DNA barcoding’ and he is considered as few samples/ large number of sam- ‘Father of barcoding’. individuals ples/individuals The gene region that is being used as an effective barcode in plants is present in two 5.12 Cladistics genes of the chloroplast, matK and rbcL, and Analysis of the taxonomic have been approved as the barcode regions data, and the types of for plants. characters that are used in classification have changed Sequence of unknown species can from time to time. Plants be matched from submitted sequence in have been classified based GenBank using Blast (web-programme for on the morphology before the advancement searching the closely related sequence). of microscopes, which help in the inclusions Significance of DNA barcoding of sub microscopic and microscopic features. 1. DNA barcoding greatly helps in A closer study is necessary while classifying identification and classification of closely related plants. Discovery of new finer organism. molecular analytical techniques coupled with 2. It aids in mapping the extent of advanced software and computers has ushered biodiversity. in a new era of modern or phylogenetic classification. DNA barcoding techniques require a The method of classifying organisms into large database of sequences for comparison monophyletic group of a common ancestor and prior knowledge of the barcoding region. based on shared apomorphic characters However, DNA barcoding is a helpful tool is called cladistics (from Greek, klados- to determine the authenticity of botanical branch). material in whole, cut or powdered form. The outcome of a cladistic analysis is 5.11.7 Differences between classical and a cladogram, a tree-shaped diagram that modern taxonomy represent the best hypothesis of phylogenetic relationships. Earlier generated cladograms Classical Taxonomy Modern Taxonomy were largely on the basis of morphological It is called old It is called characters, but now genetic sequencing data systematics or Alpha Neosystematics or (ἀ) taxonomy or Biosystematics or and computational softwares are commonly Taxonomy Omega (Ω) taxonomy used in phylogenetic analysis. It is pre Darwinean It is post Darwinean Cladistic analysis species is considered Cladistics is one of the primary methods of Species is considered as as dynamic entity and basic unit and is static constructing phylogenies, or evolutionary ever changing histories. Cladistics uses shared, derived

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XIth_BIO-BOTANY_Ch_5-EM.indd 103 5/17/2020 11:17:54 PM characters to group organisms into clades. Need for cladistics These clades have atleast one shared, derived 1. Cladistics is now the most commonly character found in their most recent common used and accepted method for creating ancestor that is not found in other groups phylogenetic system of classifications. hence they are considered more closely related 2. Cladistics produces a hypothesis about to each other. These shared characters can be the relationship of organisms to predict morphological such as, leaf, flower, fruit, seed the phylogeny and so on; behavioural, like opening of flowers 3. Cladistics helps to elucidate mechanism nocturnal/diurnal; molecular like, DNA or of evolution. protein sequence and more. Cladistics accept only monophyletic 5.13 Selected Families of Angiosperms groups. Paraphyletic and polyphyletic taxa Dicot Families are occasionally considered when such taxa 5.13.1 Family: Fabaceae (Pea family) conveniently treated as one group for practical Systematic position purposes. Example: dicots, sterculiaceae. Bentham and Hooker Polyphyletic groups are rejected by cladistics. APG classification classification i. Monophyletic group; Taxa comprising Kingdom Plantae Kingdom Plantae all the descendants of a common Angio- Clade Class Dicotyledonae ancestor. sperms Clade Eudicots Sub-class Polypetalae C A D B Clade Rosids Series Calyciflorae Order Fabales Order Rosales Family Fabaceae Family Fabaceae

General characters Distribution: Fabaceae includes about 741 ii. Paraphyletic group; Taxon that genera and more than 20,200 species. The includes an ancestor but not all of the members are cosmopolitan in distribution descendants of that ancestor. but abundant in tropical and subtropical A C B D regions. Habit: All types of habits are represented CB, CBD in this family. Mostly herbs (Crotalaria), and ACB are prostrate (Indigofera enneaphylla) erect paraphyletic (Crotalaria verrucosa), shrubs (Cajanus group cajan), small trees (Sesbania), climbers (Clitoria), large tree (Pongamia, Dalbergia), iii. Polyphyletic group; Taxa that woody climber (Mucuna), hydrophyte includes members from two different (Aeschynomene aspera) lineages. commonly called C A D B W X Z Y pith plant. Root: Tap root system, roots are nodulated, have tubercles containing Root nodule

