Coffee Science - v.14, n.3, 2019

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12417

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Association of indaziflam and oxyfluorfen in coffee pre-transplantation
(Editora UFLA, 2019-07) Pucci, Laís Franchini; Fukada, Paulo Massaharu; Pereira, Gustavo Antônio Mendes; Alves, Deivide Patrik; Gomes, Carolina Alves; Reis, Marcelo Rodrigues dos
Weed management in the pre-transplantation of coffee plants is an essential condition for the future success of the crop. Currently, the producer has few options to perform chemical management at this stage. Therefore, one of the solutions that is being used is the tank mixing of products proven efficient with new products on the market, such as indaziflam. The objective of this study is to know the selectivity of indaziflam, associated or not with oxyfluorfen, in coffee pre-planting and its effectiveness in weed control. Thus, the following treatments were tested in the field: indaziflam (25 g ha -1 a.i.), indaziflam (50 g ha -1 a.i.), oxyfluorfen (960 g ha -1 a.i.), indaziflam (25 g ha -1 a.i.) + oxyfluorfen (960 g ha -1 a.i.), indaziflam (50 g ha -1 a.i.) + oxyfluorfen (960 g ha -1 a.i.), plus a weeded and a non-weeded control. All treatments caused low intoxication in the seedlings, but without impairing the development and morphological variables of the plants. The treatments were efficient in controlling the species Bidens pilosa L., Commelina benghalensis L., Urochloa decumbens, Emilia fosbergii and Melampodium perfoliatum until 68 days after application. At 104 days, it was observed that there was a reduction in the efficiency of the products. It is concluded that the associated use of indaziflam and oxyfluorfen does not cause intoxications capable of interfering with the development of coffee plants. The association of these herbicides or their isolated applications is efficient in the control of weeds in the pre-transplantation of coffee plants, and the choice of the best management strategy is dependent on the weed community present in each area.
Indaziflam application in newly transplanted arabica coffee seedlings
(Editora UFLA, 2019-07) Gomes, Carolina Alves; Pucci, Laís Franchini; Alves, Deivide Patrik; Leandro, Vitor Alves; Pereira, Gustavo Antônio Mendes; Reis, Marcelo Rodrigues dos
Weed management is one of the main and most problematic cultural practices used in coffee plantations. Slow growth, broad spacing associated with scarce registered products for weed control at an early crop stage, are the main problems faced by producers. Therefore, it is desirable for new herbicide molecules to be registered for this crop, as is the recent case of indaziflam. This study aimed to know the influence of indaziflam on the morphological characteristics of coffee plants and to propose alternatives to reduce its effects on plants. Therefore, the effects of this herbicide on two arabica coffee cultivars were studied, as well as the association of this herbicide with protection of the seedling collar (PVC pipes and bovine manure). Controls on weeds, possible injury on seedlings and effects on the main morphological characteristics of coffee plants were evaluated. Although treatments with the use of indaziflam cause intoxication in the seedlings, a reduction in plant damage was observed over time, and the damage was insignificant. In general, it was observed that cultivar IBC 12 suffered minor injuries, but it is more sensitive to the presence of indaziflam, since it presented greater damage in the morphological variables. The use of manure with the PVC pipe can be an alternative to reduce the effects of this herbicide, as it reduced the effects of the product on the root system of this cultivar. It is concluded that the application of indaziflam causes mild symptoms in coffee plants independent of the planted cultivar. Indaziflam causes reduction in seedling morphology, and this effect is dependent on the cultivar used. The use of manure associated to the PVC pipe can be an alternative to reduce the effects of indaziflam, mainly in the root system of coffee plants.
Initial stages of infectious process of Pseudomonas syringae pv. garcae in coffee leaves
(Editora UFLA, 2019-07) Souza, José Otávio Gusmão de; Pozza, Edson Ampélio; Belan, Leônidas Leoni; Freitas, Marcelo Loran de Oliveira; Oliveira, Júlia Marques
Bacterial blight of coffee (Pseudomonas syringae pv. garcae) (PSG) has been causing damage and losses to coffee growing. However, initial stages of the infectious process should be described in order to understand the relationship cycle and to propose efficient management strategies. This study described the initial stages of infectious process of the PSG in coffee leaves over time. The bacterial penetration sites studied were stomata, leaf margins, and wounds. Coffee seedlings received 50μL inoculum suspension at marked points on the abaxial face and leaf margins, and around wounds. By 30 minutes, 1, 3, 6, and 12 hours after inoculation, leaf disks collected at inoculated points were analyzed with scanning electron microscopy. One hour after inoculation, bacterial groups could be seen as result of cell multiplication. Subsequently, the number of grouped bacteria increased proportionally over time. A growing population concentration was found near stomata, wounds, epidermal appendages, and wax layer on leaf margins and leaf tip. From these places bacteria were positioned in their long axis starting from structures, thus created a population gradient and displacement flow toward penetration sites. Initial stages of infectious process occurred in all penetration sites, thus it was not possible to determine a preferred pathway.
