Effect of African rice gall midge on yield and its components on inter-specific rice progenies, using correlation and principal components as analysis tools

Inter-specific rice progeny lines (Oryza glaberrima × Oryza sativa) were evaluated for African rice gall midge resistance at two locations in 2010 cropping season. The experiment was made of 16 rice progeny lines including the two parents; FARO52 and Tog 7442 and a known susceptible check FARO 37. The experiment was conducted in the lowland experimental fields of National Cereals Research Institute at Badeggi and Edozhigi. The fields were laid out in a randomized complete block design in three replications. Gall midge was scored at 42 and 63 days after transplanting, other parameters collected include plant height, days to 50% flowering and grain yield. Principal component analysis indicates that the first three principal components accounted for 64.5% of the total variation in the population across the two locations. Correlation analysis showed a negative correlation (P=0.05) between percentage midge infestations at 63 DAT with number of panicle squared meter. Grain yield did not correlate significantly (P=0.05) with percentage gall midge infestation at 42 and 63 DAT, but there was a significant positive correlation (P=0.05) between percentage gall midge infestation at 42 and 63 DAT. Result revealed that FAROX 521-E-900-1, FAROX 521-H-559-1 and FAROX 521-H-686-1 are found to be resistance to African rice gall midge (AfRGM), while FAROX 521-E-430-1 and FAROX 521-H-433-1 gave a better yield potential under midge infestation and could be used for further genetics studies.