EVALUATION OF INTRA-SPECIFIC HYBRIDS OF SACCHARUM OFFICINARUM FOR YIELD, QUALITY AND INCIDENCE OF YELLOW LEAF DISEASE

Improvement of parental clones of Saccharum officinarum L. through repeated cycles of intra-specific hybridization and selection was undertaken at ICAR-Sugarcane Breeding Institute (SBI), Coimbatore during 1987 to 1996. Thirty one clones selected from six polycrosses involving 13 parental clones of S. officinarum constituted cycle 1 (C1) population. Intermating among fourteen C1 clones followed by selection resulted in identification of 33 clones in cycle 2 (C2) population. Fourteen clones selected in C2 and C1 were inter-crossed. From the progenies, 50 clones were selected to constitute cycle 3 (C3) population. As the original parental clones of S. officinarum had low number of millable canes (NMC) and poor cane yield, in each cycle of selection emphasis was given to select progenies with high NMC, single cane weight and cane yield. The C1, C2 and C3 population, totalling 114 (designated as population-improved S. officinarum clones or PIO clones) were evaluated at ICAR-SBI Research Centre, Agali during 2015-16 and 2016-17 for NMC, single cane weight, cane yield per plot, brix%, sucrose% in juice and resistance to yellow leaf disease (YLD). Generation-wise improvement in the targeted traits was estimated. Significant improvement in NMC /ha (37.18 per cent), single cane weight (16.67 per cent) and cane yield (61.51 per cent) was achieved in two cycles of selection. Ten YLD-free improved clones with acceptable agronomic traits were identified for further use. They are: PIO 94-847, PIO 94-875, PIO 99-633, PIO 00-513, PIO 00-547, PIO 00-638, PIO 00-757, PIO 00-769, PIO 00-772 and PIO 00-840. These improved PIO clones would serve as new parental gene pool in the interspecific hybridization programmes and for diversifying the genetic base of commercial sugarcane varieties.