Thidiazuron and gibberellic acid on fruit set and growth of partenocarpic and polinized fruits of 'Ataulfo' mangos.
Pérez-Barraza M. H., Osuna-Enciso T., Gutiérrez-Espinosa M. A., Santiago-Cruz M. de J., Avitia-García E., Cano-Medrano R.
Author Affiliation: Universidad del Estado de Durango, Durango, Mexico.
Interciencia 40 : 677-683
Abstract : In 'Ataulfo' mango, parthenocarpic fruit production is increasingly frequent in producing areas, decreasing yield and productivity up to 50%. The goal of the study was to find alternatives to promote fruit set and development on pollinated and parthenocarpic fruits. In experiment 1 (E1) we used: gibberellic acid (GA3; 50 mg.l-1) in simple applications at 0, 15, 30, 45 or 60 days after full bloom (DAB); Thidiazuron (TDZ; 50 mg l-1)+GA3 in repeated applications at 15, 30, 45 and 60 DAB; and control. In experiment 2 (E2): TDZ at 0 DAB combined with 1, 2, 3 and 4 applications of GA3 at 15, 15+30, 15+30+45 and 15+30+45+60 DAB; and control. In both experiments the design was completely random, six and eight repetitions, and a tree as experimental unit. Tukey (P?0.05) was used for means comparison. In E1, GA3 single application at 30 DAB and TDZ+GA3 in repeated applications at 15, 30, 45 and 60 DAF increased final fruit set by 47% compared to control; the combined treatment increased length (7 cm) and fresh weight (80 g) of parthenocarpic fruits, and increased yield by 52%. In E2, the final fruit set increased 56% with TDZ at 0 DAB combined with four applications of GA3, and length of parthenocarpic fruit increased (>8 cm) compared to control (7 cm). TDZ+1-4 GA3 applications increased fresh weight of parthenocarpic fruits (37-48%) and decreased 37% their presence with respect to control. Fruit quality was not affected. TDZ, apparently, is sufficient to initiate fruit growth although GA3 is required for its development.