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12/28/2018 1 Why Botany? Today's Topics What Is a Plant?

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12/28/2018 1 Why Botany? Today's Topics What Is a Plant? 12/28/2018 Why Botany? õ Botany = study of plants! õ Background for many principles you will be Botany for learning õ Plant ID Gardeners õ Pruning Heather Stoven õ Propagation õ Plant growth and processes õ It is fun to learn! Today’s Topics What is a plant? õ Survey of plants and relevant non-plants õ In the kingdom õ Anatomy of plants Plantae õ Leaves õ Generally.. õ Stems õ Make their own food Volvox õ Flowers õ Chlorophyll a & b õ Vascular system õ Multicellular õ Photosynthesis, respiration and õ Cell walls made of transpiration cellulose õ Limited motility õ Plant hormones Indian pipe Variation in plants Kingdom Classification Photos: Linda McMahan 1 12/28/2018 A tour of the plant kingdom… Algae Separated into monocots and eudicots • Some types of algae (green Not Shown: Photo: Linda Fungi, algae) are McMahan certain classified as plants Cyanobacteria algae others are not (not a plant) Not Plants but important… Slime Molds õ Slime molds are primitive single cell organisms that travel together as a crowd OSU disease clinic õ Occur on moist soil, lawns, stumps and mulch õ Not deleterious to plants Photos: Linda McMahan Fungi Fungi õ Often see the õ Form spores fruiting body õ Fungi are above ground decomposers and õ Hyphae are strands some are ucanr.edu of fungus pathogens õ Most of fungal organism is õ Many have positive underground and associations with unseen plants cals.ncsu.edu 2 12/28/2018 Symbiosis Lichens õ relationships õ Can live in extreme between species environments as epiphytes – arctic, õ Mycorrhizae – deserts, rocky areas between plants õ Long lived, slow and fungus growing, many 1mm/yr õ Lichen – between õ Vulnerable to fungi and algae environmental disturbance Back to Plants… Mosses Liverwort õ Reproduce via õ A lot like mosses spores except more õ Lack an extensive differentiated vascular system leaves or lobes Horsetail Ferns õ Ancient plants – õ Reproduce via relatives were thick as spores forests and tall as trees õ Have a vascular õ Hollow stems and transport system jointed õ Can be tree size õ Produce spores õ Have vascular system õ Most need moist sites õ Stiff due to retention of silica 3 12/28/2018 Male cones Conifers Female cones Flowering Plants õ Classified as gymnosperms –- õ Angiosperms – seeds “naked seed” enclosed õ Produce cones õ Principle group of õ Foliage is needles or plants on earth scales õ Identifying structures õ In junipers, “berries” are õ Leaves female cones õ Stems õ Most are evergreen, but some are deciduous õ Flowers õ Non-deciduous also õ fruits shed needles each year Plant identification Eudicots vs. Monocots • Monocot vs. õ Monocots eudicot õ Flower parts are in 3’s, • Leaf arrangement leaf veination parallel, • # petals one cotyledon • Flower type õ Eudicots • Flower parts õ Flowering parts typically • Fruit type multiples of 2, 4 or 5 • Other õ Two cotyledons • Hairs • thorns õ Vein patterns palmate or pinnate • sap Monocots and Eudicots Monocot or Eudicot õ Plant families will be either monocots or õ Flowering parts? eudicots õ Monocot family examples: õ Veination? õ Liliaceae õ Iridaceae õ Poaceae õ Eudicot family examples: õ Asteraceae õ Brassicaceae õ Roseaceae 4 12/28/2018 Monocot or Eudicot Leaf structure õ Flowering parts? õ Arrangement õ Opposite/alternate/ õ Veination? whorled Note: Leaves have an opposite arrangement Leaf blade Leaf Parts Leaf structure petiole õ Adaptations to the environment õ Hairs Node = place õ Wax of attachment õ Trichomes to the stem Petiole trichomes Leaf structure Leaf structure õ Shape õ shape õ Chordate õ Linear õ ovate 5 12/28/2018 Leaf structure Leaf structure õ Leaf margins õ Simple õ Lobed õ Dentate õ Entire Leaf structure Leaf structure õ Simple õ Compound palmate Leaf structure Leaf Structure • Compound leaves bipinnate pinnate palmate 6 12/28/2018 Exercise – Look at the Parts of a Twig Stems õ Provide structure Terminal bud õ Parts of the stem: Auxillary node nodes and buds internodes Leaf scars Bud scale scars Slide: Linda McMahan Bark Roots õ Protects the tree’s õ Anchor plants vital growing areas õ Absorb water and mineral nutrients õ Can be beautiful! õ Often stores food õ Can be reproductive õ Adventitious roots, etc. õ Types of roots õ Tap – anchorage, storage õ Fibrous – shallow, cover large area Tap root fibrous root Roots Flowers õ Many “roots” are õ Contain reproductive specialized stems structures õ Tubers õ Bulbs õ Corms õ Rhizomes StudyPage.in 7 12/28/2018 Flowers Flowers õ Petal number õ Regular (radial) vs. irregular (bilateral) õ Flower parts õ inflorescences Flowers Flowers õ Perfect õ Imperfect flowers õ Has male and õ Monoecious female parts õ Male (staminate) and female Pumpkin flowers on same plant - õ Imperfect flowers (pistillate) monoecious õ Lacking parts on same plant õ Called staminate õ Dioecious or pistillate flowers õ Male and female flowers not on same plant Staminate (L), Pistillate (R) Skimmia - dioecious Flowers – an example Flowers – an example õ Flowers can be complete õ (has sepals, petals, Corn stamens and pistils) or õ An example of incomplete (missing one of above) incomplete flowers õ Hydrangeas õ Plants are monecious õ An example of õ Imperfect - Staminate incomplete flowers õ Contains sterile and fertile and pistillate flowers flowers õ “petals” are really sepals (calyx) õ Cluster of flowers called corymb (top photo) 8 12/28/2018 Exercise – Find the Parts of a Flower Flowers Flower parts õ Imperfect flowers are always incomplete but…. õ Perfect flowers are not always complete but… õ Complete flowers are always perfect. Are your examples complete From wikipedia.org or incomplete? Perfect or imperfect? Monocot or Dicot? Pollination and fertilization Pollination - an Example õ Methods – õ Hazelnuts insects/animals, õ Pollination occurs wind, rain, human in Jan-Feb õ Pollination vs. õ Fertilization takes fertilization place 4-5 mo. later õ Incompatibility õ Hazelnuts are not self-compatible – õ Timing and need pollinizers genetics õ Wind pollinated www.ag.arizona.edu Fruits and berries Fruits õ Seeds are found in õ Types of fruits fruits õ Simple – one ovary õ Fruits provide õ True berry protection and õ pomes sometimes incentives õ Aggregate – many for animal seed ovaries õ Blackberries, strawberries dispensers õ Multiple- fusion of many õ Seed dispersal is very flowers important for the õ Pineapples plant! õ Fruits can be dry or fleshy 9 12/28/2018 Physiology Leaf structure õ Leaves õ Cellular structure and õ Stems physiology õ Roots õ Epidermis õ Adaptations – hairs, õ Photosynthesis waxy cuticle Wikipedia.org õ Transpiration õ Mesophyll õ Respiration õ Most photosynthesis takes place here õ Plant hormones Vascular Systems Stems õ Xylem – water õ Cross section conducting tissue õ Phloem – photosynthate transport õ Cambium – divides to produce xylem and phloem in eudicots Image:Wikispaces.com Vascular structure also important Only eudicots produce for pest management and woody tissue, why? propagation Exercise: look for vascular bundles Stems: wood Stems õ Xylem – water conducting tissue õ Phloem – photosynthate transport õ Cambium – divides to produce xylem and phloem Boundless.com http://www.generalhorticult ure.tamu.edu 10 12/28/2018 Root Structure Epidermis Cortex Roots – Nutrient movement Root Phloem hairs- high Organic matter and many clays have surface area Root high CEC and hold nutrients well meristem- senses gravity Vascular Root cap cambium Xylem CO2 from roots forms H2CO3 dissolves into H H CO3, which draws positive ions from Ca, K, etc. into root. Photosynthesis photosynthesis õ Key to our life on õ Plants are autotrophs!!!!! earth! õ Carbon dioxide from õ Plants make their atmosphere + water from own food soil + energy from sun = food for plant + oxygen õ Only plants do this õ Occurs in chloroplasts, where pigment chlorophyll captures the sun’s energy What is Respiration? Photosynthesis õ A process that all living things go Factors affecting rate through of photosynthesis õ The process occurs during both day õ Water availability and night õ Temperature õ Light õ It is a “breaking down process” õ Plants able to use ≈ 40% of sunlight õ Plants are green because they reflect green wavelengths! õ Blue light = vegetative (fluorescent lights for seedlings) õ Red & blue = flowering 11 12/28/2018 The Process... A Comparison õ Photosynthesis õ Respiration õ Food made during õproduces food õuses food photosynthesis õreleases energy (photosynthates) is broken õstores energy õproduces water down to õuses water generate energy õproduces õuses carbon õ This energy is used for plant carbon dioxide growth dioxide and development õuses oxygen õreleases oxygen õ For growth to occur õoccurs in dark photosynthesis must be õoccurs in sunlight and light greater than respiration What is Transpiration? The Process... õ Water loss (in vapor form) from õ Water is taken up by roots, moved a plant through the plant and then lost as õ Transpiration rate is controlled by vapor through stomata on the stomatal aperture, which is leaves influenced by: õ Helps cool plants õ relative humidity õ Helps move minerals through plants õ temperature õ Light õ 95% of water lost through stomates õ Open when guard cells are turgid, closed when flaccid Light energy Above ground = Photosynthesis, To consider… respiration Transpiration õ Stomates need to be open for C02 photosynthesis and releasing heat O2 Water vapor õ Transpiration is related to the environment õ Plants can be stressed and damaged especially: õ Hot, windy õ If ground is frozen (winter desiccation) õ Plants can adapt – smaller leaves, Below
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