Peach rust progress and its interference with vegetative plant growth and yield in two production systems in Brazil
The integrated fruit production (IP) is a sustainable system for peach production that involves a reduction of fungicide sprays, appropriate cultural practices and crop monitoring. Peach rust (Tranzschelia discolor) causes defoliation, resulting in premature budding and blossoming of the trees in the subsequent season. Peach rust control under IP rules was evaluated during two seasons in a commercial orchard. Disease incidence and severity under IP system rules were contrasted with disease intensity in an orchard that used the local production system (LP), and with an untreated control (UC) orchard where no fungicides were applied and served as a reference for disease intensity. Disease progress, premature defoliation and components of vegetative growth (length and diameter of shoots) and yield (number of fruits on each shoot) were evaluated. The area under the disease progress curve for incidence (AUDPCI) was lowest for IP grown plants in both crop seasons. A logistic model was fit to the disease incidence data. The initial inoculum (y0) was lowest under IP and LP conditions in the first season, and defoliation was least under IP. There was no difference between the IP and LP systems for shoot diameter or fruit production. The correlation (r) between y0 and AUDPC of rust severity was high (0.75 and 0.87, respectively) (p≤0.05). The correlation between y0 and shoot length was negative (-0.92, p≤0.05). The IP system provided better peach rust control compared to LP.
Kowata-Dresch, L.S., Amorim, L. and May-De Mio, L.L. (2021). Peach rust progress and its interference with vegetative plant growth and yield in two production systems in Brazil. Acta Hortic. 1304, 273-282
epidemic, control, Tranzschelia discolor, crop protection, management