The effect of crop load and rootstock on dry matter and carbohydrate partitioning in peach trees (Prunus persica Batsch).

摘要

The effect of crop load on dry matter partitioning was studied on three-year-old peach (cv. Early May Crest) trees grafted on GF677 (P. persica x P. amygdalus) and Penta (P. domestica) was studied in a field experiment conducted in Lamezia, Italy. Fruit thinning was carried out 10 days after fruit set to produce different crop loads. Trees were sampled destructively in two seasons and then sampled for dry matter and carbohydrate analysis. At the end of the fruit development period, in the first year, crop efficiency (number of fruit per trunk cross-sectional area) was correlated to tree dry matter production, and the increase in crop efficiency decreased vegetative and root growth. Two consecutive years of heavy crop reduced dry matter accumulation of trees. The percentage of dry matter partitioned to fruits decreased with the vigour of the rootstock. Starch content in the roots was lowest for cropping trees and was highest for Early May Crest/GF677 trees. Mean fruit weight decreased with crop efficiency and increased with the rootstock vigour.