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XIth_BIO-BOTANY_Ch_5-EM.indd 104 5/17/2020 11:17:54 PM nitrogen – fixing bacteria (Rhizobium Gynoecium: Monocarpellary, unilocular, leguminosarum) ovary superior, with two alternating rows of Stem: Aerial, herbaceous, woody ovules on marginal placentation. Style simple (Dalbergia) twining or climbing (Clitoria). and bent, stigma flattened or feathery. Leaf: Leaf simple or unifoliate Fruit: The characteristic fruit of Fabaceae (Desmodium gangeticum) bifoliate (Zornia is a legume (Pisum sativum), sometimes diphylla,), Trifoliate (Lablab purpureus), indehiscent and rarely a lomentum alternate, stipulate, leaf base, pulvinate, (Desmodium). In Arachis hypogea the fruit reticulate venation terminal leaflet modifies is geocarpic (fruits develops and matures into a tendril in Pisum sativum. under the soil). After fertilization the stipe Inflorescence: Raceme (Crotalaria of the ovary becomes meristematic and verrucosa), panicle (Dalbergia latifolia) grows down into the soil. This ovary gets axillary solitary (Clitoria ternatea) buried into the soil and develops into fruit. Flowers: Bracteate, bracteolate, Seed: Endospermic or non-endospermic pedicellete, complete, bisexual, pentamerous, (Pisum sativum), mostly reniform. heterochlamydeous, zygomorphic Botanical description of Clitoria hypogynous or sometimes perigynous. ternatea (Sangu pushpam) Calyx: Sepals 5, green, synsepalous, more Habit: Twining climber or less united in a tube and persistant, valvate Root: Branched tap root system having or imbricate, odd sepal is anterior in position. nodules. Corolla: Petals 5, apopetalous, unequal and Stem: Aerial, weak stem and a twiner papilionaceous, vexillary or descendingly imbricate aestivation, all petals have claw at Leaf: Imparipinnately compound, the base. The outer most petal is large called alternate, stipulate showing reticulate standard petal or vexillum, Lateral 2 petals venation. Leaflets are stipellate. Petiolate are lanceolate and curved. They are called and stipels are pulvinated. wing petals or alae. Anterior two petals are Inflorescence: Solitary and axillary partly fused and are called keel petals or Flower: Bracteate, bracteolate, bracteoles carina which encloses the stamens and pistil. usually large, pedicellate, heterochlamydeous, Androecium: Stamens 10, diadelphous, complete, bisexual, pentamerous, zygomor- usually 9+1 (Clitoria ternatea). The odd stamen phic and hypogynous. is posterior in position. In Aeschynomene Calyx: Sepals 5, synsepalous, green aspera, the stamens are fused to form two showing valvate aestivation. Odd sepal is bundles each containing five stamens (5)+(5). anterior in position. Stamens are monadelphous and dimorphic Corolla: Petals 5, white or blue ie. 5 stamens have longer filaments and apopetalous, irregular papilionaceous other 5 stamens have shorter filaments thus corolla showing descendingly imbricate the stamens are found at two levels and the aestivation. shape of anthers also varies in (Crotalaria Androecium: Stamens 10, diadelphous verrucosa). (5 anthers are long and lanceolate, (9)+1, nine stamens fused to form a bundle and the other 5 anthers are short and and the tenth stamen is free. Anthers are blunt). Anthers are dithecous, basifixed and dithecous, basifixed, introse and dechiscing dehiscing longitudinally. by longitudinal slits.

