Bidyut Kr. Jana and Sobhan Kr. Mukherjee. / Journal of Science / Vol 4 / Issue 5 / 2014 / 327-338. e ISSN 2277 - 3290 Print ISSN 2277 - 3282 Journal of Science Botany www.journalofscience.net DIVERSITY OF TESTAL STRUCTURE AMONG SOME TRIBES OF COMPOSITAE *Bidyut Kr. Jana and Sobhan Kr. Mukherjee Department of Botany, University of Kalyani, Kalyani-741235, West Bengal, India, ABSTRACT Seed coat of mature cypselar wall of Compositae is usually termed as testa. It is usually found towords the inner side of pericarp of cypsela. In majority of the taxa, this testal layer exists either attached with the pericarp or secondarily separated from the pericarp. In most cases it is represented by a narrow to wide zone of crusted parenchyma cells or as a dense narrow layer, where cells are not clearly visible, termed as pellicle. Sometimes testal zone is clearly represented by outer and inner zone. Among the tribes of Compositae, the structure of testal zone is very characteristic in Astereae, Arctoteae, Cardueae etc. The structure of testa is less specialized in Inuleae, Heliantheae, Tageteae, Anthemideae, Lactuceae etc. For this study, cypselas of 82 species of the family Compositae have been under taken. Keywords: Testal structure; 82 species; Compositae. INTRODUCTION Grau [1] had recognized the seed coat of wide zone, which can be designated as middle zone of Compositae as testa. He suggested the outer layer of seed testa but actually middle layer of seed coat and inner coat as testa epidermis (TE) and inner part of seed coat as testal zone which is actually inner zone of seed coat. inner testa (T). Reese [2] had coined the term ‘sporoderm’ Outer layer of seed coat i.e. usually represented in the structure of seed coat. Here, the term testa has been by single layer of intact cells or collapsed cells or testal followed after Grau [3] in the structure of seed coat with epidermal cells, which are associated with inner collapsed some modification by others. Here, outer part of seed coat cells of many layers. There is some exception, where seed is recognized as testa epidermis (TE), middle part of seed coat is constitute by outer well organized testa, followed coat designated as testal middle part (TM), whereas inner by middle zone of intact or partially intact cells and inner part clearly differentiated from middle part has been zone of seed coat is constituted by another type of coined as testal inner part (TI). Testa is a term to qualify parenchyma cells or non-cellular pellicle like structure as the seed coat. Actually it is a protective outer coat or an in Helipterum sp. In case of Vernonia bainesii, Mikania integument of a seed of flowering plants. trinervis etc, testal inner zone is well organized i.e. inner According to Cabrera [4] outer layer of seed coat layer of cells have been maintained their structure in is designated as testa, which is usually found in mature mature cypsela. cypselas in cross sectional configuration. Usually in Majority of taxonomist have been included the mature cypsela, testa is represented by a single layer of structure of testa during the description of anatomical dimersified type of cells or it is represented by a narrow features of cypselas, but there are a few papers in or wide zone of collapsed tissue. However in some cases, Compositae, which deals with the structure of testa. testa is associated with inner two narrow or moderately Therefore there is a scope to analyze Corresponding Author:- Bidyut Kr. Jana Email:[email protected] 327 Bidyut Kr. Jana and Sobhan Kr. Mukherjee. / Journal of Science / Vol 4 / Issue 5 / 2014 / 327-338. the characeteristic features of testa in some taxa of primitive one in comparison to advanced taxa, which Compositae. Since testal features have significant value have disorganized testal epidermis i.e. testal epidermal for the betterment and upgradation of Compositae cells lack sclerification and wall thickening. This view systematic. was adapted on the studied of fruit development in Calenduleae and Arctotideae as well as in two species On the basis of testal structure, the studied taxa of of Anthemideae. On the perspective of modern idea, Compositae can be divided into following types: regarding Compositae classification [5-8], it has been Type: 1. Testal layer is made up of crusted layer of indicated that these two tribes have been placed in parenchyma cells, uni-seriately arranged. E.g.-Crepis advanced position. So, present study support the alpina,Crepis aspera, Crepis pyrenaica, Leontodon placement of these two tribes in advanced group instead muelleri etc. of ancient position in earlier system of Compositae Type: 2. Testal layer is made up of thin-walled, classification. horizontally placed, parenchyma cells. Testal cells usually lacks Ca-oxalate crystals, E.g.-Hypochaeria uniflora, Tragopogon porrifolius, but the presence of crystals in testal region has been Sonchus wightianus, Sonchus oleraceous, Leontodon reported in Pulicaria dysenterica of the tribe Inuleae by crispus, Hieracium racemosum etc. Jana, Bar and Mukherjee [9]. In the cypselas ofInula Type: 3. Testal layer is made up of thick-walled, ensifolia, Inula helenium, Pulicaria dysenterica, Telekia horizontally placed, parenchyma cells. E.g.