GENETIC ENHANCEMENT OF SUGARCANE (Saccharum sp. hybrids) FOR RESISTANCE TO RED ROT DISEASE AND ECONOMIC TRAITS

Abstract

The present experiment was conducted at Sugarcane Breeding Institute (ICAR), Coimbatore to generate diverse genetic stocks for resistance to red rot disease caused by Colletotrichum falcatum Went. and other important economic traits. This study was carried out with progenies obtained from 39 crosses involving 45 parental clones of interspecific and intervarietal origin. The interspecific origin involves diverse forms of Saccharum officinarum and S. spontaneum that are hitherto unutilized in the breeding programme. The progenies were evaluated for resistance to red rot disease and economic traits such as cane yield and quality. Out of 39 crosses investigated for race specific resistance as a qualitative trait, 18 crosses showed a simple Mendelian segregation of monogenic nature. Parent progeny regression analysis suggested that about 50% of the variation in the population could be attributed to additive genetic variance (horizontal resistance). Two crosses involving susceptible parents viz., 971235 (S) x Co 1148 (S) and Co 88028 (S) x Co 775 (S) contributed 28-30% resistant progenies. These transgressive segregants are likely to be stable in their resistance due to additive genetic action and could be used as donor parents in red rot resistance breeding programmes for imparting race non-specific resistance. The present investigation has also identified some specific cross combinations for yield, quality in addition to red rot resistance for further exploitation in breeding programme.