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Item Bioaugmentation as an associated technology for bioremediation of soil contaminated with sulfentrazone(Ecological Indicators, 2019-04) Melo, Christiane Augusta Diniz; Passos, Ana Beatriz Rocha de Jesus; Madalão, João Carlos; Silva, Daniel Valadão; Massenssini, André Marcos; Silva, Antônio Alberto da; Costa, Maurício Dutra; Souza, Matheus de FreitasThe association between remediation plants and bioenhancement with a bacterial consortium may improve the efficiency and accelerate the decontamination process of soils contaminated with herbicides. The objective of this work was to evaluate the potential for bioremediation of soils contaminated with sulfentrazone by using a previously selected bacterial consortium, namely, phytoremediator plants, and their combination. The treatments consisted of a single crop of Canavalia ensiformis, a single crop of Helianthus annuus, both species in mixed cultivation, tilled soil in association with the presence or absence of inoculation with a bacterial consortium and different bioremediation periods (25, 45, 65 and 85 days after thinning). At the end of each season, a bioassay was performed with the bioindicator species Sorghum bicolor, and the sulfentrazone residues were quantified in soil by high-performance liquid chromatography. The Helianthus annuus single crop and the mixed cultivation reduced by 64% the half-life of sulfentrazone in comparison to soil cultivated with C. ensiformis without inoculation and by 43% compared to the treatments composed of untilled soil and a single crop of C. ensiformis in the presence of inoculation, respectively. The mixed cultivation of C. ensiformis and H. annuus and the single crop of H. annuus, regardless of soil inoculation with the bacterial consortium, are the most efficient techniques of bioremediation of sulfentrazone in soil. Single-crop or mixed cultivation of these species on day 85 after thinning provides considerable reductions in the concentration of sulfentrazone in the soil; however, that period is not sufficient to allow the growth of the indicator plant without the occurrence of toxicity.Item Critical yield components and key loss factors of tropical cucumber crops(Crop Protection, 2006-10) Bacci, Leandro; Picanço, Marcelo Coutinho; Gonring, Alfredo Henrique Rocha; Guedes, Raul Narciso; Crespo, André Luiz BarretoThe critical components and the key factors of yield losses in autumn–winter and spring–summer cucumber crops were determined and quantified in Viçosa county, State of Minas Gerais, Brazil, in areas cultivated with gynoecium hybrids of the groups Aodai (Sprint 440 II) and “Caipira” (Vlasstar). The data were used to build crop life tables. The overall losses in the autumn–winter and spring–summer cultivations were of 53.5 and 66.6 ton ha−1, representing 76.3% and 59.2% of the overall crop yield potential. A critical component of yield loss was flower abortion in both cultivation periods. Fruit loss in the autumn–winter cultivation period was due to deficient pollination and production of non-marketable fruit size, and fruit damage caused by Diaphania spp. (Lepidoptera: Pyralidae), factors that also affected losses in the spring–summer cultivation period, followed by the physiological disturbance caused by nitrogen deficiency.Item Ecophysiological traits of the macaw palm: A contribution towards the domestication of a novel oil crop Author links open overlay panel(Industrial Crops and Products, 2013-01) Pires, Thiago Pereira; Souza, Elma dos Santos; Kuki, Kacilda Naomi; Motoike, Sérgio YoshimitsuAcrocomia aculeata, or macaw palm, is a highly productive oleaginous palm tree with the potential to be a new oil crop. Plant productivity is influenced by the exchange of gases between the leaf and the atmosphere. The assimilation of CO2 is dependent on both environmental factors and the intrinsic characteristics of the leaf, such as age, position in the canopy, and nutrient and pigment content. This study was conducted to characterize some ecophysiological aspects of macaw palm cultivated under field conditions. Foliar content and gas exchange parameters were analyzed in relation to diel variation, light intensity, and the position within the canopy and rachis. The evolution of photosynthesis and related variables during the daytime followed the standard patterns for most species with C3 metabolism, reaching peak levels during the morning hours. The light curve response also displayed a C3 pattern; however, this species demonstrated a high photosynthetic capacity with a maximum net photosynthesis and apparent quantum efficiency of approximately 23 μmol m−2 s−1 and 0.07 mol/mol, respectively. Gas exchange parameters of the fronds along the canopy varied according to the leaf position and the leaflet's insertion location within the rachis. Overall values indicate that the second and third leaves and the leaflets in the middle of the rachis have the best physiological capacity. Foliar pigment and mineral content were relatively stable among the leaves, which is a pre-requirement for long lasting leaves.Item Response of tomato (Solanum L. section Lycopersicon Mill.) germplasm to begomovirus inoculation under controlled and field conditions(Genetic Resources and Crop Evolution, 2014-02) Aguilera, Jorge González; Hurtado, Francisco Dueñas; Almeida, Victor de Souza; Tavares, Sheila S.; Nick, Carlos; Soares, Marcelo Oliveira; Xavier, Cesar A. Diniz; Gil, Martha Alvarez; Zerbini, Francisco Murilo; Silva, Derly J. Henriques da; Freitas, Renata Dias de; Ramos Sobrinho, RobertoNinety-five tomato accessions belonging to the Vegetable Crops Germplasm Bank of the Federal University of Viçosa (BGH-UFV) were evaluated in a protected environment (biolistic inoculation under greenhouse conditions) and in the field (natural infection) for resistance to bipartite begomoviruses present in Brazil. Plants were assessed by the visual evaluation of symptoms, and viral infection was confirmed by non-radioactive molecular hybridization. Univariate statistical analyses and correlations were made between the traits. High and significant correlations were found between the percentages of visual symptoms and of viral replication, with values of 0.67 in the protected environment and 0.60 in the field. We concluded that under the protected environment, the accessions BGH-2144, BGH-2150, BGH-6878 and BGH-6881 displayed resistance to infection. Under field conditions with natural infection, the best results were obtained for the accessions BGH-2080 and BGH-6881. Only the BGH-6881 (Solanum peruvianum L.) accession excelled in both conditions; this resistance was attributed to the presence of the Ty-2 and Ty-3 resistance gene alleles in heterozygosity. In general, all of the accessions selected in both experimental conditions can serve as sources for the development of cultivars tolerant or resistant to the bipartite begomoviruses present in Brazil.