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XIth_BIO-BOTANY_Ch_5-EM.indd 105 5/17/2020 11:17:54 PM Gynoecium: Monocarpellary, uni- Fruit: Legume locular, with many ovules on mariginal Seed: Non-endospermous, reniform. placentation, ovary superior, style simple Floral Formula: and incurved with feathery stigma. Dt0.Dtn0.'.""."M*7+.E7.C*;+-3.I3

Standard petal Stigma Stamen Style Ovary Calyx Stipe

L.S of flower

Anther Filament

Habit Single stamen Sepal Standard petal

Androecium

Wing petal Calyx

Keel petal Stigma Corolla Style

Ovule Ovary Locule Stipe Gynoecium C.S.of Ovary

Floral formula

Br.,Brl.,%, , K(5),C5,A(9)+1,G1 Floral diagram Figure 5.13: Clitoria ternatea

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XIth_BIO-BOTANY_Ch_5-EM.indd 106 5/17/2020 11:17:55 PM Economic Importance

Economic Useful importance Binomial part Uses Pulses Cajanus cajan (Pigeon Pea) Seeds Sources of protein and starch of our food. Phaseolus vulgaris (French bean) Cicer arietinum (Chick pea / Channa / க�ொண்翈க்கடை) Vigna mungo (black gram / உ쿁ꏍ鏁) Vigna radiata (green gram / பா殿ப்ய쟁) Vigna unguiculata (cow pea / தட்翈ப்ய쟁) Glycine max (soya bean) Macrotyloma uniflorum (Horse gram / க�ொ쿍쿁) Food plants Lablab purpureus (field bean) Tender Vegetable fruits Sesbania grandiflora (agathi) Leaves Greens

Cyamopsis tetragonoloba Tender Vegetable (cluster bean) fruits Oil Plants Arachis hypogea (ground nut) Seeds Oil extracted from the seeds is edible and used for cooking. Pongamia pinnata (pungam) Seeds Pongam oil has medicinal value and is used in the preparation of soap. Timber Dalbergia latifolia (rose wood) Timber Timber is used for making furniture, cabi- Plants Pterocarpus santalinus net articles and as building materials. (red sandalwood) P.marsupium (வேங்க)

Medicinal Crotalaria albida Roots Used as purgative Plants Psoralea corylifolia Seeds Used in leprosy and leucoderma (கார்போக அ쎿殿) Glycyrrhiza glabra Roots Immuno modulater (Licorice root / அ鎿ம鏁ர믍) Mucuna pruriens (ꯂனைக்க쮿) Seeds Neurological remedy Fibre Plants Crotalaria juncea Stem Used for making ropes. (sunhemp / சணப்ப) fibres Sesbania sesban (aegyptiaca) (Bast)

Pith Plant Aeschynomene aspera Stem pith Used for packing, handicraft and fishing floats Dye Plants Indigofera tinctoria (Avuri) Leaves Indigo dye obtained from leaves is used to colour printing and in paints. Clitoria ternatea Flowers Blue dye is obtained and seeds Butea monosperma Flowers Natural dye

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XIth_BIO-BOTANY_Ch_5-EM.indd 107 5/17/2020 11:17:55 PM Economic Useful importance Binomial part Uses Ornamental Butea frondosa Entire Grown as ornamental plants. Plants (Flame of the forest), plant Clitoria ternatea, Lathyrus odoratus (Sweet pea) and Lupinus hirsutus (Lupin)

Diabetes Remedy The seeds of Abrus The aerial parts ofGalega precatorius are used in officinalis (Fabaceae) necklaces and rosaries, contains Metformin but are extremely (dimethyl biguanide). It is poisonous and can be now reputed to be the most fatal if ingested. widely prescribed agent in the treatment of diabetes all over the world. The attractive seeds of INTERNATIONAL Adenanthera pavonina YEAR OF PULSES (Family: Caesalpiniaceae) The Food and Agriculture Organization have been used as units of (FAO) of the United Nations has been weight for the measures of declared 2016 as the year for pulses, gold throughout India. to make people more aware of the nutritional value of pulses.

