Fungos micorr?zicos arbusculares na cultura da mandioquinha-salsa

• Autor(a) principal: Martins, Carla Andreia da Cunha
• Data de Publicação: 2005
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFRRJ
• Texto Completo: https://tede.ufrrj.br/jspui/handle/jspui/3503
• topic: batata baroa; bact?rias diazotr?ficas; f?sforo; arracacha; diazotrophic bacteria; phosphorus; Agronomia

This study was accomplished in an area of Nova Friburgo municipality ? RJ State (site 1), in Embrapa Agrobiologia Experimental Station (site 2), and in the experimental area of Soils Department, UFRRJ (site 3), the sites 2 and 3 in Serop?dica municipality, Rio de Janeiro State (Brazil). The experimental design of the Nova Friburgo site was of randomized block with 4 repetitions and 9 NPK treatments (000, 010, 020, 100, 111, 120, 200, 210 and 222). The soil was a Nitossolo (Ultisol) and the variety used was ?Amarela de Caranda?? (AC). The four sampling periods were at 3, 5, 7 and 10 months after planting (MAP). The objective was to verify incidence of arbuscular micorrhizal fungi (AMF) in the Peruvian carrot culture. In Nova Friburgo-RJ site, the quantification of diazotrophic associative bacteria endophytic of Peruvian carrot plants was evaluated in 2004 through the Most Probable Number method. The objective was to verify the presence of diazotrophic bacteria in the varieties AC and ?Amarela de Senador Amaral? (ASA). In the site 2, the experiment installed was of the type split-splot blocky randomized design. The treatments were 6 types of substrate (plots): 1 (commercial substrate - CS); 2 (75% CS, 25% sand); 3 (70% organic compost - CO), 30% sand); 4 (27% loamy soil (LS), 27% CO, 46% sand); 5 (40% SL, 20% CO, 40% sand) and 6 (20% SL, 40% CO, 40% sand). The split-splot parcels were: Glomus clarum inoculation and control (without inoculation). The crop variety was the AC and it was collected at 20, 35 and 50 days after the planting. This study had as objective to select the best substrate media for seedling growth. In the site 3, it was installed an experiment with randomized blocks design and of split-splot type. The plots were constituted of two mixes of the AMF and the treatment control (without inoculation). The split-splot parcels were: 4 levels of phosphorus (15, 40, 100 and 240 mg P kg-1 of soil) and the control (without P). The variety used was the AC and the inoculation consisted of 200 spores in suspension per plant. The objective was to evaluate efficiency of AMF in the development and nutritional status of Peruvian carrot plants. The results showed that for the site 1, the largest colonization percentage occurred with 3 MAP and the number of spores was relatively high during all the sampling periods. It was verified the occurrence of 29 species of AMF, in six genera, in the different fertilizing treatments. The predominant specie was Glomus macrocarpum. In 2004 in the site 1, the two varieties AC and ASA hosted native diazotrophic bacteria. The observed genera were Azospirillum, Herbaspirillum and Burkholderia, and the Gluconacetobacter was not present. The best development of Peruvian carrot seedlings happened in the substrate with larger proportion of organic compost, site 2. The largest radicular specific area and length was verified in the control. Inoculation with AMF did not contribute with an increase of dry matter in any part of the plant (leaf+petiole, corms and root). In the third site, the largest nitrogen and phosphorus levels were obtained with the mix of species of the fungi collection. Native AMF showed to be less efficient for the plant growth. It was found that Peruvian carrot corms carry AMF that are efficient for the crop.