PRODUÇÃO DE MATÉRIA SECA E EVAPOTRANSPIRAÇÃO REAL DA AVEIA PRETA (Avena strigosa S.) EM SEIS NÍVEIS FREÁTICOS

PRODUÇÃO DE MATÉRIA SECA E EVAPOTRANSPIRAÇÃO REAL DA AVEIA PRETA (Avena strigosa S.) EM SEIS NÍVEIS FREÁTICOS Marcos Henrique Dias SilveiraAntonio Evaldo KlarDepartamento de Engenharia Rural – Faculdade de Ciências Agronômicas – UnespBotucatu – SP Cep: 18603-970Fone: (0xx14) 6802-7165 – [email protected] 1 RESUMO Para avaliar os efeitos de seis diferentes níveis freáticos na produção de matéria seca e na evapotranspiração real ou de cultura da aveia preta (Avena strigosa S.) foi conduzido um experimento em casa de vegetação, no Departamento de Engenharia Rural da FCA - Campus de Botucatu - UNESP. Foram semeadas 21 sementes de aveia por vaso, construído de anéis de PVC, com diâmetro nominal de 0,15m x 0,07m de comprimento e alturas totais variando entre 0,21m e 0,91m, de modo a simular os efeitos de níveis freáticos de 0,17m, 0,31m, 0,45m, 0,59m, 0,73m e 0,87m de profundidade. Após a emergência das plântulas procedeu-se ao desbaste, deixando-se 8 plantas por vaso, com 06 repetições (seis vasos) para cada nível freático, totalizando 36 vasos em delineamento inteiramente casualizado. Dados de evapotranspiração real foram coletados diariamente e computados semanalmente. As plantas foram cortadas rente ao solo ao final da 12.ª semana após a semeadura. Foram avaliadas as produções de matéria seca da parte aérea e do sistema radicular em cada nível freático. Os resultados mostraram maior produção de matéria seca para o nível freático mais superficial (0,17m), com queda gradativa à medida que o nível freático se aprofundava. A evapotranspiração da cultura mostrou a mesma tendência, variando entre 591,6 mm no tratamento com nível freático a 0,17m de profundidade e 215,4 mm para o de 0,87m de profundidade. UNITERMOS: evapotranspiração, níveis freáticos, aveia preta. SILVEIRA, M. H. D., KLAR, A. E. DRY MATTER PRODUCTION AND EVAPOTRANSPIRATION OF OAT ( Avena strigosa S.) UNDER SEVERAL TABLE LEVELS. 2 ABSTRACT The aim of this study was to evaluate the influence of six different water table levels on yield and evapotranspiration of oat (Avena strigosa S.) . 21 seeds were sowed per pot, which was built with PVC rings (0.15m nominal diameter x 0.07m lenght). 6 water table levels were used: 0.17; 0.31; 0.45; 0.59; 0.73; and 0.87 m measured from the soil surface replicated 6 times. The completely randomised design was used. After seedling emergency, 8 plants were maintained per pot. The evapotranspiration were daily measured from reservoirs connected to the pots. The plants were cut at the soil surface level after 12 weeks from the sowing.The results showed greater dry matter production at the most superficial water table level with progressive decrease with water level distance from the soil surface. The evapotranspiration showed the same tendency: the higher values occurred on the 0.17m water table (591.6 mm) until 0.87m water table (215.4 mm). KEYWORDS: water table, evapotranspiration, Avena strigosa S.

