Studies on the sultana vine. VII. A comparison of crop regulation by pruning with crop regulation by disbunching

An experiment comparing crop regulation by pruning with crop regulation by disbunching is described. For three out of four seasons both methods of regulation gave similar yields, and only in one season did disbunched vines yield somewhat better than more severely pruned vines with the same number of bunches. This better yield appeared to be due to larger berries on the disbunched vines. Increased vegetative growth on the disbunched vines was not accompanied by improved fruit bud formation or by better bud burst in the following season. It is concluded that the leaf/fruit ratio has little effect on the yield of sultanas under Murray Valley conditions, and that methods of crop forecasting and regulation by pruning developed for this region should not be affected by the variation in leaf / fruit ratio to which they give rise.