Seed Coat Structure in Some Species of Atylosia (Phaseoleae - Cajaninae)

Scanning Microscopy Volume 1 Number 3 Article 60 5-27-1987 Seed Coat Structure in Some Species of Atylosia (Phaseoleae - Cajaninae) B. S. Trivedi Lucknow University Mohini Gupta Lucknow University Follow this and additional works at: https://digitalcommons.usu.edu/microscopy Part of the Life Sciences Commons Recommended Citation Trivedi, B. S. and Gupta, Mohini (1987) "Seed Coat Structure in Some Species of Atylosia (Phaseoleae - Cajaninae)," Scanning Microscopy: Vol. 1 : No. 3 , Article 60. Available at: https://digitalcommons.usu.edu/microscopy/vol1/iss3/60 This Article is brought to you for free and open access by the Western Dairy Center at DigitalCommons@USU. It has been accepted for inclusion in Scanning Microscopy by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. Scanning Microscopy, Vol. 1, No. 3, 1987 (Pages 1465-1474) 0891-7035/87$3.00+.00 Scanning Microscopy International, Chicago (AMF O'Hare), IL 60666 USA SEED COA T STRUCTURE IN SOME SPECIES OF ATYLOSI A (Phaseoleae - Cajaninae ) B.S. Triv edi* and Mohini Gupta Department of Botany, Lucknow University, Lucknow-226007 India (Received for publication December 08, 1986, and in revised form May 27, 1987) Abstract Introdu ction Scanning e lectron microscopy and light micros .f:.ty losia, a papilionoid legume genus of the sub copy were used to examine seed characters of ten tribe Cajaninae, Benth. of the tribe Phaseo!eae is species of the legume genus Aty!osia. Seeds of all represented by about 35 species distributed from the species are arillate with a ce ntral hi!ar groove, Asia to Australia. Plants may be erect, trailing or a cha racter useful fo r specific delineation of the twining herbs or shrubs with large arillate seeds . genus. The testa of A.aJbicans, A.cajanifo !ia, !::__. Some of its species are economica lly important e .g . Janceolata, A.scarabaeoides and A.volubilis is mu!ti _f:..goensis Daiz (=A.barbata Baker), which is said to reticulate. It is rugulate in the rest of the species. be benef icial in rheumatism and fever (Chopra, 1933) Differences in the size and a rr angement of rugae whi le A. oensis and A.scarabaeoides a re used as can be utilized to se par a t e them from one another. green manure Burkill, 1935). Aty losia is conside red The sha pe of the hiJum and micropyle is distinctive 07e of the wild re lat ives of the pigeon pea. Therefore, for some species. It was observed that the length many of its species are used in Cajanus breeding of palisade ce lls and hour g lass ce lls a re not cor to acquire many of the desired features in cu lti vated related with seed size . The tra c heid bar is present pigeon pea such as higher pod index, disease and and is of the co mmon fabaceous type; tracheoids insect resistance, and early flowering. Biosystematic s:-iow variations in pitting and vesturing . Based on studies, encompassing morpho-cytoJogica l and e lectro the character of the ariJ, spermoderm, tracheoids phoretic analyses of Cajanus caJan, seven species a nd pits, a key has been designed to identify species of Atylosia, and one of Rhynchosia, revealed that of Atylosia. It is hoped that this study will be helpful A.ca janifolia is closest to Cajanus cajan followed taxonomically. by A.lineata, A.scarabaeoides, A.sericea, A.albicans, A.volubi lis and A.platycarpa (Pundir and Singh, 1985). Further, Pundir and Singh, 1985 have suggested that the taxonomic status of Cajanus and Aty losia may be retained; based on the closeness as well as following rul es of nomenclature - species like A. cajanifo lia, A.lin eata, A.sericea, A.sca rab aeoides and A.albicans shou ld be placed under the genus Cajanus. !::__.pl atycarpa and !::__.volubili s are quite distant from the pigeon pea, hence these two species should be retained under the genus Atylosia . The spermoderm of some members of this sub tribe (Cajanus cajan, Dunbaria rotundifolia, Eriosema floribundum, Rhynchosia minima and Flemingia f loribundum) has been studied by Lersten ( l 981), who has surveyed 30 tribes of the Papilionoideae and repo rted levigate, ruguJate, rugu lat e-p itt ed and papi11ose pattern in these spec ies . Further, Lersten ( 1982) has reported nonve stur ed to vestured pits in KEY WORDS: AtyJosia, Papi!ionaceae (Faba ceae ), the tracheoids of the tra c heid bar of these species. ariJ, spermoderm, hilum, tra c heid bar, tracheoids. Since no ear lier report on A ty Josia is available, in the pr esent investigation ten species of this genus were tak en into co