- Aster speciosa, Solidago gigantea, Solidago Canadensis, albanicus, Helianthus debilis etc. Solidago virgaurea, Aster alpinus, Lactuca serriola, Type: 4. Testal layer is made up ‘U’-shape parenchyma Pieris hieraciodes etc. seed coat are attached with cells, uniseriately arranged. pericarp, but in some cypselas (Inula Britannica, E.g.- Cichorium endivia, Aster alpinus, Felicia Leontodon muelleri etc.), seed coats are secondarily heterophylla, Olearia ramulosa, Gazania krebsiana , separated from the pericarp. Secondarily separated seed Leptorhynchos elongates etc. coat from pericarp has been considered by Grau as Type: 5.Testal layer is made up of bi-seriately fairly advanced taxa than the seed coat is attached with arranged, parenchyma cells. E.g. Tragopogon the pericarp. orientalis, Tragopogon pratensis, Vernonia galamensis The structure of mature testal layer may be etc. developed in the following ways. In some taxa Type: 6. Testal layer is made up of palisade (Leontodon muelleri,Crepis palaestina, Crepis parenchyma cells. E.g. Centaurea aspera, Centau dioscoridis, Crepis alpina, Crepis foetida,etc.), entire sabiosa, Centaurea stobe, Arctium lappa , Cirsium seed coat layers disintegrate and form a testa of arvanse , Circium candelabrum, Cirsium heleniodes , collapsed cells only. In some other taxa, seed coat or Montisalea salmantica etc. outer coat or integumental epidermis, remain as such as Type: 7. Testal layer is biseriately arranged and is made previous state and form a cellular layer, which are up of both normal and crusted layer of parenchyma formed in majority of the studied taxa, while in some cells. E.g. Carpesium cernuum other taxa, entire or part of seed coat remain as such as Type: 8. Testal layer is biseriately arranged and is made in younger stage or more or less younger.So, the mature up of both the normal and palisade parenchyma cells. cypselas (In early state), cypselar coat is clearly E.g. Serratula tinctoria differentiated into outer testa of single layer, middle zone of testa and inner zone of testa. Actually the MATERIALS AND METHODS middle and inner zone of seed coat are represented by Cypselas were procured from different foreign inner part of testal epidermal cells. herbaria of the world as gift. The names of studied taxa Testa is highly specialized and thick walled in with their sender address are given in the table-1. The some tribes (Astereae, Cardueae etc.) and less specific studied taxa are arranged in alphabet order of the and less distinct in the tribes like Vernonieae, genera. Senecioneae, Inuleae, Lactuceae etc. For the observation of testal features, cross sections In majority of taxa (Chondrilla juncea, have been taken from the middle part of cypselas with Lactuca pseudoumbrella, Cichorium intybus, the help of sharp razor blade to observe the different Urospermum dalechampii, Lapsana communis, anatomical regions, mainly the testal structure in mature Tragopogon porrifolius, Layia platyglossa, Madia cypselas. elegans etc.), testal epidermal cells are arranged in tangential fashion. There are some taxa (Elephantopus RESULTS AND DISCUSSION carolinianus,Pieris hieraciodes, Centaurea aspera, On the basis of the nature of tissue organijation Centaurea sabiosa, Centaurea stoebe etc.), which have and layers of arrangements of cells, different types of radially oriented testal epidermal cells. Such type of testal structures have been noted, which are given in the taxa may be more advanced in comparison to table-2. tangentially oriented testal arrangement of cells. According to Reese (1989), taxa having well Therefore, it is essential that testal structure organized testa epidermis has been considered as has significant role for characterization of taxa along 328 Bidyut Kr. Jana and Sobhan Kr. Mukherjee. / Journal of Science / Vol 4 / Issue 5 / 2014 / 327-338. with pericarpic features of Compositae as advanced in by Briquet, Schuttz-Bipontinus and some others [10- earlier time, on the basis of cypselar anatomical studies 11]. Table 1. Name of taxa and Sender address Sl.no Name of taxa Sender address Acanthospermum hispidum DC. Instituto De Investigacao Cientifica De Angola, Herbarium 1 (Millerieae) (LUAI). Col: A. Menezes, Dated 28. 6. 1972. No-4223 Anthemis maritima L. Botanischer Garten der Universitat Zurich. XXOBRISS- 2 (Anthemideae) 20053261 Arctium lappa L. Humboldt- Universitat zu Berlin. Institut fur Biologie, Spezielle 3 (Cardueae) Botanik u. Arboretum, Berlin, Germany. Collection Number- 704. Artemisia vulgaris L. Botanic Garden Of The University, Jyeangontie 2, SF- 00550 4 (Anthemideae) Helsinki, Finland. Aster albanicus Degen. Botanic Garden of the University of Copenhagen, Danmark. 5 (Astereae) 211S2000-0862*A Humboldt- Universitat Zu Berlin, Institut fur biologie, Spezielle 6 Aster alpinus L.(Astereae) Botanik u. Arboretum, Spathstra βe 80/81, D-12437, Berlin, Germany. Bahia absinthifolia Benth. 7 Swedish Museum of Natural History, Stockholm, Sweden. (Bahieae) Berkheya purpurea (DC.) Mast.