Management of coffee rust and brow eye spot using cultural and chemical control

Abstract

Brazil is the largest producer of arabica coffee in the world and diseases are the main causes of losses in coffee production. In Central America and Mexico, rust (Hemileia vastatrix) caused progressive losses in the production of 45% in the harvests from 2011 to 2014, triggering a socioeconomic crisis for these countries. However, the main cultivars are genotypes susceptible to rust and brow eye spot. In order to participate as much as the initial use of a disease rate, companies should make use of integrated disease management. This study is a plant after process of epidemiological and control of the epidemiological and control of microbiology in the area of plantation and fences. In the first experiment, five phosphorus doses (0.1, 0.5, 1, 2 and 4 mmol L-1) were combined with five doses of boron (0.1, 0.5, 1, 2 and 4 mmol L-1). The severity data were integrated in AACPSC regarding the dry weight of the samples and the foliar nutrient contents. The significant interaction between P and B and dietary intensities were observed at doses 2.0 and 2.0 mmol L-1 of P and B, respectively. The highest dry weight (5.7 g plant-1) was found in the lowest dose of P (0.1 mmol L-1). In addition, the P supply influenced the foliar levels of P, Cu, Fe, Ca and B. In the second experiment, the aim of the study was to evaluate the severity of brown eye spot in coffee plantations subjected to different drip irrigation and fertilization management. The study was carried out in Lavras-MG, Brazil, in a plantation of the cultivar MGS Travessia. Disease assessments were performed monthly from March 2012 to June 2014. The experimental design was a randomized block design with 12 treatments. The irrigation treatments were the control, without irrigation, irrigation all year, suspension of irrigation for 30 days in July, and for 70 days between July and September. The fertilization treatments were: i) recommended rate of NK fertilizer, ii) high rate of NK plus P and iii) high rate of NK. The severity of the disease were integrated in AUDPC. There was a difference in AUDPC in the evaluated years, reflecting the biennial characteristic of the coffee crop. There was no significant interaction between irrigation and fertilization. However, when irrigation and fertilization treatments where analyzed separately, the suspension of irrigation for 70 days between July and September in 2012 favored brown eye spot and in the same year the high rates of NK increased productivity. In the third experiment, the objective of the study was to evaluate the effect of fungicide mixtures on fungus resistance management and to verify manganese and zinc supply via Mancozeb. The experiment was implemented in two areas in 2017 and 2018 and six treatments were evaluated. Five evaluations of rust, brow eye spot and enfoliation were carried out in each evaluation year. The data were integrated in Area Under the Rust Progress Curve (AACPF), brow eye spot (AACPC) and leaf growth (AACPE). The fungicides controlled the diseases and provided greater coffee planting. The fungicide Mancozeb + Azoxystrobin + Ciproconazole provided manganese and leaf zinc. The highest yields were observed in Mancozeb + Azoxystrobin + Ciproconazole at 2.5 kg ha-1 and Piraclostrobin + Epoxiconazole at the dose of 1.5 L ha-1 in the year 2018 and the average of the years 2017/18.