INBRED LINE × TESTER ANALYSIS AND THE POTENTIAL OF INBREEDING IN STRAWBERRY BREEDING
The performance in fruit yield characteristics and fruit appearance of seven Premier S5 inbred selections was studied in their crosses with four tester varieties, Redcoat, Senga Sengana, Sparkle and Jerseybelle. Some of the progenies produced by crossing Premier S5, inbreds with testers were superior in a number of yield characters to those produced when Premier was crossed to the same testers. This suggests that inbreeding, although expensive and time consuming, may be a useful step in one type of approach to breeding for higher yield in the cultivated strawberry.General combining abilities of the inbred selections and of the testers were both significant for all but one character, while specific combining ability of inbreds × testers was significant for six of the eight characters. The estimates of general combining ability effects of the inbreds and the testers were found to be of limited value in predicting the most desirable single crosses. The significance of this is discussed together with a proposed procedure for exploiting inbreeding in strawberry breeding.