Combining ability analysis of strawberry cultivars in complete diallel mating

Abstract

The study was conducted to find out the breeding value of seven strawberry parental genotypes (Confectura, Gorella, Sweet Charlie, Chandler, Selva, Addie and Ofra) in a full-diallel mating design (Griffing’s method I) in terms of general, specific and reciprocal combining ability (GCA, SCA and RECA) effects for several important horticultural traits. Significant differences were found in general combining ability (GCA), specific combining ability (SCA) and reciprocals effects for most of the traits. Parental lines Gorella and Chandler exhibited good general combining ability for number of flowers, number of fruits and yield/plant and suitable for breeding cultivars with more number of fruits, flowers and yield. For early fruit maturity ‘Gorella’ and ‘Addie’ exhibited good general combining ability. For short duration of flowering and early flowering ‘Selva’, ‘Addie’, ‘Ofra’, Confectura were good general combiners, including ‘Gorella’ for early flowering. Parental lines Chandler, Selva and Sweet Charlie were good general combiners for TSS and ‘Addie’ for titratable acidity. The F1 hybrids Chandler x Gorella, Chandler x Selva, Chandler x Sweet Charlie, Selva x Sweet Charlie, Selva x Confectura, Gorella x Ofra, Sweet Charlie x Confectura, Selva x Gorella and Selva x Confectura due to their significant SCA effects were considered as good specific combiners for number of flowers, number of fruits and yield. SCA effect for days taken to early flowering were negatively significant for hybrids viz., Chandler x Gorella, Chandler x Confectura, Chandler x Addie, Chandler x Ofra, Selva x Gorella, Selva x Sweet Charlie, Selva x Confectura and Sweet Charlie x Addie. These hybrids could be utilized in breeding programmes for imparting early flowering in genotypes. SCA effect for duration of flowering were negatively significant for hybrids Chandler x Confectura, Chandler x Sweet Charlie, Chandler x Gorella, Chandler x Ofra and Chandler x Addie. F1 hybrids Chandler x Gorella, Selva x Confectura and Selva x Sweet Charlie were good specific combiners for early fruit maturity/harvesting. Chandler x Gorella, Chandler x Selva and Confectura x Addie were good specific combiners for TSS. Among reciprocal crosses, Addie x Chandler, Addie x Selva, Addie x Gorella were good combiners for number of fruit and flowers per and yield/plant. Whereas, for early flowering and early fruit maturity, ‘Confectura x Chandler’ was good reciprocal combiner. ‘Addie x Confectura’, ‘Ofra x Selva’ and ‘Gorella x Selva’ were good reciprocal combiners for shortening duration of flowering.