Coffee Science_v.18, 2023
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Resultados da Pesquisa
Item Inhibition of respiration by light in Coffea arabica(Universidade Federal de Lavras, 2023-12-29) Oliveira, Indira Pereira de; Barbosa, João Paulo Rodrigues Alves Delfino; Saleska, Scott; Pennacchi, João Paulo; Prohaska, NeillDescribing gas exchange between plants and the atmosphere is essential to improve current estimates of fluxes and carbon stocks. Light is directly related to gas exchange; when plants are under low light intensities, there is an increase in photosynthetic quantum yield and, consequently, in respiratory rate. That means there is an apparent inhibition of respiration under high light intensity, a phenomenon known as the Kok effect. Considering the effect of light and leaf age, the aim of this study was to describe the physiological responses of daytime gas exchange related to leaves of different ages in Coffea arabica L. cv. Catuaí Vermelho, seeking to identify leaf respiration inhibition by light. The experiment was conducted at the Universidade Federal de Lavras, Minas Gerais, Brazil. Leaves were measured using an infrared gas analyzer (IRGA; LI- 6400XT, LI-COR, Lincoln, NE, USA) and the fluxes were measured to create a light response curve in “in situ”, thus obtaining photosynthetic parameters, used to estimate light and dark respiration, also the rate of inhibition of leaf respiration by light throughout the leaf age. The assimilation (A_sat) and quantum efficiency did not differ among young, mature, and old leaves, showing that photosynthetic process was not affected by leaf age; however, light and dark respiration were higher in young and mature leaves than in old leaves. Inhibition of respiration by light was similar among leaf ages, assuming the occurrence of inhibition of respiration caused by light (the Kok effect).Item Caffeine and chlorogenic acid content of Coffea canephora cultivars in different environments(Universidade Federal de Lavras, 2023-11-19) Rocha, Rodrigo Barros; Alves, Enrique Anastacio; Tadeu, Hugo Cesar; Teixeira, Alexsandro Lara; Bizzo, Humberto Ribeiro; Antoniassi, Rosemar; Pacheco, Sidney; Santiago, Manuela Cristina Pessanha de AraujoCoffee plants of the Coffea canephora species are currently grown in tropical regions throughout the world, and both greater yield efficiency and greater beverage quality are important considerations. The aim of this study is to characterize the content of caffeine and of chlorogenic acids of C. canephora cultivars in different environments. According to the maturation cycle of each clone, samples of cherry coffee were collected from ten cultivars evaluated in the environments of Porto Velho, RO, Ouro Preto do Oeste, RO and Manaus, AM. These environments with contrasting characteristics represent most of the coffee fields established in the Am and Aw climate types in Latossolos Vermelhos and Latossolos Amarelos, typical of the Western Amazon. The results were analyzed considering the factorial design to quantify the effects of genotypes, of environments, and of the genotype × environment interaction (GE) on the caffeine and chlorogenic acid contents. Regardless the significant GE effects, the caffeine and chlorogenic acid content exhibited predominantly genetic control. In comparison to the caffeine, the chlorogenic acid content was more affected by the environment effects, displaying more variations in the genotypes performance across the environments. The significant positive association between the caffeine and chlorogenic acid contents favors the selection of plants that simultaneously have greater or lower contents of both traits. The selection of clone BRS3210 resulted in a selection gain of 14.99% in caffeine content, while the cultivation of the clone BRS3193 yielded a selection gain of 10.81% in chlorogenic acid content. The selection of clone BRS2299 resulted in a reduction of 21.85% in caffeine content and of 9.15% in chlorogenic acid content.Item Phosphorus fixation and its relationship with soils chemical properties of the coffee zone of Huila, Colombia(Universidade Federal de Lavras, 2023-11-01) Poveda, Vanessa Catalina Díaz; Sadeghian, SiavoshAdsorption is one of the critical processes in phosphorus (P) availability in plants. In the coffee crop (Coffea arabica), the highest dose of P is supplied in the vegetative phase, so its management is fundamental to guarantee the optimum growth of plants. The aim of this work was to determine the P fixation capacity and its relationship with the soil chemical properties of the Huila coffee zone, Colombian department, with the largest area planted with coffee. The adsorption isotherms were obtained by equilibrating the soil with 30mL of KH2PO4 solution dissolved in a 0.01M CaCl2.2H2O, containing concentrations of P between 50 and 4.200 mg kg-1. The P adsorption was measured for 60 soil samples collected from the five main cartographic units of the department: Campoalegre, El Recreo, La Cristalina, Saladoblanco, and San Simón. The data fitted to the linear and nonlinear Langmuir model forms. It was found that the soils of the region have a variable P fixation capacity, with values of q (adsorption at 0.2 mg L-1 in solution) between 8 and 1330 mg kg-1 and b (maximum adsorption capacity) from 117 to 3916 mg kg-1, without finding an