PREDICTION OF BREEDING VALUES FOR AVERAGE FRUIT WEIGHT IN MANGO

Fruit weight is considered an important factor determining consumer choice in mango and other fruit. In this study, breeding values for average fruit weight were predicted for 29 parents and their ancestors from a seedling progeny trial established in northern Queensland using multivariate linear mixed model approaches that incorporated a pedigree. The trial was conducted over 6 seasons from 1999/2000 to 2005/2006 assessing average fruit weight in 1615 progeny (an average of 433 progeny per season) from 40 families made up of 29 cultivar combinations. Different means, breeding values and residual effects were estimated for each season using a factor analytic approach. Average fruit weights were not significantly different among seasons, however, there was a significant (p = 0.003) effect of year of planting. Additive genetic effects were large with average narrow sense heritability of 0.79. Family effects were very small and not significant. Breeding values were very strongly correlated among seasons (r_g = 0.98), however, there was no strong correlation in non-genetic effects on the average fruit weight of progeny among seasons (r_e = 0.29) suggesting that environmental impacts on average fruit weight may differ between years. The estimated breeding values indicated that on average, progeny from crosses with the cultivars ‘Keitt’ and ‘Kent’ produced the largest fruit and progeny from ‘Creeping’ and ‘Williard’ produced the smallest fruit. Implications for mango breeding are discussed.