Sirvi Autor "Silva, N.V." järgi
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Kirje Agronomic and bromatological characteristics of Cassava cultivars(Estonian University of Life Sciences, 2025) Silveira, R.B.; Pires, A.J.V.; Dutra, I.C.; Nogueira, M.S.; Andrade, W.R.; Jesus, M.R.; Oliveira, G.R.S.; Oliveira, E.J.; Silva, N.V.; Santos, B.E.F.; Sousa, M.P.; Públio, P.P.P.The aim of this study was to evaluate the potential of the aerial part of cassava, analyzing its development and nutritional value, in addition to the production of biomass at different times and with different management. A randomized complete block design was used, with six cassava varieties (BRS Formosa, BRS Mulatinha, Eucalyptus, BRS White Pot, BRS Kiriris and BRS New Horizon) and five replicates, harvested six and twelve months after planting, with and without pruning. To evaluate the amount of biomass produced by the aerial part of cassava and the production of roots, a 6×2 factorial scheme in randomized complete blocks design was conducted. Six cassava varieties were tested, each with five replicates. The plants were harvested at two different times: with pruning (harvesting at six and twelve months after planting) and without pruning (single harvest at twelve months). There was an effect for the characteristics plant height, stem diameter, number of stems, number of leaves, lobe length, lobe width and petiole length, however when they were evaluated at twelve months, there was no effect, only for the characteristics lobe length and petiole length. It was found that there was an effect for dry matter, ether extract, hemicellulose and ADF. The BRS White Pot variety presented a higher concentration of non-fibrous carbohydrates. Differences were observed for neutral detergent fiber corrected for ash and protein and lignin. For the values of total digestible nutrients, the cultivars BRS White Pot, BRS New Horizon and BRS Formosa stood out in relation to the others. There was a difference in the protein fractionation of the different cassava cultivars for total nitrogen fraction, fraction A and fraction C when they were harvested six months after planting. However, when they were evaluated at twelve months, there was only an effect for fraction C. There was an effect for CT, fraction A+B1, fraction B2 and fraction C when they were evaluated six months after planting. However, when they were evaluated twelve months after planting there was no difference for total carbohydrates and fraction B2. The interaction was not significant between the different cultivars and pruning management for the production of green matter, dry matter, crude protein, total digestible nutrients of the aerial part and green matter and dry matter of the roots. In management without pruning, there was an increase in the variables PGMPA, PDMPA, PCPPA and PTDNPA. The cultivars BRS Mulatinha and BRS New Horizon are recommended as they present greater leaf retention and number of stems, providing greater biomass production when managed without pruning.Kirje Liquid fertilization and conventional fertilization on soil fertility and agronomic and morphophysiological characteristics of Brachiaria brizantha cv. Braúna grass(Estonian University of Life Sciences, 2025) Muricy, J.F.; Silva, F.F.; Dutra, G.C.; Neto, T.M.; Dutra, I.C.; Santos, C.J.; Silva, R.R.; Hermógenes, R.S.; Cerqueira, F.F.; Pires, A.J.V.; Silva, N.V.; Santos, B.E.F.The objective of this study was to evaluate the effect of liquid and conventional fertilization on soil fertility, assessed by regrowth, and on the morphophysiological characteristics of Brachiaria brizantha cv. Braúna. The experiment was conducted in a greenhouse at the State University of Southwest Bahia, in Itapetinga-BA, from December 2018 to April 2019. The experimental design adopted was completely randomized, with four replicates, totaling 24 experimental units, in a 2×3 factorial scheme, comprising two types of fertilization (liquid and conventional) and three regrowths, with cutting intervals of 21 days. The results revealed that conventional fertilization promoted an increase in the levels of calcium (Ca) and phosphorus (P) in the soil, which, in turn, positively impacted the sum of bases and base saturation, reaching values of 5.6 cmolc dm-3 and 54%, respectively, in the first regrowth. The dry mass production of the aerial part was influenced by both regrowth and the type of fertilization. A 27% reduction in dry mass production was observed from the first to the second regrowth, and a 16% reduction from the second to the third. On the other hand, conventional fertilization provided a 20% increase in dry mass production. The morphological variables of the plant were influenced by regrowth, with the exception of the leaf appearance rate (LAR), which did not present significant variations. A reduction in the other morphological variables was observed with each regrowth. Fertilization, in turn, influenced only the length of the flagellum leaf (LFL) and the total length of the tiller (TTL). The interaction between regrowth and fertilization was significant for leaf area, specific leaf area, leaf area index and leaf area ratio. The SPAD index, chlorophyll