SELECTION OF SOMACLONES RESISTANT TO ALTERNARIA BLIGHT IN SESAME (SESAMUM INDICUM L.) THROUGH IN VITRO CELL LINE METHOD
Indian Journal of Fundamental and Applied Life Sciences
To achieve somaclones resistant to Alternaria blight of sesame, in vitro cell line selection was carried out by incorporating partially purified pathotoxin, on an incremental basis of 100 ppm, starting from 100 to 1000 ppm concentrations derived from culture filtrate of pure culture of Alternaria sesami pathogen to MS media supplemented with NAA @ 0.5 mg/l, BAP @ 1.5 mg/l and Kinetin @ 1.5 mg/l using the callus of six susceptible genotypes (E8, Gulbarga locals white and brown, Tumkur locals
... , Tumkur locals white and brown and W-II) and one resistant genotype (RT-273; identified resistant through field screening). Calli of susceptible genotypes survived only up to 300-ppm concentration whilst the callus of resistant genotype survived up to 700-ppm. The callus of RT-273 survived and proliferated in all the bottles when co-cultivated with the calli of all susceptible genotypes which died at 400 ppm concentration. Calli of all genotypes were dead when exposed to UV rays for six hrs continuously. A total of 33 calli were recovered when callus of susceptible genotypes were exposed to UV rays for one hr followed by plating on MS media supplemented with 1000 ppm, of which only 15 somaclonal calli responded for sub-culture. Regeneration is underway. The difference in response has been discussed in the light of intrinsic resistant nature of RT-273 genotype.