5.13.2 Family: Solanaceae the largest genus of the family with about (Potato Family / Night shade 1500 species. Plants are worldwide in family) distribution but more abundant in South Systematic Position America. APG system of Bentham and Hooker Habit: Mostly annual herbs, shrubs, small classification system of classification trees (Solanum violaceum) lianas with prickles Kingdom Plantae Kingdom Plantae (Solanum trilobatum) Clade Angiosperms Class Dicotyledonae Root: Branched tap root system. Clade Eudicot Subclass Gamopetalae Stem: Herbaceous or woody; erect or twining, or creeping; sometimes modified into Clade Asterids Series Bicarpellatae tubers (Solanum tuberosum) it is covered with Clade Solanales Order Polemoniales Spines (Solanum tuberosum) Family Solanaceae Family Solanaceae Leaves: Alternate, simple, rarely pinnately compound (Solanum tuberosum and General Characters Lycopersicon esculentum, exstipulate, opposite Distribution: or sub-opposite in upper part, unicostate Family Solanaceae includes about 88 genera reticulate venation. Yellowish verbs present in and about 2650 species, of these Solanum is Solanum tuberosum

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XIth_BIO-BOTANY_Ch_5-EM.indd 108 5/17/2020 11:17:57 PM Inflorescence: Generally axillary or Stem: Stem is hollow, green and terminal cymose (Solanum) or solitary herbaceous with strong odour. flowers (Datura stramonium). Extra axillary Leaf: Simple, alternate, petiolate, entire scorpiod cyme called rhiphidium (Solanum or deeply lobed, glabrous exstipulate americanum) solitary and axillary (Datura showing unicostate reticulate venation. and Nicotiana) umbellate cyme (Withania Inflorescence: Solitary and axillary somnifera). cyme. Flowers: Bracteate or ebracteate, pedicellate, Flower: Flowers are large, greenish white, bisexual, heterochlamydeous, pentamerous bracteate, ebracteolate, pedicellate, complete, actinomorphic or weakly zygomorphic due to heterochlamydeous, pentamerous, regular, oblique position of ovary, hypogynous. actinomorphic, bisexual and hypogynous. Calyx: Sepals 5, Synsepalous, valvate Calyx: Sepals 5, green synsepalous persistent (Solanum americanum), often showing valvate aestivation. Calyx is accrescent. (Physalis) mostly persistent, odd sepal is posterior in Corolla: Petals 5, sympetalous, rotate, position. tubular (Solanum) or bell- shaped (Atropa) or Corolla: petals 5, greenish white, infundibuliform (Petunia) usually alternate sympetalous, plicate (folded like a fan) with sepals; rarely bilipped and zygomorphic showing twisted aestivation, funnel shaped (Schizanthus) usually valvate, sometimes with wide mouth and 10 lobed. convolute (Datura). Androecium: Stamens 5, free from one Androecium: Stamens 5, epipetalous, another, epipetalous, alternipetalous and filaments usually unequal in length, stamens are inserted in the middle of the corolla only 2 in Schizanthus (others 3 are reduced tube. Anthers are basifixed, dithecous, with to staminode), Anthers dithecous, dehisce long filament, introse and longitudinally longitudinally or poricidal. dehiscent. Gynoecium: Ovary bicarpellary, Gynoecium: Bicarpellary, syncarpous syncarpous superior ovary, basically obliquely placed, ovary superior, bilocular but bilocular but tetralocular due to the looks tetralocular due to the formation of false formation of false septum. Carpels are septa, numerous ovules in each locule on axile obliquely placed and ovules on swollen placentation. axile placentation. Style simple long and Fruit: A capsule or berry. (Datura & filiform, stigma two lobed. Petunia, Lycopersicon esculentum, Capsicum) Fruit: Spinescent capsule opening by Seed: Endospermous. four apical valves with persistent calyx. Seed: Endospermous. Botanical description of Datura metel Floral Formula: Habit: Large, erect and stout herb. Dt0.Gdtn0.""".""".M*7+.E*7+.C7.I*4+ Root: Branched tap root system.

