Paternal and maternal effects on fruit and seed characteristics in cherimoya ( Annona cherimola Mill.)

Abstract

Studies were conducted to determine the effect of maternal and paternal parents on fruit and seed characteristics in cherimoya. Using two commercially important cultivars in California as maternal parents (‘White’ and ‘Booth’) and three cultivars as paternal parents (‘White’, ‘Booth’ and ‘Chaffey’), we found that both maternal and paternal parent cultivars had significant effects on quantitative and qualitative fruit and seed characteristics. Maternal cultivar had a significant effect on mean seed weight, fruit set, surface morphology of carpels, and the percentage of carpels with protuberances. Pollen parent cultivar also produced significant differential effects on fruit and seed characteristics or xenia. Pollen parent cultivar had significant effects on fruit characters such as fruit length, fruit weight and percentage fruit set. Seed characters significantly affected by pollen parent included seed weight per fruit, seed number and mean seed weight. Other fruit characters such as fruit diameter, length diameter ratio, grams of fruit flesh per seed, and days to maturity, although not significant at the P < 0.10 level, exhibited trends toward xenia. Fruits sired by ‘Booth’ pollen were longer, heavier, and had greatest seed number and seed weight per fruit as well as significantly higher fruit set. The pollen germinability of ‘Booth’ pollen based on the fluorochromatic reaction, however, was significantly lower than ‘White’ pollen, but not significantly lower than ‘Chaffey’ pollen germinability. Despite female and male effects on fruit and seed characteristics, there were no significant male-female interactions.