M. SHANTHI PRIYA*, K.H.P. REDDY, M. HEMANTH KUMAR, V. RAJARAJESWARI, G. MOHAN NAIDU, R. NARASIMHULU, B. RUPESH KUMAR REDDY AND D. MOHAN REDDY

Department of Genetics and Plant Breeding, S.V. Agricultural College, Tirupati, Andhra Pradesh – 517 502, India.

ABSTRACT

Selection indices were formulated using seventy seven genotypes of sugarcane in second clonal stage considering theoretical yield of alcohol and seven of its component characters which showed high correlation with it. Among eight characters that were used to formulate selection indices, theoretical yield of alcohol (X1) was considered as dependent character while other characters viz., brix per cent (X2), sucrose per cent (X3), commercial cane sugar per cent (X4), juice purity per cent (X5), pol per cent cane (X6), total sugars per cent (X7) and commercial cane sugar yield (X8) were considered as independent variables. From the results, it is evident that to increase the alcohol yield selection should be mainly based on total sugars per cent as all the selection indices showing higher relative efficiency and genetic advance involved this trait. For indirect selection, the index involving the combination of five characters viz., brix per cent (X2), sucrose per cent (X3), juice purity per cent (X5), pol per cent cane (X6) and total sugars per cent (X7) which exhibited maximum relative efficiency of 523.98 with genetic advance of 12.14 could be considered for selection schemes to improve theoretical yield of alcohol. Inclusion of commercial cane sugar yield to this index increased the relative efficiency to 602.98 and genetic advance of 13.97.

KEY WORDS:  Selection indices, Sugarcane, Theoretical yield of alcohol,