Relative efficiency of cane characters in selection for cane yield in sugarcane (Saccharum spp. hybrid)

Abstract

The present investigation was attempted to develop selectron indices and to estimate the gains through discriminant function over direct selection for cane yield at 300 and 360 days. Similarly attempts were also made to construct simultaneous selection indices involving various combinations of characters and to estimate the genetic advance and relative efficiencies. The 28 genotypes of sugarcane representing the spectrum of variability in commercial sugarcane varieties released from Sugarcane Breeding Institute (ICAR), Coimbatore (TN) and clones selected by other Sugarcane Research Stations in the country were tested during 1995-96 at Sugarcane Breeding Institute, Coimbatore. These clones are complex allopolyploids with components of Saccharum officinarum L. , S. spontaneum L., S. barberi L. and S. sinense L. genomes. The crop was sampled by harvesting half at the 300 and 360 days after planting. Data were recorded on number of millable canes per plot, cane thickness, cane length, internode length, internode number, single cane weight and cane yield per plot. Genotypic and phenotypic variance and covariance were used for the calculation of regression coefficients (bi values) using different character combinations, considering cane yield as dependent and its parameters as independent variables as suggested by Robinson [1] and Smith [2]. The means and variability for the parameters studied at 300 and 360 days are presented in Table 1. The existence of high variability for the parameters indicate the possibility of a higher response through selection.