Coffee Science_v.18, 2023
URI permanente para esta coleção${dspace.url}/handle/123456789/13916
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Item New vegetation index for monitoring coffee rust using sentinel-2 multispectral imagery(Universidade Federal de Lavras, 2023-12-29) Castro, Gabriel Dumbá Monteiro de; Vilela, Emerson Ferreira; Faria, Ana Luísa Ribeiro de; Silva, Rogério Antônio; Ferreira, Williams Pinto MarquesCoffee Rust (Hemileia vastatrix) is considered the primary coffee disease in the world. The pathogenic fungus can find favorable environmental conditions in different countries, constantly threatening coffee producers. The previous detection of the incidence of coffee rust in a region is crucial because it provides an overview of the disease’s progress aiding in coffee plantations management. The objective of this work was the development of a vegetation index for remote monitoring of coffee rust infestation. Using satellite images from the MSI/Sentinel-2 collection, the Machine Learning classifier algorithm - Random Forest, and the cloud processing platform - Google Earth Engine, the most sensitives bands in coffee rust detection were determined, namely B4 (Red), B7 (Red Edge 3) and B8A (Red Edge 4). Thus, the Triangular Vegetation Index method was used to create a new vegetative index for remote detection of coffee rust infestation on a regional scale, named Coffee Rust Detection Index (CRDI). A linear regression model was created to estimate rust infestation based on the performance of the new index. The model presented a coefficient of determination (R²) of 62.5%, and a root mean square error (RMSE) of 0.107. In addition, a comparison analysis of the new index with eight other vegetative indices commonly used in the literature was carried out. The CRDI obtained the best performance in coffee rust detection among the others. This study shows that the new index CRDI has the robustness and general capacity to be used in monitoring coffee rust infestation on a regional scale.Item Temporal progress of coffee leaf rust and environmental conditions affecting severity in Veracruz State, Mexico(Universidade Federal de Lavras, 2023-03-28) Pale-Ezquivel, Ivan; Lagunes, Ricardo Musule; Pineda-López, Maria del Rosario; Alarcón-Gutiérrez, Enrique; Sánchez-Velásquez, Lázaro RafaelCoffee is an important crop in Mexico. Unfortunately, coffee production has been affected by coffee leaf rust (CLR). For Veracruz, the second state in Mexico with the major production of coffee, there are available reports of weekly CLR severity, but these are only informative without in-depth inferential analysis. We analyzed variations of CLR severity along the year in Veracruz with data from municipal weekly reports provided by Mexico’s federal government phytosanitary epidemiological monitoring coffee program. We selected reports dated in 2018 from nine municipalities and after calculations of mean monthly severity values, we conducted a one-way ANOVA (months as factors) of severity data. We compared this information with other coffee-producing regions. Additionally, we explored the association of temperature, rainfall, and altitude with CLR severity using Principal Component Analysis and multiple linear regressions. Temperature and rainfall data were obtained from Mexican National Meteorological Service. We found that CLR severity in October, November, December, and January (months of harvest period) was significantly higher than values from March-June. During the harvest period, coffee plants allocate resources mainly for fruiting which competes in resources for other tasks such as defense and leaf growth, so this competition of resources can explain the positive relationship found between fruit load and CLR severity. This monthly variation of severity was similar to those reported in Chiapas, Guatemala, Colombia, Uganda, and Ethiopia. Our model (R2 = 0.948) showed a significant and negative effect of minimum and maximum temperature (in a range from 9.9 – 15.5 °C and 18.5 – 26.5 °C, respectively) on CLR severity, while the effect of rainfall (in a range from 32.0 – 359.9 mm) and médium temperature (from 14.3 – 20.5 °C) was positive. With our study, we suggest applications of fungicides in March-June when coffee plantations are in leaf phenophase.Item Evaluation of a prototype of soil thermal solarizer for control of gall nematode in the production of coffee seedlings(Universidade Federal de Lavras, 2023-02-23) Uchôa, Francisco Paiva; Vieira Junior, José Roberto; Fernandes, Cléberson de Freitas; Rocha, Rodrigo Barros; Espíndula, Marcelo Curitiba; Rudnick, Vaneide Araújo de Sousa; Silva, Dvany Mamedes da; Freire, Tamiris Chaves; Sangi, Simone Carvalho; Mariobo, Solange Aparecida RodriguesIn coffee crops at Rondônia State of Brazil, there is an increase in phytonematode epidemics.Since most local coffe nurseries at Rondônia use soil as substrate for seedling production, this work aimed to test the minimum exposure time at 60 ºC to control of root-knot nematodes Meloidogyne incognita in soil by means of solar heating, using a solarizer, in an adapted version for better heating perfomance. The used solarizer prototype was built of a wooden box covered with metal sheets, thermal blankets, painted black, with aluminum pipes of 0.5 cm in diameter at the bottom of the box that circulates the water heated by the collector box. The soil was inoculated with a suspension of 1000 eggs + J2 of M. incognita per liter and placed in equipment with a capacity of 150 liters. Exposure times at a minimum temperature of 60 °C were evaluated, with 14 treatments: C1 (non-inoculated and not autoclaved), C2 (inoculated), C3 (non-inoculated and autoclaved) T0’, T15’, T30’, T45’, T60’, T180’, T360’, T720’, T1440’, T2880’ and T4320’ . The temperature was measured every 15 minutes using a skewer-type digital thermometer. The soil was removed according to the exposure time, and placed in 8-liter pots, in which clone 125 and BRS 2357 coffee seedlings, susceptible to M. incognita , were transplanted and growing in a greenhouse for 180 days. The experimental design used was DIC, with 6 replications, each seedling as na experimental unit. Reproduction factor (FR), number of eggs per plant (NOGR) and number of galls per gram of root (NGGR) were evaluated. The FR, NOGR and NGGR variables reduced with exposure time. All treatments showed an effect to control the population of M. incognita in infected soils, with 100% efficacy of pathogen eradication from the T45’ treatment, 60 minutes of exposure is recommended for the production of Coffea canephora seedlings. Taken together, thir work showed the high potential of thr solorizer to contribute in the root-knot nematode control to seedling production.