Interaction of root confinement and fruiting in peach.
Mandre, O., Rieger, M,, Myers, S.C., Seversen, R. and Regnard, J.L.
Journal of the American Society for Horticultural Science. Volume 120, Number 2, Mar 1995. Pages 228-234.
1995
บทคัดย่อ
Fruiting and nonfruiting 'Washington' peach trees were grown in 2.4- (small) or 9-liter (large) containers to determine the influence of root confinement and fruiting on vegetative growth, fruit growth and quality, CO2 assimilation (A), and carbohydrate contest. Shoot length, fruit diameter, A, and leaf carbohydrates were measured weekly. Thirteen, weeks after transplanting, trees were divided into roots, shoots, leaves, and fruit for dry weight measurement. The dry weight of all organs except fruit was reduced by root confinement, and only the weight of stems formed the previous season was not reduced by fruiting. Fruit dry weight was 30.0 g/tree for large- and small-container treatments, causing the yield efficiency (g fruit/g total dry wt) to be 50% higher for confined trees. Fruit red color, weight, and diameter were unaffected by root confinement, but higher flesh firmness and a more green ground color of the fruit surface from root-confined tree suggested that confinement delayed maturity. Vegetative growth was not reduced by lack of nonstructural carbohydrates in confined trees. A was reduced by root confinement on only the first of 11 measurement dates, whereas fruiting increase A on 5 of 8 measurement dates before fruit harvest. Fruit removal reduced A by 23% and 31% for nonconfined and confined trees, respectively, within 48 h of harvest. Leaf starch, sucrose, sorbitol, and total carbohydrate levels were negatively correlated with A when data were pooled, but inconsistent responses of A to carbohydrate content indicated that factors other than feedback inhibition were also responsible for the reduction in A on nonfruited trees. We hypothesized that a physiological signal originating in roots of confined trees reduced vegetative growth without reducing fruit growth.