nsideration. All the species have been com pared for spermoderm, hilum, tracheid *Address for correspondence: bar and pits which may help in their identification B. S. Trivedi at the specific leve l. Department of Botany, Lucknow University, Lucknow-226007 India Materials and Methods Phone No.: 74794 Seeds were obtained from th e Genetic Resources 1465 B.S. Trivedi and Mohini Gupta Unit, ICRIS AT, Patancheru (A.P.). A minimum of is not as prominent as in othe r species . Clumping ten seeds per spec ie s were examined by scanning of some rugae is found at places in ~ .ca janifolia e lectro n microscope and light microscope. Seeds (Fig.8). were kept whole or sectioned longitudinally or trans In A.goensis (Fig. I J), A.mollis (Fig. J 2) and~ versely through the hilum and were examined under platycarpa (F ig.13) ruga e a re co mpa ct, irregularly the light microscope to select good sections. To arranged and separated by uniform furrows. Among study the shape of the hilum the aril was removed these species minor differences have been observed with a fine blade. Seeds were mounted on brass in the size and arrangement of rugae. Rugae of~ stubs with double stick ca rp et tape and coated with goensis (Fig.I J) are long and appearing to be arranged gold-palladium in a sputter coate r. Seed surfaces in rows; in A.molli s rugae a re small and thi ck (Fig.12) were exam ined at mid-seed and near the hilum. To while in A.platy ca rp a rugae a re long and thin, maintain uniformity, portion immediately adjacent giving the appearance of a multi -reti cu late pattern. to the hilum was considered for spermode rm studies . In A.lineata and A.sericea rugae are of different Seeds were studied in a JEOL-JSM-35C SEM at an sizes . Some rugae are short, irregular in shape and accelerating voltage of 20 kV and recorded on a rrangement while others are longer forming clumps 120 mm ASA. The de sc riptions of the shape of at severa l places. Rugae of ~.I ineata are small, seeds and hilum are based on the terminology used thick and slightly beaded (Fig. 14T7"ncomparison to by Radford et al. ( 1974), the m ic ropy le area was those of A.sericea (F ig.15) in which they are long, fixed as the apical point of reference. The testa thin a nd sub-striate. topography terminology used her e follows that of Critical examination of the testa in transection Lersten (1981). in a ll the species has revealed differences in the sizes of the cells of the outermost layer, i.e., palisade Results cells (Table 3). These cells are longest near the hilum, thick walled and elongated (P. Fig. I 6). Below The size and shape of seeds vary a great deal the palisade lay e r is a laye r of hour glass ce lls (H) (Table I). The seed coats of all the species appear with prominent intercellular spaces. This layer has smooth, shining, choco late brown to black or mottled longer cells near the hilum, becoming shorter towards with light brown patches under low magnifications the mid-seed area (Fig.16). Below the sclereid lay e r, of light microscope. Seeds are ovate in A.lineata, a poorly defined zone of partially or complete ly A.mollis and ~.sericea, ovate to oblong in A.albicans, c rushed ce lls-remn an t layer is visible, which may A.cajanifolia and A.scarabaeoides, ovate to reniform co nsist of remnants of en dosperm ce lls (Fig. l 6). in A.volubilis, ovate to hem ispheri ca l in A.Janceolata, The Tracheid Bar and Tra c heo ids hemispherical in A.platycarpa and hemispheri cal to The tra c he id bar (TB) when observed in tran orbicular in _!\.goensis. The aril is present in all section is present below the hilar groove (HG, Fig.16) the species and is bilobed, horny an d variabl e in and at the upper region is attached to the counte r co lour from dull cream to grey (Table 2). palisade layer (CP, Fig.17). It is embedded in a Differences have a lso been observed in the mass of spongy paren c hyma and is gene rally e llipti c al amount of the area of hilum cove red over by the aril. in shape but va ries in size and shape from narrow Ari! covers almost the entire hilum in A.mollis to broad (Table 3). It s length is not cor related with (Fig. 1) or lea ves behind the cent ra l region as in the the size (length and breadth) of the re spec ti ve seed. rest of the species (Fig.2). In ~.goensis and A.vo lub ilis Tracheoids (small tr ache ids) are oriented ve rti ca lly; (Fig.3) aril is rim -like due to which the centra l these merge with the ovular bundle opposite the furrow of the hilum is c lear ly visible.

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