Heterosis for growth, yield and fruit quality traits in papaya

摘要

An experiment was conducted during 2016-2017 to determine the magnitude of heterosis in papaya for growth, yield and fruit quality traits. A total of eight genotypes consisting three hybrids along with their five parents were evaluated in a Randomized Block Design with three replications. Appreciable heterosis was found over better over mid parent in traits like days to fruit maturity, number of fruits per plant, fruit yield, fruit shelf life, fruit firmness, antioxidant activity of fruit,total carotenoid content and lycopene content in desirable direction. A hybrid, of progeny of Red Lady (Self) x Pusa Nanha (14.57%) showed significant relative heterosis for yield, whereas none of the hybrids were recorded with better parent heterosis. Two hybrids, Red Lady (Self) x Pusa Nanha (2.93%) and Pune Selection 3 x P-7-9 (22.13%) was observed with high heterosis for number of fruits per plant. All three hybrids exhibited heterosis in negative direction for days to fruit maturity. For fruit shelf life at ambient temperature, hybrid Red Lady (Self) x P-9-5 (3.12%) exhibited better parent heterosis, whereas all three hybrids showed positive mid parent heterosis for the same trait. All three hybrids showed positive mid-parent heterosis for traits like number of fruits per plant, shelf-life, total phenolic content and antioxidant activity. The hybrid Red Lady (Self) x Pusa Nanha exhibited better parent and mid parent heterosis for total carotenoid and lycopene content along with total phenolic content and antioxidant activity. Moreover, none of the hybrids showed positive heterosis for TSS, leaf length, fruit weight, fruit diameter and fruit length. However, hybrid Red Lady (Self) x Pusa Nanha has shown moderate heterosis for important economic traits and same may be exploited further to develop a commercial hybrid of papaya.