Effect of Bud Load and Foliar Spraying of Putrescine on Vegetative Growth of Two Grapevine (Vitis vinifera L.) Cultivars Halawani and Zaitoni

The study was carried out during the growing season 2020 in a private orchards in the Uthmaniya village, Diyala governorate, Iraq on the two grape cultivars (Halawani and Zaitoni) to evaluate the response these cultivars to three levels of pruning( 80, 100 and 120 buds.vine -1 ) with a fixed number of canes (10 canes vine -1 ) and spraying with Putrescine 0, 200 and 400 mg.l -1 in the growth of the studied cultivars. The results showed that the bud load 80 buds vine -1 led to a significant increase in leaf area, chlorophyll content and content of NPK in leaf petioles, while spraying 400 mg.l -1 of Putrescine recorded significant increase in leaf area, leaves dry matter percentage, chlorophyll content, and NPK content in leaf petioles, as for the cultivars, the Halawani cultivar was significantly superior to the Zaitoni cultivar in the leaf area, dry matter percentage in the leaves, chlorophyll content and phosphorous content in leaf petioles, the interaction treatments gave a significant effect on all the studied traits over untreated control treatment.