Browsing by Author "Manjula, C."

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    Characterization of Annur and Bedakam Ecotypes of Coconut from Kerala State, India, Using Microsatellite Markers
    (2014-02) Rajesh, M.K.; Samsudeen, K.; Rejusha, P.; Manjula, C.; Shafeeq Rahman; Anitha Karun
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    Characterization of Kuttiyadi ecotype of coconut (Cocos nucifera L.) using morphological and microsatellite markers
    (2014-12) Manjula, C.; Samsudeen, K.; Shafeeq Rahman; Rajesh, M.K.
    West Coast Tall (WCT) is the most popular coconut cultivar grown by the farmers in Kerala, which occupies over 95 per cent of the area under coconut. The long history of coconut cultivation throughout Kerala state has resulted in the development of many ecotypes of WCT. The present work compares the similarity/diversity of the morphological and molecular characteristics of the Kuttiyadi ecotype growing in the hilly, midland region of Kozhikode District, Kerala with those of the WCT cultivar of the coastal region of Kasaragod District, Kerala, using vegetative, reproductive and fruit component characters and microsatellite markers. Geographically, these two locations show a wide range of variation for soil and climactic factors. The vegetative, reproductive and fruit component characteristics and microsatellite markers showed wide variations between selected WCT palms from Kasaragod and Kuttiyadi. The similarity index based on Dice’s coefficient, obtained after pair-wise comparison of Kuttiyadi and WCT samples with 15 SSR markers, revealed that the percentage similarity varied from the coefficient range 0.20 to 0.97 between the WCT and Kuttiyadi palms. UPGMA clustering clearly distinguished the two populations with WCT and Kuttiyadi forming separate clusters. STRUCTURE analysis was also carried out, which also showed that the two populations studied were distinct
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    Germination, growth and dry matter partitioning in coconut
    (2007-02) Manjula, C.; Chempakan, B.; Rajagopal, V.
    The differences during the early stages of germination in the water absorption by the seednuts among three cultivars and one hybrid of coconut (Cocos nucifera L.) namely, WCT (Tall), MYD and COD (dwarfs) and WCTx COD is highlighted. The amount of water absorbed is higher in WC tall and the hybrid as compared to dwarfs. Growth parameters like the length of root and shoot as well as the volume of the haustorium are analysed. In addition, the partitioning of dry matter into husk, shell, kernel, haustorium, root and shoot were also determined. The essential role o/haustorium during the developmental changes as envisaged by the greater partitioning of dry matter is brought out.
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    In situ approach for rapid characterization to aid on farm conservation of coconut germplasm - A case study of two ecotypes from West coast of India
    (2013-12) Samsudeen, K.; Thamban, C.; Niral, V.; Augustine Jerard, B.; Rajesh, M.K.; Manjula, C.; Devadas, K.; Anitha Karun
    Characterization and evaluation of coconut germplasm have conventionally been undertaken in ex situ gene banks, which take a minimum duration of fifteen years. On the other hand, utilization of coconut populations in situ can effectively reduce the time required for characterization of the populations. Hence, a concept to make a paradigm shift in the existing approach of coconut germplasm characterization is advocated in this study with a view to broaden the conservation base and facilitate inclusion of identified diverse ecotypes. The methodology has been applied to identify, locate and characterize two tall coconut ecotypes viz., Bedakam and Kuttiyadi, from northern Kerala. Agronomic traits, viz., higher number of nuts per palm, higher copra content and better performance under marginal management conditions along with adaptation to the environment, were the major reasons for preference of these ecotypes among the farmers. Comparison of the two ecotypes revealed that the traits, trunk girth, length of internode, number of leaves, number of bunches with nuts, number of nuts, shell weight, husked fruit weight and fruit weight were higher in Kuttiyadi than in Bedakam ecotype. On the other hand, number of leaf scars per meter, length of inflorescence, fruit breadth, husk weight, nut cavity volume and copra weight were higher in Bedakam compared to Kuttiyadi ecotype. Relevance, utility and importance of the study are discussed from the perspective of effective utilization of the coconut diversity in situ and their possible further use in coconut improvement efforts through conservation strategies.
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    Morphological and molecular characterization of Kuttiyadi ecotype of coconut (Cocos nucifera L.)
    (2012-11) Manjula, C.; Samsudeen, K.; Shafeeq Rahman; Rajesh, M.K.
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    Solubilization And Utilization Of Seed Reserves During The Germination Of Coconut (Cocos Nucifera L.)
    (1993) Manjula, C.; Rajagopal, V.; Chempakam, B.
    The time taken for germination differs in coconut, depending on the cultivars. In this paper, the solubilization and utilization of seed reserves are monitored during the early stages of germination in two late germinators namely, West Coast Tall(WCT) and the hybrid WCT x Chowghat Orange Dwarf (COD) and in two early germinators namely, COD and Malayan Yellow Dwarf (MYD). As germination proceeded, marked changes occurred in the seed reserves like total lipids, proteins, amino acids and carbohydrates. There was a rapid increase in the total sugars, reducing sugars and starch in the haustorium, which revealed the assimilation of sugars during the development of embryo. Similar changes were noticed in the contents of lipids and protein in both the kernel and haustorium. The role of hydrolytic enzymes like amylase, invertase, lipase, esterase and protease in the solubilization and utilization of seed reserves is also clearly brought out.