Fundo de Defesa da Citricultura-Fundecitrus, Departamento de Pesquisa e Desenvolvimento, 14.807-040, Araraquara, São Paulo, Brazil.
Plant Dis. 2018 Feb;102(2):334-340. doi: 10.1094/PDIS-04-17-0537-RE. Epub 2017 Dec 4.
The period of citrus black spot (CBS) control used in South Africa (SA) and Australia, from October to January or February, has not been as effective in São Paulo (SP), Brazil. This study aimed to evaluate different periods of protection and determine the critical period for CBS control in SP. A field trial was carried out for two seasons in a mature Valencia sweet orange orchard located in Mogi Guaçu, SP. Spray programs with a total of 60, 100, 140, 180, and 220 days of fruit protection (DFP) were evaluated. CBS symptoms and fruit drop decreased exponentially as the length of the period of protection increased. The reductions in CBS intensity and crop loss with these programs ranged from 34 to 96 and 50 to 77%, respectively. The programs with 180 and 220 DFP, which protected the fruit from September to March and May, showed the highest cost benefit. The critical period needed for CBS control in SP is longer than that in SA and Australia. The results obtained with the present study are helpful for scheduling a more efficient and rational program for CBS control not only in SP but also in other tropical and subtropical regions with similar weather conditions.
柑橘黑斑病（CBS）在南非（SA）和澳大利亚的防治期为 10 月至 1 月或 2 月，但在巴西圣保罗（SP）的效果并不理想。本研究旨在评估不同的保护期，并确定 SP 地区 CBS 防治的关键时期。在 SP 市的 Mogi Guaçu 地区，一个成熟的瓦伦西亚甜橙果园进行了两个季节的田间试验。评估了总共有 60、100、140、180 和 220 天果实保护（DFP）的喷雾方案。随着保护期的延长，CBS 症状和落果率呈指数级下降。这些方案对 CBS 强度和作物损失的降低幅度分别为 34%至 96%和 50%至 77%。保护期为 9 月至 3 月和 5 月的 180 和 220 DFP 方案表现出最高的成本效益。SP 地区 CBS 防治所需的关键时期比 SA 和澳大利亚长。本研究的结果有助于制定更有效和合理的 CBS 防治计划，不仅在 SP，而且在其他具有相似天气条件的热带和亚热带地区。
