Browsing by Author "Regi Jacob Thomas"
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Item Application of RAPD markers in hybrid verification in coconut(2014) Rajesh, M.K.; Jerard, B.A.; Preethi, P.; Regi Jacob Thomas; Anitha KarunCoconut palms are classified into two major types, viz., ‘talls’ and ‘dwarfs’, which mainly differ in their pollination behavior of cross- and self-pollination, respectively. Due to this difference, getting true-to-type progenies of desirable tall and dwarf cultivars has always been a challenge. The conventional practice of selection of seedlings based solely on morphological traits often results in selection of out-crossed seedlings and undesirable off-types. In the present investigation, RAPD markers for the tall/dwarf trait were identified in coconut using a bulked DNA approach. Screening of tall and dwarf palm bulk DNA with 200 primers revealed a RAPD primer OPBA3 which was able to clearly differentiate both the tall and dwarf bulks. For validation, the primer was used to screen individual tall and dwarf coconut palms representing different geographic regions. The primer was also used to screen the parents and validate hybrids of Dwarf x Tall crosses.Item Authentication of coconut hybrids using RAPD analysis(2012-11) Rajesh, M.K.; Preethi, P.; Jerard, B.A.; Regi Jacob Thomas; Anitha KarunItem Cloning, characterization and expression analysis of NBS-LRR-type resistance gene analogues (RGAs) in coconut(2016) Kaitheri Edathil Rachana; Sudalaimuthu Asari Naganeeswaran; Thayale Purayil Fayas; Regi Jacob Thomas; Muliyar Krishna RajeshItem Cocoa as a potential intercrop in coconut in the root (wilt) disease prevalent tracts(2021-10) Shareefa, M.; Regi Jacob Thomas; MayalekshmiItem Coconut Tissue Culture: The Indian Initiatives, Experiences and Achievements(2017) Anitha Karun; Rajesh, M.K; Sajini, K.K.; Muralikrishna, K.S; Neema, M.; Shareefa, M.; Regi Jacob ThomasItem Coconut varieties: A promising Solution for Sustaining Environmental Equity(2018) Regi Jacob Thomas; Shareefa, M.Item Community Nurseries for producing quality coconut seedlings(2018-11) Aarathi, R.Bai.; Sreelekshmi, J.S; Shareef, M.; Regi Jacob ThomasItem Convergence Model for Establishing Decentralized Coconut Nursery : The Kallara Experience(2020-11) Bharath Mohan; Joseph Refin Jefri; Shareefa, M.; Regi Jacob ThomasItem Development of a RAPD-derived SCAR marker associated with tall-type palm trait in coconut(2013) Rajesh, M.K.; Jerard, B.A.; Preethi, P.; Regi Jacob Thomas; Fayas, T.P.; Rachana, K.E.; Anitha KarunCoconut palms are classified into two major types, viz. talls and dwarfs, based on plant stature. The selection of coconut seedlings in the nursery, presently relying solely on morphological markers, often results in selection of out-crossed seedlings. Hence, identification of molecular markers for distinguishing tall/dwarf character at an early stage of growth assumes importance. In the present investigation, a RAPD marker for tall-type palm trait was identified using a pooled DNA approach. Screening of tall and dwarf palm bulked DNA with 200 decamer primers revealed a primer OPA09, producing a unique band of around 260 bp exclusively in tall accessions. The primer was used for screening and validation in individual tall and dwarf coconut accessions representing different geographic regions. The band was present in all the tall accessions, but absent in the dwarfs. Furthermore, sequence characterized amplified region (SCAR) primers were designed from the unique RAPD amplicon. The primers produced a specific 260-bp amplicon in tall accessions, but not in dwarf accessions. The SCAR marker was utilized in assessing the purity of hybrid seedlings of D×T (Dwarf×Tall) cross. The results pave the way for ensuring genuineness/quality of hybrid seedlings of coconut.Item Diversification of coconut based farming system through community based organizations for income generation and sustaining productivity(2013-12) Krishnakumar, V.; Kalavathi, S.; Regi Jacob Thomas; George V. ThomasCommunity based organizations (CBO) were formed in three coconut growing areas in Kerala during 2005-2008 and through farmer participatory process, various technological interventions for diversification of cropping system appropriate to the local community as well as subsidiary enterprises were taken up for income generation. The interventions included (a) intercropping with various crop species (cash and food security crops) aiming at year round farm income, (b) subsidiary enterprise comprising of animal husbandry component, (c) product diversification and value addition of coconut and intercrops as well as, (d) recycling of waste biomass through vermicomposting. The project not only brought out significant change in area put under crop diversification by way of inter/mixed cropping, but also in the average income derived from such farming system. Significant improvement in income was achieved through crop and enterprise diversification. While inclusion of various intercrops improved the share by 83 per cent compared to the income from coconut alone, it was up by 195 per cent when subsidiary enterprises like rearing of live stock and value addition were also considered, thus