Published online by Cambridge University Press: 19 September 2011
Seventy cultivare of sorghum representing recently released varieties, hybrids, experimental varieties, lines bred for stalk-borer resistance and local resistant stocks were tested for stalk-borer resistance under artificial infestation during monsoon (July–October) season. There were significant differences among varieties for leaf-feeding injury, per cent ‘dead hearts’, number of holes and tunnels and per cent tunnelling. Released hybrids and local varieties were susceptible for different parameters. Thirteen varieties viz., SPV Nos. 35, 103, 107, 110, 135, 140, 192, 229, E 302, E 304, P 37, R 133 and CSV-8R were at par with resistant varieties for per cent tunnelling per plant. Long peduncle varieties were relatively susceptible.
Leaf-feeding injury, per cent ‘dead hearts’ and tunnelling parameters were not significantly correlated and independent of each and none of them could be related to grain yield. Number of holes, number of tunnels and per cent tunnelling were positively correlated. Thus, number of holes per plant or internode may be a good indicator of per cent tunnelling and can conveniently be used as a criterion for evaluating germplasm to stalk-borer (Chilo partellus Swin.) resistance. The varieties CSV-8R, SPV-35, SPV-103, SPV-140 and SPV-192 were identified as promising sources of resistance to stalk-borer.