This study was designed to found the effect of summer pruning on improving
the response of Thompson Seedless grapevines to dormex application. Dormex was
sprayed at 4% on 20 january. Summer pruning treatments iduded : head suckering,
pinching the main shoots and topping the laterals. The results showed that dormex
spraying at 4%, either alone or combined with summer pruning, hastened bud burst
by 17 and 16 days compared with the control during the two seasons respectively .
All applications increased the percentage of bud burst, fertility and fruit set . All
treatments also, seemed to be very effective concerning improving vegetative growth
(leaf area) , coefficient of wood ripening, yield as well as physical and chemical
properties of berries compared with the untreated vines. The most effective
treatments were dormex + summer pruning followed by dormex alone. This study
confirmed the benefeit of carrying out summer pruning in combination with dormex for
Thompson Seedless grape cv .