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XIth_BIO-BOTANY_Ch_5-EM.indd 109 5/17/2020 11:17:57 PM Leaf Stamen Corolla Stamen Corolla Calyx Calyx

Flower entireHabit

Corolla Stigma

Sepal Anther Style Ovule Swollen Epipetalous placenta stamens Ovary C.S. of Ovary

Corolla cut openCalyx Gynoecium

Valve Spiny Seed outgrowth Spiny Persistent outgrowth calyx Persistent calyx Fruit: Spinescent Fruit - After capsule dehiscence

Floral formula Floral Diagram Br.,Ebrl., , ,K(5),C(5),A5,G(2) Figure 5.14: Datura Metel Economic importance Economic importance of the family solanaceae Economic S.No. Binomial Useful part Uses importance 1. Food plant Solanum tuberosum (potato) Underground Used as vegetables and also used stem tubers for the production of starch. Lycopersicon esculentum Ripened fruits Used as delicious vegetable (tomato) and eaten raw. Solanum melongena Tender fruits Cooked and eaten as (brinjal) vegetable. Capsicum annuum (bell Fruits Used as vegetables and peppers & chilli papers) powdered chilli is the dried C. frutescens (뮿ளகா뿍) pulverized fruit which is used as spice to add pungency or piquancy and flavour to dishes. Physalis peruviana (cape Fruit Used as delicious fruit. gooseberry / ச�ொடக埁 தக்க쾿)

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XIth_BIO-BOTANY_Ch_5-EM.indd 110 5/17/2020 11:17:57 PM Economic importance of the family solanaceae Economic S.No. Binomial Useful part Uses importance 2. Medicinal Atropa belladonna Roots A powerful alkaloid ‘atropine’ plant (deadly nightshade) obtained from root is used in belladonna plasters, tinctures etc. for relieving pain and also for dialating pupils of eyes for eye –testing. Datura stramonium Leaves and roots Stramonium drug obtained (ஊமத்த) from the leaves and roots of this is used to treat asthma and whooping cough. Solanum trilobatum Leaves, flowers Used to treat cough. (鏂鏁வளை) and berries Withania somnifera Roots Used in curing cough and (Ashwagandha / அ믁க்கரா) rheumatism. 3. Tobacco Nicotiana tabaccum Leaves are dried Used in cigarette, beedi, (tobacco / ꯁகை뾿லை) and made into hukkah, pipes as well as tobacco. for chewing and snuffing, alkaloids like nicotine, nornicotine and anabasin are present in tobacco.

4. Ornamental Cestrum diurnum Plant Grown in garden as plants (Day Jasmine) ornamental plants for their Cestrum nocturnum (Night aesthetic nature. Jasmine) Nicotiana alata Do tomatoes come from a tree? Petunia hybrida, Schizanthus pinnatus

Solanum betaceum (Tree tomato)

5.13.3 Family: Liliaceae (Lily Family) Note: Liliaceae of Bentham and Hooker included Allium, Gloriosa, Smilax, Systematic position Asparagus, Scilla, Aloe, Dracaena etc. Bentham and Hooker Now under APG, it includes only Lilium APG Classification Classification and Tulipa. All others are placed under different families. Kingdom Plantae Kingdom Plantae Clade Angiosperms Class Monocotyledons General Characters Clade Monocots Series Coronarieae Distribution: Liliaceae are fairly large family Order Liliales Order Liliales comprising about 15 genera and 550 species. Family Liliaceae Family Liliaceae Members of this family are widely distributed over most part of the world.

