GENETIC VARIABILITY FOR AGRO MORPHOLOGICAL TRAITS AMONG THE INTERSPECIFIC HYBRIDS OF SACCHARUM

The extent and pattern of variation for various agromorphological traits were studied in 1346 progenies of six crosses involving S. officinarum, S. spontaneum, S. robustum, Indian and foreign hybrids. The progenies along with the parents were evaluated for traits like tillering, plant height, number of millable canes (NMC), Hand Refractometer (HR) Brix %, internode length, pithiness and red rot resistance. We observed a considerable amount of variation among the progenies for all the traits. The initial tillering in all the progenies was very high compared to their parents and highest tiller count was in S. officinarum x S. spontaneum cross. Progenies were generally thin especially among the crosses with S spontaneum as male parent. The mean HR Brix % at 8th month of the progenies having S spontaneum in their parentage was low (8-10%) which needs further improvement through backcrossing with S. officinarum, the female parent. The hybrid progenies of some of the crosses showed heterotic vigour for traits like NMC, internode length and plant height. Many progenies of the crosses Azul de caza (S. officinarum) x IK 76-10 (S. spontaneum), IJ 76- 315 (S.officinarum) x IJ 76 280 (S. robustum), IJ 76-315 x IMP 558 (S. spontaneum) were resistant to red rot. The wild species of Saccharum are known to impart disease resistance; the study resulted in introgression of red rot resistance genes to the progenies from S. spontaneum and S robustum. The red rot resistant progenies can be further utilized in the back breeding program to improve the yield and quality traits.