Development and evaluation of backcross progenies of improved Saccharum spp for yield and quality traits

Abstract

Forty one improved Saccharum officinarum, 29 improved S. spontaneum, 27 improved S. robustum and 37 commercial hybrid clones were utilized in this genetic base broadening programme. PIO 88-100, PIO 90-202, PIO 00845, PIO 88-100, PIO 88-110, PIR 88-3350, PIR 88-327, PIR 96-258 and PIR 96-285 were good combiners for quality and yield traits. The programme created abundant genetic variability with genetic improvement for quality and yield parameters in the nobilized populations and the derivatives showed significant differences for cane yield and quality traits. Frequency distributions for yield and quality characters tended towards normality. The correlations among the characters indicated that there was a possibility of introgressing desirable characters from the improved germplasm. Backcross progenies exhibited higher values for most of the yield-related traits analyzed in comparison with the improved parents. In the improved S. officinarum x improved S. spontaneum group, even though there was an increase in number of millable canes, cane weight also increased considerably in first generation (31.5%). This resulted in higher cane yield which ranged from 52.4 t/ha to 101.25 t/ha in the population. About 12% of the BC1 families exhibited 23.5% higher cane yield. In the improved S. officinarum x improved S. robustum group, first stage nobilized hybrids showed an improvement of 12.25 % and 8.50% for sucrose % at 300 and 360 days over the improved S. robustum parents. BC1 showed improvement for both yield and quality parameters with an improvement of 21.91% and 14.79 % for sucrose % at 300 and 360 days respectively. The study also suggested further back crossing (BC2, BC3 and BC4 ) with commercial hybrids in this group to generate new gene pool for future breeding.