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XIth_BIO-BOTANY_Ch_5-EM.indd 111 5/17/2020 11:17:58 PM Habit: Mostly perennial herbs 12, apostamenous, opposite to the tepals, persisting by means of a sympodial rhizome sometimes epitepalous; filaments distinct (Polygonatum), by a bulb (Lilium) corm or connate, anthers dithecous, basifixed or (Colchicum), shrubby or tree like (Yucca and versatile, extrose, or introse, dehiscing usually Dracaena). Woody climbers, climbing with by vertical slit and sometimes by terminal the help of stipular tendrils in Smilax. Trees pores; rarely synstamenous (Ruscus). in (Xanthorrhoea), succulents (Aloe). Gynoecium: Tricarpallary, syncarpous, Root: Adventitious and fibrous, and the odd carpel usually anterior, ovary typically contractile. superior, trilocular, with 2 rows of numerous Stem: Stems usually bulbous, rhizomatous ovules on axile placextation; rarely unilocular in some, aerial, erect (Dracaena) or climbing with parietal placentation, style usually one; (Smilax) in Ruscus the ultimate branches are stigmas 1 or 3; rarely the ovary is inferior modified into phylloclades, In Asparagus (Haemodorum), nectar – secreting septal stem is modified into cladodes and the leaves glands are present in the ovary. are reduced to scales. Fruit: Fruit usually a septicidal or loculicidal capsule or a berry as in Asparagus Leaf: Leaves are radical (Lilium) or cauline and Smilax. (Dracaena), usually alternate, opposite (Gloriosa), sometimes fleshy and hollow, Botanical description of Allium cepa reduced to scales (Ruscus and Asparagus). The (In APG classification, Allium cepa is placed venation is parallel but in species of Smilax it is under the family Amaryllidaceae) reticulate. Leaves are usually exstipulate, but in Habit: Perennial herb with bulb. Smilax, two tendrils arise from the base of the Root: Fibrous adventitious root system leaf, which are considered modified stipules. Stem: Underground bulb Inflorescence: Flowers are usually borne Leaf: A cluster of radical leaves emerges in simple or branched racemes (Asphodelus) from the underground bulb, cylindrical and spikes in Aloe, huge terminal panicle in Yucca, fleshy having sheathy leaf bases with parallel solitary and axillary in Gloriosa, solitary and venation. terminal in Tulipa. Inflorescence: Scapigerous i.e. the Flowers are often showy, Flowers: inflorescence axis (peduncle) arising from pedicellate, bracteate, ebracteolate, the ground bearing a cluster of flowers at except Dianella and Lilium, bisexual, its apex. Pedicels are of equal length, arising actinomorphic, trimerous, hypogynous, from the apex of the peduncle which brings rarely unisexual (Smilax) and are dioecious, all flowers at the same level. rarely tetramerous (Maianthemum), slightly Flower: Small, white, bracteate, zygomorphic (Lilium) and hypogynous. ebracteolate, pedicellate, complete, trimerous, Perianth: Tepals 6 biseriate arranged in actinomorphic and hypogynous. Flowers are two whorls of 3 each, apotepalous or rarely protandrous. syntepalous as in Aloe. Usually petaloid or sometimes sepaloid, odd tepal of the outer whorl Perianth: Tepals 6, white, arranged in two is anterior in position, valvate or imbricate, whorls of three each, syntepalous showing tepals more than six in Paris quadrifolia. valvate aestivation. Androecium: Stamens 6, arranged Androecium: Stamens 6, arranged in 2 whorls of 3 each, rarely stamens are in two whorls of three each, epitepalous, 3 (Ruscus), 4 in Maianthemum, or up to apostamenous /free and opposite to tepals.

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XIth_BIO-BOTANY_Ch_5-EM.indd 112 5/17/2020 11:17:58 PM Anthers dithecous, basifixed, introse, and Fruit: A loculicidal capsule. dehiscing longitudinally. Seed: Endospermous Gynoecium: Tricarpellary and Floral Formula: syncarpous. Ovary superior, trilocular with Br.,Ebrl., , ,P A ,G two ovules in each locule on axile placentation. (3+3) 3+3 (3) Style simple, slender with simple stigma.

