Ciência e Agrotecnologia
URI permanente para esta coleção${dspace.url}/handle/123456789/9885
Navegar
4 resultados
Resultados da Pesquisa
Item Rock powder application combined with bacterial inoculation enhances the early growth of coffee plants(Editora UFLA, 2025-03-14) Corrêa, Jessiane dos Santos; Araújo, Dayane Aparecida de Oliveira; Rodrigues, Allieksiei Castelar Perim Souza; Brito, Orlando Gonçalves; Gusmão Júnior, Genilson Rodrigues; Rodrigues, Tatiana Tozzi Martins SouzaThe use of rock powder combined with nutrient-solubilizing and growth-promoting bacteria represents a promising alternative for nutrient supply to the soil and improved crop development. This study aimed to evaluate the development of coffee seedlings treated with rock dust and inoculated with Bacillus species. Six types of rock powder (slate, black slate, gneiss, kamafugite, pyroxenite, and a mixture of mica schist and granite) were added to standard fertilizer in the presence or absence of a Bacillus mixture (Bacillus subtilis and Bacillus amyloliquefaciens) during coffee cultivation. We measured plant height, stem diameter, leaf number, shoot and root dry biomass, and nutrient levels in the soil and coffee leaves after. In the kamafugite treatment, adding a bacterial mixture increased plant height. When the bacterial application was considered alone, it resulted in an 85% increase in the plants’ total dry biomass. Rock powder and bacteria showed a substantial interaction effect, particularly for nutrients. Gneiss and kamafugite treatments increased phosphorus availability in the soil, whereas bacterial presence boosted calcium and magnesium content. The combination of nutrient-solubilizing and growth-promoting bacteria and rock powder improved soil chemical properties and the early development of coffee plants.Item Pseudomonas coronafaciens pv. garcae and P. amygdali pv. tabaci isolated from coffee plants cause diseases in different species(Editora UFLA, 2025-06-16) Raimundi, Melina Korres; Souza, Ricardo Magela de; Guimarães, Sarah da Silva Costa; Alvarenga, Ariane de Souza; Ribeiro, Daniel Henrique; Resende, Mário Lúcio VilelaBacterial halo blight and bacterial leaf spot have similar symptoms in coffee plants, and the etiological agents Pseudomonas coronafaciens pv. garcae (Pcg) and P. amygdali pv. tabaci (Pat) have very similar colony morphologies and biochemical characterizations, which makes it difficult to provide a correct diagnosis. To date, Coffea arabica is the only known natural host of Pcg, while Pat affects a wide range of host plants. However, no studies have yet been conducted to test the pathogenicity of Pcg strains in Pat hosts or Pat strains from different hosts in coffee plants. The objectives of this study were to evaluate the virulence level among Pcg strains and to perform cross-inoculation tests to confirm the hosts specificity for Pcg and Pat. In the virulence tests, there was variation in aggressiveness among Pcg strains. The reference isolate (CFBP 1634) and seven Pcg strains considered more aggressive were selected for cross-inoculation testing on different Pat hosts. All the Pat strains, regardless of the host of origin, caused disease in the coffee seedlings and Pcg strains caused disease in Phaseolus vulgaris, Cucumis sativus, Carica papaya, Aster sp., Coffea arabica, Celosia plumosa and Desmodium incanum. Therefore, there is no host specificity for Pcg and Pat, using artificial inoculation. These results are important for the beginning of the knowledge of the host range of Pcg and may contribute to the development of strategies to manage the disease.Item Trolox equivalent antioxidant capacity of Coffea arabica L. seeds(Editora UFLA, 2022-08-08) Ferreira, Iara Alves; Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Vilas Boas; Ricaldoni, Marcela Andreotti; Costa, Marina ChagasThe causes of the low desiccation tolerance and low longevity of coffee seeds have not yet been fully elucidated, and a full understanding of their complex physiology is of great interest. Among several alternatives, the loss of antioxidant capacity in seeds may be related to their rapid loss in quality during storage. The objective of this study was to determine the total antioxidant capacity of coffee harvested at different ripeness stages before and after the storage of seeds with different water contents and to relate antioxidant capacity to physiological quality. Seeds in the greenish-yellow or cherry stages, recently harvested or stored for nine months at 10 °C with 40, 30, 20 and 12% water content (wet basis - wb), were submitted to physiological and biochemical quality evaluations, and the Trolox equivalent antioxidant capacity (TEAC) was determined. The germination and root protrusion of coffee seeds from greenish-yellow and cherry fruits were not affected by drying, but seeds harvested at physiological maturity had greater vigor when the moisture content was lower. The quality of coffee seeds decreased during storage, and this decrease was greater in seeds stored with higher water contents. Coffee seeds in the greenish-yellow stage had a higher antioxidant capacity than those in the cherry stage when recently harvested, but there was a substantial reduction in this capacity during storage at both maturation stages. Coffee seed deterioration is related to a reduction in antioxidant capacity, and the isoenzymatic profiles of the antioxidant process are little affected by the seed maturation stage. The deterioration of coffee seeds during storage is related to a reduction in their total antioxidant capacity, regardless of their maturation stage, being more pronounced in the greenish-yellow stageItem Seedling production of Coffea arabica from different cultivars in a modified hydroponic system and nursery using different containers(Editora UFLA, 2021-11-22) Lima, Amador Eduardo de; Guimarães, Rubens José; Cunha, Samuel Henrique Braga da; Castro, Elisa de Melo; Carvalho, Alex Mendonça de; Faria, Mauro Magalhães LeiteThe development of modified hydroponic cultivation has aroused interest and its use has enabled advantages in several crops, but studies for coffee are still scarce. Thus, the objective of this research was to evaluate seedling production of three Coffea arabica cultivars (Mundo Novo IAC-376-4, Catuaí IAC-62 Amarelo and MGS Paraíso 2), in a modified hydroponic system, and to compare it with the nursery production system, using plastic polyethylene tubettes and bags. Coffee seedlings in the development phase with cotyledon leaves, were cultivated in both cultivation systems. At 90 days after the implementation of the experiment, the seedlings were analyzed for growth (height, stem diameter, total number, leaf area, root area, root and shoot dry matter weight), and physiological characteristics (chlorophyll content and stomatal conductance). For the statistical analysis, a completely randomized design (CRD) was used in a factorial scheme 3 (cultivars) x 2 (containers) x 2 (cultivation systems), with four replications of ten plants per plot. The innovative production system of coffee seedlings in modified hydroponics, in combination with the use of polyethylene bags, provided greater growth of coffee seedlings with better physiological characteristics. Among the cultivars tested, MGS Paraíso 2 stood out with higher seedling growth (number of leaves, stem diameter and root and shoot dry matter weight).