Behaviour of "Tanaka" loquat and influence of naphtaleneacetic acid on fruit setting in the Jordan Valley [1989/90 - 1990/91; morphology; vegetative and reproductive growth; growth patterns; fruit weight and volume]

Vegetative growth of "Tanaka" loquat trees under conditions prevailing in the Jordan Valley tended to be in three flushes: summer, autumn and a peak one occurring in spring. Shoot growth in these flushes followed linear growth pattern. In the first season 61.1% of shoots continued elongation, reduced in the second season to 10.3%. In both seasons flower buds appear in early Aug. Flowering started at the third week of Nov and the second week of Dec for the first and second season, respectively. 38.9% of shoots produced flower buds in the first season, while in the second - 89.7%. Fruit setting occurred in the last week of Dec for both seasons. Final fruit set percentage was 4.9% and 5.32% in the first and second season respectively. Fruit growth after setting was slow in the winter and quick toward ripening in spring. Fruit colour development started at the second half of Mar, while ripening was delayed until the first half of Apr: the fruits were allowed to maturate fully (orange colour) on the tree. Average number of ripe fruit per panicle was 3.88 and 4.51 for the first and second season, respectively. However, in the second season, the number of panicles was 2.5 times more than in the first season as this increase had negative effect on average fruit weight which was 25.94 gr in the first and 18.63 gr in the second season. Estimated yield for each tree in the first season was 3.37 kg and 7.39 kg in the second. Furthermore, fruit quality was investigated, regarding seed number and TSS%.The average seed number ranged from 2.99 to 3.07. TSS ranged from 11.37% to 12.3%. NAA at 20 ppm improved fruit weight through thinning effect when applied at full-bloom stage in case of heavy crop season, while it had no significant effect in case of light crop season. NAA had no effect on fruit quality regarding seed number and TSS. Also, it had no effect on fruit growth pattern