association with the evaluated soil units. A correlation of q and b was found between Al3+, Al3+ saturation, pH, Ca2+ and Mg2+, and base saturation.Item Productivity and physical quality of grains from Coffea arabica L. in a tropical high-altitude climate in Brazil(Universidade Federal de Lavras, 2023-11-19) Martins, Adriana Novais; Turco, Patricia Helena Nogueira; Araújo, Humberto Sampaio de; Firetti, RicardoThe coffee plant is extremely important for Brazilian agribusiness as it generates foreign exchange earnings and employment throughout the production chain. In this study, we evaluated the production and parameters related to the quality of 18 Coffea arabica L. cultivars grafted onto the Apoatã IAC 2258 cultivar, in seven consecutive harvests. The experiment was installed in 2014 and carried out for seven harvests, in Fazenda Recreio in the municipality of Vera Cruz, state of São Paulo, Brazil. We used a randomised block design (DBC), with three experimental replications, which were conducted in 54 plots. We analysed productivity, yield, and grain size parameters. The data were evaluated by the analysis of variance (ANOVA) and the mean values were used to conduct the Scott-Knott and Tukey test. The results showed that in all the cycles, the characteristics evaluated showed significant differences among the cultivars. The ratio between the residual mean squares of the analysis of variance was less than 7:1 for all the characteristics evaluated, which allowed us to compare the seven harvests with each other. The cultivars IPR 100, Obatã IAC 1669–20, IPR 107 and IAC 125 RN performed the best, as determined by the parameters evaluated, and thus, we recommend these cultivars for growing coffee tropical high-altitude climate in Brazil.Item Reduction of frost damage to coffee trees under agroforestry systems(Universidade Federal de Lavras, 2023-10-03) Santoro, Patricia Helena; Morais, Heverly; Kitzberger, Cintia Sorane GoodFrosts affect coffee production in Brazil, with effects on commodity prices around the world. Agroforestry systems are strategies to reduce the effects of frost on coffee trees. To date, this study has evaluated the largest number of tree species in coffee tree AFSs in Brazil in the same experiment. The objective was to identify tree species that can protect coffee trees against frost damage in agroforestry systems. The study was conducted in Londrina, Paraná, Brazil. Each treatment consisted of coffee trees associated with one of the following tree species: Moringa oleifera, Croton floribundus, Trema micrantha, Gliricidia sepium, Senna macranthera, Heliocarpus popayanensis, and Mimosa scabrella, as well as a control of coffee trees in monoculture. The experimental area was affected by frost that damaged the coffee plants fifteen months after planting. Immediately thereafter, the dendrometric characteristics of the trees were evaluated. After 30 days, the defoliation and mortality of the trees were evaluated. The phytometric characteristics of the coffee trees were evaluated 12 months after the frosts. Six of the seven tree species were evaluated for the first time for their ability to protect coffee trees against frost. Even at an early stage of development, T. micrantha and H. popayanensis provided increased protection of coffee trees, reducing the defoliation and mortality of coffee trees. The main protective factor was the canopy area of these species, which provided a high rate of tree cover. The development of coffee trees after frosts was favoured by the shading of the species, with the exception of M. scabrella. The AFSs with T. micrantha and H. popayanensis constitute an alternative that allows the mitigation of frost damage to coffee plants in regions prone to this climatic stress, reducing defoliation and mortality.Item Coffee plant diseases affected by nutritional balance(Universidade Federal de Lavras, 2023-05-02) Pozza, Edson Ampélio; Pozza, Adélia Aziz AlexandreIn recent years, sustainability has become a priority in agricultural production programs throughout Brazilian territory due to the need to ensure food security and environmental quality. Diseases continue to be a factor limiting sustainable agricultural production, due to the great need for chemical defenses for their control. Thus, it is indispensable to make use of alternative management techniques to reduce the use of such chemical defenses and to increase resistance of plants to diseases. It is known that mineral nutrients affect plant resistance to diseases, and effective physical and biochemical response of plants to pathogens is determined by adequate concentrations of mineral elements in the plant tissues. This review presents the most recent information related to the mode of action of the nutrients in the host-pathogen interaction and individual action in the control of plant diseases with the use of essential nutrients, as well as other elements considered beneficial, such as Si. It also reports on the use of some of these mineral nutrients in control of the main diseases of the coffee plant that occur in Brazil, especially rust, cercosporiosis or brown eye spot, phoma leaf spot, and bacterial blight. In addition, contradictory and satisfactory results are found in the literature on the use of mineral nutrients in control of different diseases, including coffee diseases.