EFFECT OF VINE BUD LOAD ON BUD BEHAVIOR, YIELD, AND CLUSTER CHARACTERISTICS OF AUTUMN ROYAL SEEDLESS GRAPEVINES

This study was conducted through the seasons of 2013 and 2014 to determine the optimum bud loads/ vine for Autumn Royal seedless "grapevines. Three years old uniform vines were uniform chosen and pruned to four levels of bud load, namely (32, 42, 52 and 60 buds/ vine). With fruiting spur at 2, 3 and 4 buds per spur The results showed that the percentage of bursted buds was decreased significantly by increasing bud load /vine in the two seasons of the study. Data also indicated that 42 buds/ vine were more suitable for Autumn Royal seedlessgrapevines to produce good yield and fruit quality. On the other hand, 32 buds/vine or 60 buds/vine were unfavorable science it produced rather clusters. In addition, pruning Autumn Royal seedless "grapevines to 42buds /vine by leaving 21 spur  with 2 eyes/spur or leaving 14 spur with 3 eyes per spur resulted a high yield and good quality, reduced cluster compactness and reduced shoot berries %,  gave the greatest cluster weight, berry firmness, adherence, T.S.S and anthocyanin content. Increasing bud load increased number of cluster/vine and yield but reduced cluster weight. Vines pruned to 32 buds / vine gave the greatest C/N ratio of the canes. Whereas vines pruned to 60 buds / vine showed higher percent of T.A than the other levels of bud load and cane length