SEM (SCANNING ELECTRON MICROSCOPY) STUDIES ON SEEDS OF TWO SPECIES OF DIANTHUS (CARYOPHYLLACEAE) SUSHMA SHARMA

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1 J. Indian bot. Soc. ISSN , e-issn: Vol. 95 (3 & 4) 2016: SEM (SCANNING ELECTRON MICROSCOPY) STUDIES ON SEEDS OF TWO SPECIES OF DIANTHUS (CARYOPHYLLACEAE) SUSHMA SHARMA Botany Department of C.C.S. University, Meerut, India Sushma_sharma130@yahoo.co.in Date of online publication- 31 th December 2016 Seed morphology of two species of Dianthus (D. barbatus and D. latifolius) has been studied using the light microscopy and scanning electron microscopy (SEM). Both the species differ in colour, size, shape, seed coat, number of suture point, suture outline, position of hilum, and tubercule shape etc. In two species of Dianthus seed coat are two layered with medium or fine granulation. concavo-convex surface, and embryo is straight. Both species showed little variation in dorsal and ventral side of the seed coat. The suture outline of D. barbatus was serrate sinuous. It was found sharply digitate sinous in D. latifolius. The shape of the seed tubercule prominently obtuse in D. barbatus and finely obtuse in D. latifolius. Keywords : Seeds, LM (Light Micrscopy), stereiomicroscope, SEM (Scanning Electron Microscopy), Seed type, Granulation, Suture Point, Seed tubercle. The Plants of Dianthus belonging to family Caryophyllaceae are ornamental, for taking up any breeding exercise to add value for the flower which is a cash crop and of commercial use Its reproduction biology needs to be understood. The Caryophyllaceae are large dicotyledonous family which has been divided into three sub -families viz Paronychioideae, Alsinoideae and Caryophylloideae and 11 tribes (Bittrich 1993). It includes 86 genera and 2630 species (Mabberley 2008). Some characteristic features of the seed morphology, hilar character, number and lining of the suture, seed coat pattern, seed surface etc. have been studied. Some significant investigations carried out on seed morphology include Davis (1967:88) on Saponaria kotschyi (endemic species) and Baytop 1992 on Saponaria officinalis. Seed characteristic have been used as useful tools at generic and species level as also in making systematics. Seed morphology of Silene sp. was studied by Yildiz (1998). Yildiz (2002), demonstrated the utility of seed characters for specific delimitations in some eleven genera of Caryophyllaceae. The seed morphology of Gypsophilla osmangaziensis was studied by Ataslar and Ocak The seeds of the genus Silene were studied and this data was utilized for specific delimitation Yildiz, 2006, Perveen, 2009: Fawazi, The seed morphologcaly studies provides additional information in solving various taxonomic and evolutionary problem (Akbari and Azizian, 2006, Abid and Ali, 2010, Raj Bhandary and Shrastha 2010, Ackin and Binzet 2011). The present study provides seed morphological data of two species of Dianthus, with the aim to outline the differences between the two very closely related species of the same genus so that it may be utilized towards identification and breeding experiments for commercial value addition. Material and methods: During the course of present study the following data was recorded. 1. Number of seeds per capsule : To find out the number of seeds per capsules, the ripe fruits were kept singly in paper bags and allowed to dehisce, after dehiscence the seeds were counted carefully. 2. Light microscopy.: The seeds were examined under light microscopy for determining the shape and size. 3. Scanning Electron Microscopy : For SEM, the dry seeds were coated with gold for six minutes in a sputtering chambers and mounted on metallic stubs using double adhesive tape. The terminology used here Received on May 03, Accepted on May 30, 2016

