Clonal evaluation of crosses by adopting family selection in sugarcane.

Abstract

Family selection has been adopted in sugarcane breeding programs as an indirect method of selection of superior clones in the early stages of selection among seedling progenies. In this study, 53 sugarcane families were evaluated for yield and quality parameters in three clonal stages at Sugarcane Breeding Institute, Coimbatore, during 2003-2008 seasons. Families were evaluated in replications and individuals were selected based on visual appraisal for yield parameters and Brix from selected families. Individual selection rate within families ranged from 10 - 30. Elite clones (40%) were selected from best families, viz. Co 7201 x Co 86002, Co 98010 x Co 94019, Co 98010 x Co 99006, Co 94012 x Co 99006, Co 86002 x Co 90018, Co 8371 x Co 86002, Co 8371 x CoC 8001 and Co 740 x Co 88025 with progressively fewer clones being selected from moderate to average families (Co 62260 x Co 6418, Co 837 x Co 94008). Individual selection within families based on brix % along with visual grading was found the best. The parents Co 62260 and Co 837 identified during earlier decades performed poorly when compared with crosses involving recently identified parents indicating the need for changing the base population. The study helped in generating information on breeding potential of parents in crosses for their long term use in hybridization programme. The study suggests adoption of a selection intensity of 40% for selection of best individuals in the top 10 families and 10 - 25% in the other families. Family selection at different clonal stages in combination with visual selection and individual clonal selection was advantageous in the selection of superior families and elite recombinants for exploitation in breeding programmes