POLLINATION TECHNIQUES FOR THE IMPROVEMENT OF GREENHOUSE TOMATO PRODUCTION IN TWO CROP CYCLES

Fruit set limits the productivity of the tomato crop in the greenhouse. In north Mediterranean conditions two tomato crop cycles (early and late) can be developed in the same year. Environmental constraints limiting pollination in the different cycles could advise the use of different pollination techniques, both from a productive and economical point of view. The aim of this study is to analyze whether flower vibration, bumblebee pollination, or auxin spraying, can improve fruit production of early and late tomato greenhouse crops. For both crop cycles, pollination with bumblebee resulted in the highest fruit production. The mechanical flower vibration technique and the auxin treatment significantly increased fruit production in the early crop, but they were ineffective in the late crop cycle. However, treating the early crop with auxins may affect fruit shape. All treatments were more effective in the early crop, carried out in spring, than in the late crop. The untreated plants developed the highest fruit weight and diameter in both cycles. Earliness was not affected by the treatments. The environmental conditions are determinant for the effectiveness of the treatment, and only the use of bumblebee is effective under hot climate.