Screening of rice genotypes against bakanae disease caused by Fusarium fujikuroi Nirenberg
Bakanae is one of the newly emerged diseases of rice and is attaining the status of major disease in Kashmir. Fifty rice genotypes consisting of thirty six germplasm lines and fourteen commercial cultivars were screened under artificially inoculated field and controlled conditions. Of the test lines screened under field conditions, four (GS-88, GS-308, GS-20 and GSL-29) were found highly resistant, five (GS-79, GSL-302, GSL-19, SK-423 and SI-6) as resistant, eighteen moderately resistant and remaining twenty three moderately susceptible. In order to validate the resistance, 27 genotypes, found moderately to highly resistant under field screening, were further screened under artificially inoculated controlled conditions against 20 isolates of F. fujikuroi collected from diverse locations. Seed dip inoculation technique, standardised after evaluating various inoculation techniques, was employed for screening genotypes under controlled conditions. One test line (GS-88) was found resistant with average disease incidence of 18.2 per cent exhibiting resistant response against all the 20 test isolates, 10 genotypes viz., Mushk budgi, China-972, GS-79, GSL-302, GS-27, GSL-19, SK-421, SI-4, GSL-
225 and SI-6 with average disease incidence ranging from 31.2 to 39.5 were found moderately resistant with resistant response to 10 to 14 number of isolates and remaining 16 viz., Kamad, China-988, Chenab, SK-408, SK-404, GSL-20, GSL-29, GSL-311, SK-423, SI-V17, SK-292, GS-308, GS-20, GS-82, SK-406 and SK-407 showed moderately susceptible reaction with average disease incidence ranging from 40.5 to 54.2 per cent, having resistant response to less than 11 isolates. None of the lines showed highly resistant, susceptible and highly susceptible response.