Inflorescence Pedicel Bract Flower Peduncle

Cylindrical fleshy leaf Bract Peduncle

Inflorescence

Epitepalous stamen

Filament

Ovary Perianth Bulbose stem Pedicel

Habit Flower entire

Stigma Style Locule Anther Ovule Stigma Ovary Style Ovary Carpel Pedicel L.s of flower Gynoecium C.S. of ovary

Floral formula

Br.,Ebrl., , ,P(3+3) A3+3,G(3)

Floral diagram Figure 5.15: Allium cepa

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S.No Economic Binomial Useful part Uses importance 1 Food plant Allium cepa Bulbs Used as vegetable, stimulative, diuretic, expectorant with bactericidal properties. Allium sativum Bulbs Used as condiment and also good for heart. Asparagus officinalis Fleshy shoots Used as vegetables. 2. Medicinal plant Aloe vera Leaves Gelatinous glycoside called aloin from succulent leaves are used in soothing lotions, piles and inflammations, hemorrhoidal salves and shampoos. Asparagus racemosus Roots Medicinal oil is prepared from the root is used for nervous and rheumatic complaints and also in skin diseases. Colchichum luteum Roots Used in the treatment of gout and rheumatism. Gloriosa superba Tubers Tubers helpful in promoting labour pains in women. 3. Fibre yielding Phormium tenax Fibre Used for cordage, fishing net, plant mattings, twines. 4. Raticides Urginea indica Bulbs Used for killing rats. Insecticides Veratrum album Bulbs Used as insecticide. 5. Polyploidy Colchicum luteum Corm Colchicine (alkaloid) used to induce polyploidy. 6. Ornamental Agapanthus africanus Plant Some of the well known garden plants (African Lily) ornamentals. Gloriosa superba Can you identify this? (Malabar glory lily) a. Name the family. Lilium giganteum b. Write the binomial. c. List the economic uses. Ruscus aculeatus (Butchers Broom) Yucca alcifolia and Y.gloriosa

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XIth_BIO-BOTANY_Ch_5-EM.indd 114 5/17/2020 11:17:59 PM In Yucca the cross-pollination is carried out by special moth, Pronuba yuccasella. Fully opened flowers emit perfumes and are visited by the female moth, especially during nights. This moth collects a lot of pollen grains from one flower and visits another flower. Life history of this moth is intimately associated with the pollination mechanism in Yucca.

State Flower of Tamil Nadu biological and phylogenetic Gloriosa superba species. Taxonomic aids are the tools for the taxonomic study such as keys, flora, revisions, catalogues, botanical gardens Anthers extrose and herbaria. Botanical gardens and versatile. Ascrambling or serve different purposes. They climbing plant. have aesthetic value, offers scope for botanical research, conservation of rare species leaves subopposite, the leaf tip is modified into and propagation of many species. Botanical survey of The flower petals, wavy on tendril. the edges, greenish yellow India explores and documents when bloom, turn flame red biodiversity all over India. at the tips when matures It has 11 regional centres in India. Herbarium preparation The plant contain the alkaloid colchicine. It includes plant collection, is widely used as an documentation of field data, experimental tool in the study of cell preparation of plant specimens, division. mounting and labelling. There are several national and Petals have wavy edges international herbaria. National and are strongly turned Fruit is a fleshy capsule. backwards. herbaria include MH, PCM, CAL etc. Kew herbarium is the The name of Gloriosa superba is composed of two greek words world’s largest one. Gloriosa means full of glory, superba means superb. Classification is the This plant was placed earlier in Liliaceae. basis for cataloguing and retrieving information about Summary the tremendous diversity of flora. It helps us to Taxonomy deals with the identification, know about different varieties, their phylogenetic naming and classification of plants. But systematics relationship and exact position. Some important deals with evolutionary relationship between the systems of classification are fall in to three organisms in addition to taxonomy. Taxonomic types; artificial, natural and phylogenetic. hierarchy was introduced by Carolus Linnaeus. Carolus Linnaeus outlined an artificial system It also includes ranks. Species is the fundamental of classification in “Species Plantarum” in 1753. unit of taxonomic classification. Species concept The first scheme of classification based on overall can be classified into two groups based on the similarities was presented by Antoine Laurent De process of evolution and product of evolution. Jessieu in 1789. A widely followed natural system There are three types of species, morphological, of classification was proposed by George Bentham

