MANIPULATION OF FRUIT WATER AND DRY MATTER CONTENT BY TREATMENTS APPLIED DURING EARLY AND LATE STAGES OF FRUIT DEVELOPMENT IN KIWIFRUIT

A.R. Morton, D.J. Woolley
During early and late stages of fruit development, cells within the fruit of Actinidia deliciosa have increased capacity for expansion and water uptake. To investigate fruit water uptake during these periods, 14 mature T-bar vines were subjected to a range of treatments designed to manipulate the osmotic and water potential gradients to the fruit. Treatments included supplying vines with surplus water, trunk girdling, foliar application of N-(2-chloro-4-pyridyl)-N’-phenylurea (CPPU), and foliar applications of urea. Surplus water during both early and late stages of fruit development significantly reduced the concentration of dry matter in the fruit (DM%) (p<0.05) by increasing fruit water uptake by approximately 7%. In girdled vines, there was a similar response to surplus water in non-CPPU treated fruit, but little effect in CPPU-treated fruit. The largest response to girdling was found in CPPU-treated fruit from vines not given surplus water (control). A smaller increase in water uptake in CPPU-treated fruit from vines given surplus water (wet) suggests that the capacity for cell expansion was more fully realised by the effects of CPPU and girdling vines. In non-CPPU treated fruit from girdled vines foliar sprays of urea during early fruit development increased both DM% (p<0.01) and DM accumulation (p=0.06). In CPPU-treated fruit from girdled vines the effects of urea on DM and water accumulation were larger but lacked statistical significance. The results suggest that foliar urea may be useful for increasing fruit FW and DM%.
Morton, A.R. and Woolley, D.J. (2011). MANIPULATION OF FRUIT WATER AND DRY MATTER CONTENT BY TREATMENTS APPLIED DURING EARLY AND LATE STAGES OF FRUIT DEVELOPMENT IN KIWIFRUIT. Acta Hortic. 913, 309-313
DOI: 10.17660/ActaHortic.2011.913.40
https://doi.org/10.17660/ActaHortic.2011.913.40
Actinidia deliciosa, dry matter percentage, fruit quality, water content
English

Acta Horticulturae