b and total chlorophyll contents were influenced by regrowth, with a progressive increase with each regrowth. Conventional fertilization promoted an increase in the SPAD index, with a value of 35.53, compared to 33.51 for liquid fertilization. The interaction between regrowth and fertilization was significant for the chlorophyll a:b ratio and carotenoids. The chlorophyll a:b ratio decreased with each regrowth. Conventional fertilization resulted in a 1.04% increase in crude protein content compared to liquid fertilization. Dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF) and ash contents were influenced by regrowth, with a progressive increase with each regrowth, except for ash, which showed a reduction. Regrowth demonstrated greater influence on the productive and morphophysiological characteristics of braúna grass. Conventional fertilization is recommended to promote improvements in soil fertility and increase the crude protein content of signal grass Brachiaria brizantha cv. Braúna.Kirje Productive and biochemical responses of Marandu grass under fertilization protocols(Estonian University of Life Sciences, 2025) Dutra, I.C.; Pires, A.J.V.; Jardim, R.R.; Silva, H.S.; Santos, B.E.F.; Silva, N.V.; Ribeiro, A.S.; Dutra, G.C.; Filho, C.A.A.O.; Publio, P.P.P.; Silva, A.P.G.; Nogueira, M.S.The aim of this study was to evaluate the effects of liming and chemical fertilization protocols, containing different combinations of nitrogen (N), phosphorus (P) and potassium (K), on the photosynthetic pigments, productive characteristics and carbohydrate concentration of Urochloa brizantha cv. Marandu. Five fertilization protocols were evaluated (PK fertilizer combination; NP fertilizer combination; NK fertilizer combination; NPK fertilizer combination; and without fertilizer - control), associated or not with soil correction via liming, in a completely randomized design, with four replicates. The experimental units consisted of plastic pots with a capacity of 12 liters, which were filled with 10 dm³ of sandy clay loam soil. Seeds of Urochloa brizantha cv. Marandu, with 80% cultural value were used. With the corrected soil, the NP protocol provided greater production of dry mass of residue (PMSRE), root volume, leaf area, leaf area index, total sugar content (AST) and starch in the root, compared to the other protocols. Without liming, the NP protocol provided greater production of aerial part dry mass (PMSPA), root volume, leaf aerial volume, leaf aerial index and AST content in leaves, roots and residue. The NPK protocol, with liming, was 73% higher in chlorophyll a content, 50% in carotenoid content, 90% in PMSPA, 78% in leaf area and 76.2% in leaf area index, compared to the soil without correction. The use of NP fertilization with liming is recommended as it provides positive responses on the photosynthetic pigments, productive characteristics and total sugar content of Marandu grass.Kirje The quality and fermentation of the total diet containing BRS capiaçu or sugarcane with or without urea(Estonian University of Life Sciences, 2025) Silva, N.V.; Pires, A.J.V.; Dutra, I.C.; Silva, H.S.; Santos, B.E.F.; Nogueira, M.S.; Cruz, N.T.; Silva, A.P.G.; Teixeira, L.S.; Oliveira, G.R.S.; Dutra, G.C.; Teixeira, L.S.The objective of this study was to evaluate total diet silages in PVC silos, containing BRS Capiaçu or sugarcane with or without urea. The experimental design was completely randomized with a 2x2 factorial arrangement with ten replicates, with one of the roughages (sugarcane or Capiaçu) being with or without urea (2% urea on a dry matter basis). No interaction was observed between the bulk and urea factors for the variables analyzed. Diets containing sugarcane presented greater gas losses and lower pH. In contrast, effluent losses and dry matter recovery were higher in diets containing BRS Capiaçu. Ammonia nitrogen levels were influenced by both the type of roughage and the addition of urea, being higher in diets with urea and those containing BRS Capiaçu. Diets with BRS Capiaçu also resulted in higher levels of ash, NDF, ADF, hemicellulose, cellulose, and lignin. The addition of urea, in turn, reduced lignin levels. The levels of ADIN and NDIN were higher in diets with BRS Capiaçu and lower in those with sugarcane, while urea reduced ADIN. For NFC, there was an effect of roughage and urea, with higher values observed in diets with sugarcane and with the addition of urea. The highest iNDF levels were found in diets with BRS Capiaçu and without urea. Protein fractionation showed that the addition of urea increased fraction A and reduced fractions B1+B2 and C. Fraction B3 was higher in diets with sugarcane. Fraction C showed higher levels with BRS Capiaçu and when urea was not added. Sugarcane resulted in higher levels of fractions A+B1 and lower levels of B2 and C, a pattern opposite to that observed with BRS Capiaçu. Similarly, urea increased fractions A+B1 and decreased fractions B2 and C. The addition of urea to the diets promoted changes in the carbohydrate and protein fractions, improving the composition. Regarding the roughage used, sugarcane presented better fermentation parameters when purchased from Capiaçu.