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XIth_BIO-BOTANY_Ch_5-EM.indd 115 5/17/2020 11:17:59 PM (1800 - 1884) and Joseph Dalton Hooker. This Evaluation system was not intended to be phylogenetic. One 1. Phylogenetic of the earliest phylogenetic systems of classification classification is was jointly proposed by Adolf Engler and Karl A the most favoured Prantl in a monumental work “Die Naturelichen classification because Pflanzen Familien”. Arthur Cronquist proposed phylogenetic classification of flowering plants it reflects based on a wide range of taxonomic characters a. Comparative Anatomy including anatomical and phytochemical of b. Number of flowers produced phylogenetic importance in his book titled “The c. Comparative cytology evolution and classification of flowering plants.” d. Evolutionary relationships Angiosperm phylogeny group (APG) classification 2. The taxonomy which involves the is the most recent classification of flowering plants similarities and dissimilarities among based on phylogenetic data. APG system is an the immune system of different taxa is evolving and currently accepted system across the termed as world and followed by all the leading taxonomic a. Chemotaxonomy institutions and practising taxonomists. Cladistics is the methodology, used to classify b. Molecular systematics organisms into monophyletic groups, consisting c. Serotaxonomy of all the descents of the common ancestors. The d. Numerical taxonomy outcome of a cladistic analysis is a cladogram and 3. Which of the following is a flowering is constructed to represent the best hypothesis of plant with nodules containing phylogenetic relationships. Chemotaxonomy is filamentous nitrogen fixing micro - the scientific approach of classification of plants on organisms? the basis of their biochemical constituents in them. a. Crotalaria juncea Utilization of the characters of chromosome for the taxonomic inference is known as karyotaxonomy. b. Cycas revoluta The application of serology in solving taxonomic c. Cicer arietinum problems is called serotaxonomy. Molecular d. Casuarina equisetifolia Taxonomy is the branch of phylogeny that 4. Flowers are zygomorphic in analyses hereditary molecular differences, mainly a. Ceropegia b. Thevetia in DNA nuclear and chloroplast sequences, to gain c. Datura d. Solanum information and to establish genetic relationship between the members of different taxonomic 5. What is the role of national gardens in categories. Different molecular markers like conserving biodiversity – discuss allozymes, mitochondrial DNA, microsatellites, 6. Where will you place the plants which RAPDs, AFLPs, single nucleotide polymorphism- contain two cotyledons with cup shaped (SNP), microchips or arrays are used in analysis. thalamus? Molecular Taxonomy unlocks the treasure 7. Give the floral characters of Clitoria chest of information on evolutionary history of ternatea. organisms. It plays a vital role in phytogeography, which ultimately helps in genome mapping and 8. How will you distinguish Solanaceae biodiversity conservation. DNA barcoding is a members from Liliaceae members? taxonomic method that uses a very short genetic sequence from a standard part of a genome. It helps in identification of organisms.

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XIth_BIO-BOTANY_Ch_5-EM.indd 116 5/17/2020 11:17:59 PM ICT Corner

Characteristics of flowers

Look inside the Flower.

Steps

• Scan the QR code or go to google play store • Type online labs and install it. • Select biology and select Character of flower • Click theory to know the basic about Character of flower • Register yourself with mail-id and create password to access online lab simulations

Activity • Select simulation and dissect the different flowers • Record your observations

Step 2

Step 4

Step 1 Step 3

URL:

https://play.google.com/store/apps/details?id=in.edu.olabs.olabs&hl=en

* Pictures are indicative only

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