Selection of fungal isolates with potential for phosphate solubilation and formulation of inoculant for coffee crops
(Editora UFLA, 2019-07) Chalfoun, Sara Maria; Angélico, Caroline Lima; Resende, Mário Lúcio Vilela de; Moraes, Graziella Evaristo de
The dependence on chemical fertilizers for the future of agriculture will result in additional soil health losses, possibility of water contamination and continued currency avoidance due to the increasing dependence on imports. The indiscriminate use of synthetic fertilizers has polluted the soil and watersheds, destroying useful microorganisms and insects, what makes crops more susceptible to diseases. Considering this critical scenario, microorganisms have stood out as a potential alternative for maintaining the productivity, reliability and sustainability of the global food chain. In order to increase the productivity and/or reduce the amount of fertilizers, as well as to meet the requirements for the use of low-solubility phosphorus sources, microorganisms were isolated from the rhizosphere and artificially cultivated. Subsequently, they were selected regarding their potential for solubilizing phosphorus and incorporated into a low-cost matrix. A microbial inoculant was thus developed and tested in a coffee crop. It was possible to formulate an inoculant based on an isolate selected from Aspergillus niger, using an inactivated seed and sodium alginate as matrices. It was also observed that there was a greater correlation between the evaluated parameters and increasing doses of the inoculants when Araxá apatite was used as source of phosphorus, proving the importance of the inoculants as release factors and availability of phosphorus in the case of sources less soluble, giving Brazilian agriculture greater autonomy in the input market.
Selectivity of fluazifop-p-butyl in young coffee plants
(Editora UFLA, 2019-07) Voltolini, Giovani Belutti; Castanheira, Dalyse Toledo; Menicucci Netto, Pedro; Alecrim, Ademilson de Oliveira; Rezende, Tiago Teruel; Guimarães, Rubens José; Gonçalves, Adenilson Henrique
Weed control is fundamental in coffee cultivation due to their big interference, competing with the crop for water, light and nutrients. Among the control methods used, chemical control is highlighted, as a function of its high efficiency and low cost. However, due to application failures, herbicide drift phytotoxicity is common. Aiming at the search for selective active ingredients in coffee plants, the objective in this study was to evaluate the selectivity of the active ingredient Fluazifop- p-butyl on the young coffee plants, and its effects on plant morphology, anatomy and physiology. The experiment was carried out in a greenhouse, with ‘Topázio MG 1190’ coffee plants (Coffea arabica L.), cultivated in pots with a capacity of 11 L substrate. The statistical design was randomized block design (RBD), with four replications and four doses of the herbicide, making up 16 experimental plots. Each plot consisted of three plants. The treatments were: 0%; 50%; 100% and 200% of the recommended commercial dose of the herbicide Fluazifop-p-butyl. The evaluations were performed at 120 days after application of the treatments. Morphological, physiological and anatomical characteristics were evaluated. Regardless of the evaluated characteristic, there was no difference between the doses of the herbicide. There were no visual phytotoxicity symptoms in the young coffee plants that received the herbicide Fluazifop-p-butyl. The growth of the coffee plants and the physiological and anatomical characteristics were not altered due to the application of the herbicide Fluazifop-p-butyl.
Yield of Coffea arabica grafted onto Coffea canephora in soils infested with nematodes in Mexico
(Editora UFLA, 2019-07) López-García, Francisco Javier; Cruz-Castillo, Juan Guillermo
The total of three consecutive years of fruit production was evaluated in six coffee cultivars (Coffea arabica L.) propagated by seed and grafted onto Robusta (Coffea canephora var. Robusta). The plantations were established at 640 m, 920 m, and 1340 m altitude in the central region of the Veracruz State, Mexico. The coffea plants were established in soils naturally infested with nematodes. Grafted plants had higher production than those propagated by seed. Fruit production was higher at 640 m and 920 m than at 1340 m for the two types of propagation. The cultivars Colombia Brote Café and Colombia Brote Verde had the highest fruit yield regardless of the propagation methods; in contrast, Pacamara, had the lowest. The grafted coffee plants that were planted at 1340 m had a yield reduction of 27% in comparison with those at 640 and 920 m. When the Costa Rica 95 variety was grafted, it achieved fruit yield similar to Colombia Brote Verde and Colombia Brote Café. Pacamara produced almost 28% more fruit when it was grafted onto Robusta.