2 Sem (Scanning Electron Microscopy) Studies on Seeds 289 Observations : S. No. Name of the species Average weight of the seed (in mg) 1. Dianthus barbatus 0.6mg 2. Dianthus latifolius 0.52mg Numbers of seeds per capsule 19±7 21±4 Colour of the seeds Pale yellow,black or brown some seeds are yellow to brown Black in colour Table-1: Seed Morphology of Two species of Dianthus Size of the seeds (in mm) Shape of the seeds Hilum Seed surface Seed Granuulation Dorsal side of seed coat Ventral side of the seed coat 3.4±0.18 Elongated spindal to oval shape On ridge sub central Flate concavo convex Surface Medium Narrow elongated cells Margin denatate surface covereded with plate Short reticulate cells on ventral side covered with plate, serrate, plate sur-face 3.55±0.15 Oval in shape On ridge concave convex Surface Fine More flate Polygonal cells provide small granules Polygonal area have furrow and ridge cells Smaller cells on ventral side as compare to dorsal side Suture out line Serrate sinuous Sharply digitate sinuous Num ber of suture point Seeds tuber cell shape Prom inently obtuse Finely obtuse

3 SUSHMA SHARMA is in accordance with (Lawrenece 1970, Borgreen, 1981 and Stearin, 1983) with some modification: The following characters were recorded such as size, colour, shape, surface 290 (testa), surface plate and position of hilum etc. Results and Discussion

4 Sem (Scanning Electron Microscopy) Studies on Seeds 291 The seeds bear numerous morphological characters which can be used for taxonomic purposes. The ornamentation feature of the seed surface vary in different species. In Caryophyllaceae the seeds are reniform but in Dianthus they are cylindrical. In both the species the capsule shows seeds attached either in free central or basal manner. The seed morphological data is significant which can be correlated with taxonomic delimitation of family Caryophyllaceae. Some important characters such as seed surface, tubercle shape, suture line, hylarzone, number of seeds per capsule, size and shape of the seeds were studied in both the species Table Generally the hilum of the caryophyllaceae members is al (Except. Dianthus ). In Dianthus the hilum is sub-central,rough surface or tuberculate. Generally the embryo of Caryophyllaceae is curved but in Dianthus it is straight, possessing a short radicle, and large flattended cotyledons. In Dianthus barbatus, the fruit is capsule opening with star shaped structure containing many small seeds developed form a superior ovary. The number of seeds per capsule were recorded as 19±7.The colour of the seeds is pale yellow to brown, rust brown or black. The shape varied spindle to oval and size measured froms 3.4±0.18 mm. The seed surface is and flate concavo-convex. Similar observations were observed by Yildiz (2002) in velezia rigidic. He described that the seed surface was flat concavoconvex. It was observed that the embryo of D. barbatus was straight possessing a short radicle and hypocotyl. Similar observations were observed in six species of Dianthus (D. caryophyllous, D. anatolicus, D. cremelitarum, D. celocephalus and D. crintus) by Yildiz (2006). The cotyledons are two layered, hilum on ridge sub central was observed in D. barbatus. Similar observations were noted in six species of Silene (S. longisepala, S. nana, S. tenuis, S. vulgaris, S. marina, S. media) by Karnwal et.al (2012). ( Table ) Scanning electron microscopic studied showed the dorsal surface of the seeds show narrow elongated cells and covered with plate. The dorsal surface of the seed showed dentate pattern. Similar observations was reported by Karnwal et.al (2012) in Gypsophila alsinoids and lepprodiclis holostoides. The ventral surface of the seeds showed reticulate pattern coverded with plate, the plate surface are. The ventral surface showed serrate pattern. Similar observation was observed in Gypsophila bellidifolia by Karnwal et.al (2012). The number of suture points are 9-12 present in D.barbatus. The shape of the seed tuburcule are prominently obtuse. Similar observations were reported in silene caryophylar by Yildiz (2002). Plate Generally the seed back are flat in both the species. Similar results were observed in Velezia rigidic by Yildiz (2002). The Seed granulation was medium in D. barbatus while fine in D. latifolius. Seed coat are two layered is both the species of Dianthus. The seeds of D. latifolius enclosed in a capsule. The average number of seeds per capsule were recorded 21±4. The colour of the seeds are black, small in size with oval shape. The size of the seeds was 3.55±0.15 mm. The dorsal surface of the seed are concavo-convex. Scanning electron microscopic studies showed different characters. The cells of the dorsal side are more flate polygonal.the polygonal area have furrow and ridge cells. The size of the dorsal side cells are smaller than the ventral side of the cells The hilum present on the ridge. The shape of the seed tubercle was finely obtuse. Simalar observations was observed in D.crinitus variety crircintus by Kamal Yildiz (2002). The number of suture point are 6-10 present in D. latifolius. (Table-1, Plate-1) The present study showed both the species of Dianthus can be differentiated on the basis of external morphology and SEM studies.the

