Narrow-sense Heritability of Fruit Characters in Japanese Pear (Pyrus pyrifolia Nakai).

We analysed the fruit weight, flesh firmness, soluble solid content and pH of fruit juice to obtain information on the inheritance of these characters, using a Japanese pear seedling population consisting of sixteen families and their parental cultivars and selections. The average values for the fruit weight, flesh firmness, soluble solid content and pH of fruit juice in the parental cultivars and selections were 354 g, 4.5 Ibs, 12.4 % and 4.94, and t.he coefficients of variation for the fruit weight, flesh firmness, soluble solid content and pH of fruit juice in these cultivars and selections were 0.35, 0.09, 0.05 and 0.05, respectively. The average values of family means for three years in each family ranged from 202 g to 423 g for the fruit. weight, 4.3 lbs-5.1 Ibs for the flesh firmness, 12.3 %∼ 13.3 %for the solube solid content and 4.76-5.26 for the pH of fruit juice, with the overall average values of means of sixteen families for these characters being 272 g, 4.8 Ibs, 12.7 % and 5.05, respectively. The average value of the range of yearly fluctuations in each family was 47.2 g' for the fruit weight, 0.48 Ibs for the flesh firmness, 0.95 % for the soluble solid content and 0.12 for the pH of fruit juice. . Statistically significant parent-offspring correlation coefficients were obtained between mid-parental values and the values of family means for the fruit weight, flesh firmness, soluble solid content and pH of fruit juice, although they vvere different among the characters. The estimates of heritability for the fruit weight, flesh firmness, soluble solid content and pH fruit juice were in the range of 0.57 -0.82, 0.14- 0.56, 0.37- 0.50 and 0.58- 0.69. The average value of heritability for three years was 0.73 for the fruit weight, 0.29 for the flesh firmness, 0.42 for the soluble solid content and 0.64 for the pH of fruit juice. fruits