A STUDY OF THE ASSOCIATION BETWEEN EARLINESS, FRUIT SIZE AND EARLY YIELD IN DETERMINATE TOMATOES
The association between fifteen developmental characters and earliness, fruit size and early yield in six determinate tomato varieties was studied in 1958 to evaluate these characters as selection criteria. The number of ripe fruit produced by September 1 was used as the measure of earliness and the weight of ripe fruit as the measure of early yield.Number of fruit set on July 1 and on July 15 were associated with earliness and early yield in all varieties. In four varieties, days to three ripe fruit was negatively correlated with earliness; the association being strongest in the later varieties. Little association existed between earliness and days to first flower or days to first ripe fruit.Early yield was strongly associated with weight of first four ripe fruit in five varieties and with weight of ripe fruit produced on the first cluster, in three varieties. Fruit weight data taken at earlier stages showed little if any association with early yield.This study indicates that early large-fruited, high-yielding tomato lines can be selected through combining information on early fruit set and size of the first four ripe fruit.