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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Arbuscular mycorrhizal fungi community in coffee agroforestry, consortium and monoculture systems(Academia Brasileira de Ciências, 2022-06-27) Barros, Welluma T.; Barreto-Garcia, Patrícia A. B.; Saggin Júnior, Orivaldo José; Scoriza, Rafael N.; Silva, Maicon S. daUnderstanding the effects of different production systems on arbuscular mycorrhizal fungi (AMF) can help to interpret interactions between their components and to define management strategies. As a result, our study was conducted on soils under three coffee production systems (one homogeneous and two heterogeneous) and in a native forest located in the Bahia state, Brazil. This study aimed to answer the following questions: 1) Does the organization and management of the coffee production system affect the occurrence and diversity of AMF?; and 2) Is the seasonality effect similar between systems? To do so, soil samples (0-10 cm depth) were collected at two times of the year (rainy and dry). Number of spores (NS) and average richness did not show differences between the systems, only between seasons. There was a reduction in NS in the dry season (1.4 and 2.7 spores g-1 soil) in relation to the rainy season (3.8 to 12.5 spores g-1 soil). The influence of coffee production systems was observed in the presence and absence of some AMF species. The AMF community was shown to be related to the plant species composition of the system, which was reflected in the dissimilarity of heterogeneous systems in relation to the coffee monoculture system.Item Seed bank from soil of coffee plantations associated with grevillea trees(Sociedade Brasileira da Ciência das Plantas Daninhas, 2008-10) Santos, M.A.F.; Matsmoto, S.N.; Cesár, F.R.C.F.; Bonfim, J.A.; Araujo, G.S.; Viana, A.E.S.This study aimed to study the composition and dynamics of seed bank from soil of coffee plantations associated with grevilea trees in the experimental fields of the Southwest Bahia State University, on Vitória da Conquista campus. The experiments were carried out from September 2006 to May 2007. The coffee trees (Coffea arabica) were sown at three x one m spacing, associated with grevillea trees (Grevillea robusta) and maintained at densities of 277, 139, 123, 69, 62 and 31 plants ha-1 , under direct sunlight. One hundred grams of soil were taken from each treatment with four repetitions and later identified and counted with a 10x magnifying glass. To determine seedling emergence, four soil samples of 1000 g were collected from each experimental field and transported to the greenhouse. Seedling emergence was observed by counts after 15, 30 and 45 days. The experimental design was randomized blocks of seven treatments (soil from different tree densities) and four replicates; the experimental unit consisted of a plastic tray (0, 30 x 0.22 x 0.06 m) containing 1.000 g of soil. The variables utilized to characterize the bank and its dynamics were: relative frequency, relative density, relative abundance, importance index and species diversity (Shannon-Weaver index).Increased number of monocotyledon seeds and sprouts were verified in the treatments maintained under full sunlight.Item Diversidade e freqüência de plantas daninhas em associações entre cafeeiros e grevileas(Editora UFLA, 2006-07) Silva, Shirley de Oliveira; Matsumoto, Sylvana Naomi; Bebé, Felizarda Viana; São José, Alcebíades RebouçasEm Vitória da Conquista, Bahia, a arborização foi introduzida com o objetivo de reduzir os danos promovidos pela velocidade dos ventos incidentes nos cafezais. Entretanto, muitos outros efeitos como a redução da variação da temperatura do ar e da incidência da radiação solar, a manutenção da umidade e elevação da matéria orgânica do solo também foram observados. Tais alterações afetam a população de plantas de café, assim como o comportamento de outros componentes bióticos desse agroecossistema.. O presente trabalho foi realizado com o intuito de investigar a relação entre os cafezais (Coffea arabica L.) arborizados com diferentes densidades de grevíleas (Grevillea robusta A. Cunn) e a diversidade e freqüência de plantas daninhas infestantes. O experimento foi composto por seis campos de observação definidos por diferentes espaçamentos de grevíleas nos cafezais arborizados (T1: 6 X 6 m, T2: 6 X 12 m, T3: 12 X 9 m, T4: 9 X 9 m, T5: 9 X 18 m, T6:18 X 18 m) e um campo a pleno sol (T7). Os cafeeiros foram dispostos no espaçamento de três metros nas entrelinhas e um metro entre plantas, na linha. Foram identificadas 21 espécies de plantas daninhas, cinco espécies monocotiledôneas e 16 espécies dicotiledôneas. Os maiores índices de diversidade de plantas daninhas foram verificados nos campos com maiores números de árvores de grevíleas. A arborização nos cafezais influenciou a densidade, freqüência e a diversidade de espécies de plantas daninhas quando comparado com cafezais mantidos a pleno sol.