Department of Plant Breeding and Genetics, J. N. Agricultural University, Jabalpur-482 004
Selection indices were formulated in soybean (Glycine max (L.) Merril) using discriminant function technique. The maximum relative efficiency of 106⋅41 per cent over straight selection was recorded when number of pods per plant, days to maturity and number of primary branches were considered with yield. When yield and primary branches were retained and rest of the variables dropped, a comparable relative efficiency of 106% was obtained. Among selection indices consisting of components of yield only, the maximum relative efficiency of 104% was obtained when seed weight and number of pods per plant were combined with primary branches. This was followed by selection index consisting of plant height, pods per plant and days to maturity with a relative efficiency of 103%. Selection based on selection index was as good as selection based on yield itself in terms of efficiency.
