Effect of Prohexadione calcium, 6-benzyl amino purine and 6-furfuryladenine on vegetative growth and fruit quality in apple

Abstract

It is well established that the climatic change is altering yield in fruit trees. This adversity reflects, among others, extreme temperature modifications in northern Mexico. This effect modifies negatively the physiology of apple trees (<i>Malus domestica</i> Borkh.), originating excessive shoot growth and a decrease in flower bud formation. In this study, Prohexadione-Ca (P-Ca), 6-benzyl amino purine (BAP) and N6-furfuryladenine (kinetin) were evaluated on shoot and reproductive growth in Golden Delicious apple trees in Arteaga Coah., Mexico. A completely randomized design with 12 treatments was used. These were: Control, Prohexadione calcium (Ca-P) at doses of 150, 300 and 450 mg/L, cytokinins (CK) [6-benzylaminopurine (BAP) + N6-furfuryladenine (kinetin)] at concentrations of 150 and 300 mg/L, and combinations of these bioregulators to the doses mentioned. The experimental unit consisted of two trees per treatment. Variables evaluated were: shoot growth, fresh weight, vitamin C, and carotenoid concentration in fruit and return bloom. P-Ca drastically reduced shoot growth and increased return bloom. Carotenoids and vitamin C concentrations were increased in fruits with this retardant. Cytokinins applied individually or in combination with P-Ca caused increments on flower bud formation, fruit weight, and carotenoid and vitamin C concentrations in harvested fruits.