SELECTION INDICES FOR CANE YIELD IN SUGARCANE

Abstract

Various selection indices were constructed for cane yield in a population of twenty two advanced sugarcane genotypes, tested in 4 location x 2 yearly environments. Cane yield contributing characters such as number of millable canes (NMC), stalk height, stalk thickness and stalk weight and the juice extraction per cent were used to estimate expected genetic gain from selection indices for cane yield, The selection index (51) with NMC, stalk height, stalk weight and juice extraction per cent and cane yield itself had maximum genetic gain (18.47%) over straight selection. The genetic gain of 51 with above five characters and cane thickness was 18. 44 percent. The genetic gains of SIs were v,ery low with any five characters excluding NMC (1.20%) or cane yield (6.04%). SIS with both NMC and cane yield had 16.97 per cent genetic gain over straight selection. Thus NMC and cane yield should be included in 51 for maximum cane yield. However, selection based on NMC, cane yield, stalk height, stalk weight and juice extraction percent was important for maximum improvement in cane yield.