5 SUSHMA SHARMA seeds are different in colour, shape, number of.seeds per capsule, suture point, dorsal and ventral side cells of the seed coat, position of the hilum and shape of the tubercle, the utility of seeds characters will be for genetic and specific delimitations. Similar observations were reported by different researchers in Silene (129), Dianthus (70 sp.), Arenaria (47 sp.), Gypsophilla (51 sp.) Yildiz (2002) studied the seed morphology of different genera of earyophyllacea (Cerastium, Dianthus, Moechia, Stellaria, Velezia etc.), he demonstrated that the utility of seed characters for generic and specific delimitations. Some scientists (Akbari and Azizian 2006, Abid and Ali 2010, Raj Bhandary and Shrastha 2010, Ackin and Binzet, 2011 ) support the seed morphology study. On the basis of observation of present study it is concluded that studied of the seed morphology of the two species of Dianthus provides additional information in solving the taxonomic and evolutionary problems, besides providing identification cues for commercial value addition to these ornamental species. The author is thankful Dr. Sushma Kothari for guidence and to Prof. Y. Vimala, HOD, Botany Department of Ch. Charan Singh University for the help during the present investigation. REFERENCES Abid R and Ali (2010) Cypsela Morphology and its taxonomic significance for the tribesenecioneae (Asteraceae) from Pakistan. Pak. J. Bot (Special issue) Ackin O E and Binzet R 2011 Micromorphological studied of some Onsoma L (Boraginaceae) species from Turkey. Pak. J. Bot 43(2) Akbari R S and Azizian D 2006 seed morphology and seed coat sculpturing of Epilobium L. Species (Onagraceae Juss) from Iran. Turk J. Bot Almeida M R 2009 Flora of Maharashtra volume V-A. Blatter Herbarium, Mumbai. 292 Ataslar E and Ocak A 2005 Gypsophilla Osmangaziensis (Caryophyllaceae) a new species from central Anatolia, Turkey, Ann. Bot. Fennici Baytop A 1992 Traky Ve Turkiye Florasma elave Kaytlar Dogia. T.J. Bot Cribb P and Govaerts R (2005) Just how many orchids are there? In: Raynal-Roques, A., Roguenant, A. & Prat, D. (Eds.) Proceedings of the 18th world orchid conference. NaturaliaPublications, Turriers, pp Wood, H.P. (2006) The dendrobiums. Gantner, Liechtenstein, pp Dressler R L 1993 Phylogeny and classification of the Orchid family. Dioscorides Press. Portland. Oregon. Fawzi N M, Fawzy AM and Mohamed AA Seed morphological studied on some species of silence L. (Caryophyllaceae) Int. J. Bot. 6(3) Hamazoglue E, Koc M and Aksay A 2015 Dianthus aticii, a new species from Turkey (Caryophyllaceae), Phyto keys Karnwal D, Abid R and Qaiser M 2012, The seed atlas of Pakistan-VI, Caryophyllaceae Pak.J. Bot 44(1) Kubitzki K, Rohwer J G,Volker B 1993 The families and Genera of Vascular plants. Vol. (2). Springer Verleg, Berlin. Lakshminarsimhan M, Sharma B D, Karthikeyan S and Singh N P 1996 Flora of Maharashtra State. Botanical survey of India, Calcutta. Lokho Adani 2013 Diversity of Dendrobium Sw. Its distributional patterns and present status in the northeast India. International Journal of Scientific and Research Publications, volume 3 (5). Mabberley D J The plant book cambridge university press, Cambridge.