2019 Volume 12 Issue 2 Pages 59-64
In order to obtain large size fruit, the relationship between fruit weight and flowering date, and number of fruit per cluster and cumulative temperature in ‘Natsutayori’ loquat (Eriobotrya japonica (Thunb.) Lindl.) were investigated. The mean fruit weight exceeded 60g when flowering from mid-November to the beginning of January, but took place at its smallest when it occurred in mid-January. The fruit weight was slightly larger in the two fruit per cluster than in the 3 and 4 fruit per cluster. As the flowering date became later, the fruit shape index increased, and consequently the shape of its longitudinal section became circular from a short oval one. Both the number of days to ripening and the cumulative temperature, based on 0℃ from flowering to ripening quadratically, correlated with the fruit weight, which was at its largest, when the number of days to ripening and the cumulative temperature, based on 0℃, was 145-160 days and 1,750-1,900℃･day, respectively. When the threshold temperature of the cumulative temperature was changed from 0 to 13℃, the coefficient of variance was the smallest at 10℃, with a cumulative temperature of 532℃･day.