indicating the sustainability of crop and enterprise diversification in the project areas. The significant reduction in the value of Herfindahl Index, a measure of diversification, from 0.70 to 0.57 signified the improvement in the extent of diversification in various CBOs. Diversification of crops and adoption of coconut-based subsidiary enterprises through CBOs were found to be ideal strategies for sustaining productivity and rural upliftment in terms of income generation.Item Diversification of livelihood for the marginal coconut farmers: A replicable model(2010) Kalavathi, S.; Krishnakumar, V.; Regi Jacob Thomas; George V. Thomas; Maria Luz GeorgeItem Diversity in Coconut(2017-10) Regi Jacob Thomas; Shareefa, M.Item DNA amplification fingerprinting in coconut : protocol optimization and analysis of resistance to root (wilt) disease(2005) Jayadev, K.; Rajesh, M.K.; Devakumar, K.; Regi Jacob Thomas; Nair, R.V.; Parthasarathy, V.A.Item A durable pollination raincoat for hybridization during monsoon in coconut(2020) Devakumar, K.; Regi Jacob Thomas; Anitha KarunItem Enhancing planting material production in coconut through decentralised community nurseries(2022-07) Thamban, C.; Samsudeen, K.; Regi Jacob ThomasItem Enhancing planting material production in coconut through decentralised community nurseries(2020-10) Thamban, C.; Samsudeen, K.; Regi Jacob ThomasItem Identification and utilization of informative EST-SSR markers for genetic purity testing of coconut hybrids(2016-08) Preethi, .P; Rajesh, M.K; Rahul, C.U; Jerard, B.A.; Samsudeen, K; Regi Jacob Thomas; Anitha KarunCoconut palms are categorized into two forms, viz., ‘talls’ and ‘dwarfs’ which are being utilized to produce hybrids through the process of inter-varietal or intra-varietal crosses. Hybrid coconut seedlings are generally identified and selected based on morphological traits by plant breeders, which is quite difficult and requires expertise. Even minor errors in identification may adversely affect breeding programs in coconut, which is spread over many decades. In this study, we have utilized thirty EST-SSR markers, derived from existing coconut leaf transcriptome data, for screening polymorphism between eighteen coconut parental lines. The polymorphic primers capable of differentiating the parental palms were then utilized successfully for assessment of purity of hybrids derived from these parents. Thus, the current study demonstrates the utility of EST-SSR markers in determining the genetic purity of hybrids in coconut.Item Improving food and nutritional security of small and marginal coconut growers through diversification of crops and enterprises(2010) Kalavathi, S.; Krishnakumar, V.; Regi Jacob Thomas; George V. Thomas; Maria Luz GeorgeThis paper presents the impact of integrating interventions like nutrition gardening, livestock rearing, product diversification and allied income generation activities in small and marginal coconut homesteads along with nutrition education in improving the food and nutritional security as well as the income of the family members. The activities were carried out through registered Community Based Organizations (CBOs) in three locations in Kerala, India during 2005-2008. Data was collected before and after the project periods through interviews using a pre-tested questionnaire containing statements indicating the adequacy, quality and diversity of food materials. Fifty respondents each were randomly selected from the three communities, thereby resulting in a total sample size of 150. The data was analysed using SPSS by adopting statistical tools like frequency, average, percentage analysis, t – test and regression. Participatory planning and implementation of diverse interventions notably intercropping and off-farm activities along with nutrition education brought out significant improvements in the food and nutritional security, in terms of frequency and quantity of consumption as well as diet diversity. At the end of the project, 96%of the members became completely food secure and 72% nutritionally secure. The overall consumption of fruits, vegetables and milk by both children and adults and egg by children recorded increase over the project period. Consumption of fish was more than the Recommended Dietary Intake (RDI) level during pre and post project periods. Project interventions like nutrition gardening could bring in surplus consumption of vegetables (35%) and fruits (10%) than RDI. In spite of the increased consumption of green leafy vegetables and milk and milk products over the project period, the levels of consumption were still below the RDI levels. CBO-wise analysis of the consumption patterns revealed the need for location-specific interventions matching to the needs and preferences of the communities.Item In vitro regeneration of coconut plantlets from immature inflorescence(2019) Shareefa, M.; Regi Jacob Thomas; Sreelekshmi, J.S; Rajesh, M.K; Anitha KarunItem INFLUENCE OF TEMPERATURE, GERMINATION DURATION AND CULTIVAR ON IN VITRO POLLEN GERMINATION AND POLLEN TUBE GROWTH IN COCONUT (COCOS NUCIFERA L.).(2017) Chaturvedi, V. K.; Hebbar, K.B.; Chandran, K.P.; Regi Jacob Thomas; Shareef, M.; Nampoothiri, C.K.; Jinu Sivadasan