Publicações Científicas
URI permanente desta seção${dspace.url}/handle/123456789/3352
Navegar
4 resultados
Resultados da Pesquisa
Item Arbuscular mycorrhizal fungal communities associated with coffee intercropped with grevillea(Sociedade Botânica do Brasil, 2024-12-02) Santos, Roberta de Souza; Miguel, Divino Levi; Freitas, Leandro Martins de; Assis, Fábia Giovana do Val de; Teixeira, Valber Dias; Kemmelmeier, Karl; Stürmer, Sidney Luiz; Leal, Patrícia LopesArbuscular mycorrhizal fungi (AMF) communities in coffee-cultivated areas in the northeastern region of Brazil have been insufficiently studied when compared to other Brazilian regions. This study determined AMF occurrence and richness in coffee-cultivated soils under different management systems in the State of Bahia, Brazil, and in soils from surrounding areas with pasture and native forest (control areas). Physicochemical soil characteristics in the different study areas were also evaluated. A total of 43 AMF spore morphotypes in 14 genera belonging to six families were recovered from soil samples from all study areas: Glomeraceae (35%), Acaulosporaceae (35%), Gigasporaceae (21%), Ambisporaceae (5%), Archaeosporaceae (2%) and Diversisporaceae (2%). Rhizophagus fasciculatus, Acaulospora mellea and Glomus sp. 1 were the most frequent fungi found in all areas. In the coffee-cultivated areas, 12 genera were identified, two of which (Dominikia and Fuscutata) had not yet been reported in association with coffee plants in Brazil. We concluded that soil physicochemical properties and AMF occurrence can distinguish study areas based on land use. The different coffee management systems did not influence AMF species richness, but the occurrence was influenced by both management and soil factors.Item Occurrence of arbuscular mycorrhizal fungi in leaf litter and roots of shaded coffee plantations under organic and conventional management(Sociedade Brasileira de Ciência do Solo, 2021) Díaz-Ariza, Lucía Ana; Rivera, Emma Lucía; Sánchez, NataliaEvidence of arbuscular mycorrhizal fungal colonization of mat litter in various ecosystems plus previous reports of external mycelium of those fungi and mycorrhizal roots in litter from coffee plants and shade trees on coffee plantations suggest that they have a relationship with closed direct nutrient cycling between organic matter and living roots. This relationship was first proposed more than 50 years ago. Mycorrhizal symbiosis in tropical crops is affected by agricultural management practices. This study aimed to assess the occurrence of arbuscular mycorrhizal fungi in leaf litter from three shaded Colombian coffee agroecosystems under organic and conventional management. One is managed chemically, one organically, and one with a combined use of organic and chemical inputs. Leaf litter and roots were collected from the three coffee plots at three decomposition stages. Each plot represented a distinct fertilization and tree dominance pattern different from the other two plots. Arbuscular mycorrhizal fungi were found in decomposing leaves. The chemically managed plot showed statistical differences (p<0.05) with respect to the other plots, it had the greatest amounts of arbuscular mycorrhizal fungal root colonization (48.76–70.51 %), litter colonization (36.2–69.91 %), external mycelium length (28.66–48.33 m g-1), and spore number (451.27–681.2 spores in 20 g of dry soil). In contrast, conditions on the combined management coffee plot results in smaller means of the variables evaluated. Arbuscular mycorrhizal fungal root colonization and nitrogen content of leaf litter varied among the decomposition stages (p<0.05). Litter quality of different tree species may have influenced colonization of plant matter within each plot. We found evidence of typical structures of arbuscular mycorrhizal fungi within and among decomposing leaf litter and roots growing into the mat litter in tropical agroecosystems. This supports the thought that these fungi have a role in carbon and nutrient recycling, which are influenced by agricultural management practices and plant population composition.Item Evaluation of Conilon coffee productivity intercropped with Ambarella (Spondias dulcis Parkinson)(Editora UFLA, 2020) Sales, Eduardo Ferreira; Baldi, Adriana; Alvez, Juan P.The State of Espirito Santo (Brazil) has 9.4 % of its area cultivated in full sun, monocrop coffee. Coffee has a great importance for the State and a dependence on just one product can make farmers vulnerable to price fluctuations. Integrating coffee (Coffea canephora Pierre ex Froehner) intercropped with Ambarella (Spondias dulcis Parkinson) offers environmental benefits and an extra financial combination through the commercialization of Ambarella fruits. The goal of this study was to verify the effects of the distance and orientation (East-West versus North-South) between Ambarella on coffee crop yield. We assessed two different coffee crops spaced (3 x 1.5) m. Both were intercropped with Ambarella spaced (15 x 7.5) m. The average coffee productivity varied from (2,177 to 7,346) kg plant-1. The lowest productivity was measured in the North-South orientation, during 2016, and the highest in the East-West orientation during 2017. Our findings also indicate that regardless of planting distance, Ambarella did not significantly affected coffee productivity demonstrating that it can be a promising fruit tree to intercrop with Conilon coffee.Item Modifications on leaf anatomy of Coffea arabica caused by shade of pigeonpea (Cajanus cajan)(Instituto de Tecnologia do Paraná - Tecpar, 2004-11) Morais, Heverly; Medri, Moacyr Eurípedes; Marur, Celso Jamil; Caramori, Paulo Henrique; Ribeiro, Ana Maria de Arruda; Gomes, José CarlosModifications on leaf anatomy in Coffea arabica shaded with pigeonpea (Cajanus cajan), compared to cultivation under full sun, were assessed. The leaves fully exposed to sunlight presented thicker cuticles and cellular walls, narrower epidermis cells, palisade parenchyma with longer cells, thicker lacunar parenchyma, fewer intercellular spaces and a larger stomata number. Leaves under dense shade presented a narrower cuticle and cellular wall; a mesophyll with smaller volume, but with larger intercellular spaces; and epidermis with thicker cells and a smaller stomata amount, surrounded by subsidiary cells of smaller dimensions. Plants grown under full sunlight presented higher values of net photosynthesis. The results evidenced that the species C. arabica has a wide range of phenotypic adaptation to changes in the radiation intensity.