ICRISAT Archival Report 2006 - The seedlings of success in the ...

for localized breeding and testing for sorghum midge resistance. A total of 155 conventionally bred midge resistant
lines plus 5 checks were evaluated in a preliminary trial at Alupe, Kenya in the long rainy season 2006 under natural
infestation. These lines were crosses between MR No.s 2, 3, 4, 6, 7, 8, 10, 17, 21 22 from ICRISAT India with IS
8613, IS 21016 and AF 28. The trial had two plantings; one early and the other 2 weeks after normal planting to
ensure adequate insect pressure for midge damage evaluation. The first planting had a mean score of 3.4 midge
damage on a 1-9 scale. 91 entries had scores of 1.0-3.0 midge damage showing high levels of resistance. Eighty
eight entries had grain yields between 1.3 and 4.6t/ha and these high yielding lines corresponded to the 91 lines with
low midge damage, an indication that at this site midge resistance enhanced grain yield. The second planting had a
mean score of 7.4 midge damage (1-9 scale) and 29 lines showed moderate levels of resistance to midge with scores
of 4-6 (1-9 scale) and with a grain yield potential of over 1.0 t ha -1 (trial mean 0.981 t ha -1 ). In the second planting,
all check varieties except for IS 8613 had grain yield