Saha D.,Indian Institute of Natural Resins and Gums |
Saha D.,National Research Center on Finger printing
Indian Journal of Natural Products and Resources | Year: 2013
Schleichera oleosa (Lour.) Oken is a preferred tree-host of kusmi form of lac insect, Kerria lacca, which produces superior quality lac resin of commercial interest. Very low success rate of clonal multiplication of this tree is one of the major bottlenecks for supply of quality planting material for lac cultivation. In vitro multiplication of axillary buds although promise to produce large-scale clones of high-yielding lac hosts, establishment of aseptic node culture is one of the critical steps in standardization of micropropagation from mature S. oleosa plant. The seasonal influence on bud emergence, heavy microbial contaminations and phenolic exudations are the important factors observed in the present study that limits the establishment of axillary bud cultures in S. oleosa. Predominant fungal and bacterial contaminants were identified through morpho-cytological and DNA sequence analysis. The Murashige and Skoog's (MS) medium with 1.0 mg/L BAP and 1.0 mg/L silver nitrate showed best (83.33±13.61%) shoot initiation. Sub-culturing and elongation of the proliferated microshoots were possible on filter-paper-bridge soaked in liquid MS medium with 0.5-1.0 mg/L BAP, instead of agar-gelled MS media. Rooting of the axillary bud-derived shoots continued to be the major hurdle to achieve success in developing micropropagation protocol in S. oleosa.
Vanaja T.,National Research Center on Finger printing |
Vanaja T.,Kerala Agricultural University |
Singh R.,National Research Center on Finger printing |
Randhawa G.J.,National Research Center on Finger printing
Indian Journal of Agricultural Sciences | Year: 2010
A study was conducted during 2005 to understand genetic relationship at molecular level among a collection of rice (Oryza sativa L.) varieties and land races of Kerala using SSR markers. Twenty eight SSR markers were used to screen the genotypes. The 28 SSR markers loci revealed 73 alleles in 76 cultivars with an average of 2.61 alleles/locus. The number of alleles/locus varied between 1 and 8. Out of 28 SSR markers, 4 were monomorphic hence percentage polymorphism was 85.7. The size of allele amplified among the 76 cultivars varied from 130 to 1 180 bp. Cluster analysis was done using pair-wise Jaccard's similarity co-efficient which grouped 76 rice genotypes into 4 major clusters. Whereas 1 scented land race of Kerala, namely 'Gandhakasala' and the brown plant hopper resistant variety 'Ptb 20' were not grouped with any cluster. The genotypes 'Vytilla 2', 'Ptb 20', 'Deepti' and 'Malakkaran' were grouped in different clusters and observed to be genetically distant.