BEHVIOUR OF PRIME SEEDLESS GRAPEVINES GROWN UNDER SANDY SOIL CONDITIONS TO FOLIAR APPLICATION OF CHITOSAN

This study was undertaken three times during 2015 and 2016 seasons to test the effect of spraying chitosan at 50 to 800 ppm three times on vegetative growth, vine nutritional status, berry setting %, yield, shot berries % and berries quality of prime seedless grapevines grown under sandy soil condition. Carrying out three sprays of chitosan at 50 to 800 ppm had an obvious promotion on all vegetative growth aspects chlorophylls a & b, total carotenoids, N, P, K and Mg in the leaves, berry setting %, cluster weight, vine yield and berries quality relative to the control. A remarkable reduction on the percentage of shot berries was recorded with using chitosan treatments. Conclusively, the best results with regard to yield and berries quality of Prime seedless grapevines grown under sandy soil condition were obtained due to treating the vines thrice with chitosan at 200 ppm.