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Effects of irrigation frequency and transient waterlogging on the production of a perennial ryegrass - white clover pasture

Australian Journal of Experimental Agriculture ◽

10.1071/ea96057 ◽

1997 ◽

Vol 37 (2) ◽

pp. 165 ◽

Cited By ~ 12

Author(s):

J. S. Dunbabin ◽

I. H. Hume ◽

M. E. Ireson

Keyword(s):

Perennial Ryegrass ◽

White Clover ◽

Dry Matter ◽

Soil Surface ◽

Dry Matter Production ◽

Irrigation Frequency ◽

Pasture Production ◽

Absolute Increase ◽

Irrigation Interval ◽

Matter Production

Summary. Perennial ryegrass–white clover swards were irrigated for 3 years every 50, 80 and 120 mm of crop evapotranspiration minus rainfall (ETc–R) and water ponded on the soil surface for either 4, 12 or 24 h at each irrigation. Pasture production and clover content were highly seasonal, peaking in spring and autumn. Frequent irrigation increased dry matter production by an average of 56%. When irrigating at 50 mm ETc–R, dry matter production was decreased by ponding water on plots, 17% for 12 h ponding and 14% if ponded for 24 h. However, when irrigating at an interval of 80 mm ETc–R ponding increased dry matter production by 7% for 12 h ponding and by 25% for 24 h ponding. Ponding also increased production at an irrigation interval of 120 mm ETc–R by 25% for 12 h ponding but only by 2.4% for 24 h ponding. While these increases in dry matter production are large in relative terms the absolute increase in production is small. More water infiltrated per irrigation at longer irrigation intervals, and at longer ponding times. Frequently irrigated, rapidly drained swards used irrigation water most efficiently. The small gain in dry matter production achieved by prolonging ponding at longer irrigation intervals is an inefficient use of water and likely to recharge regional groundwater systems. Oxygen diffusion rate measurements suggested that ponding for as short as 4 h was likely to cause waterlogging stresses and that these stresses were higher when irrigating frequently. The relative increase in waterlogging stress by extending the period of ponding from 4 to 24 h was small.

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Response of nine soybean lines to soil moisture conditions close to saturation

Australian Journal of Experimental Agriculture ◽

10.1071/ea9800339 ◽

1980 ◽

Vol 20 (104) ◽

pp. 339 ◽

Cited By ~ 17

Author(s):

MN Hunter ◽

PLMde Jabrun ◽

DE Byth

Keyword(s):

Water Table ◽

Dry Matter ◽

Inorganic Nitrogen ◽

Irrigation Treatment ◽

Soil Surface ◽

Dry Weight ◽

Node Number ◽

Matter Production ◽

High Yields ◽

Moisture Conditions

The effects of two constant water table treatments, maintained at 3 and 15 cm below the soil surface (CWT 3 and CWT 15, respectively), were compared with the effect of overhead irrigation (OHI) on dry matter production of nine soybean (Glycine max) lines, grown for 36 days in beds of soil in the glasshouse. The lines represented a range of maturity groups. Water for each irrigation treatment was supplied with, or without, dissolved inorganic nitrogen (100 ppm N), on a split plot basis. CWT 15 plants accumulated 37% more dry matter, and 35 times more nodule dry matter, than did OH1 plants. CWT 3 plants became very chlorotic within a week of imposing the water table, but recovered to produce only 18% less dry matter than the OHI plants. CWT 3 plants accumulated the greatest amount of nodule dry matter, and this fraction accounted for 5% of total plant dry weight in some lines. Plants in both of the water table regimes were taller than the OHI plants, even for lines that flowered in 21 days, and this effect reduced the cultural disadvantage of short stature normally noted in early flowering lines. Nitrogen application marginally increased shoot proportion, plant height and node number, but decreased nodule mass in CWT 15 and OHI plants. The study indicated that soybeans can respond well to permanent water tables maintained close to the soil surface, and attain rapid early growth independent of applied nitrogen. Projections suggest that high yields of seed are feasible in 80-85 day soybean crops growing on a controlled water table system. This system also may promote other operational efficiencies related to a shortened cropping cycle, simplified water management, and weed control.

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Evaluation of perennial herbaceous legumes with different phosphorus sources and levels in a Brazilian Ultisol

Renewable Agriculture and Food Systems ◽

10.1079/raf200492 ◽

2005 ◽

Vol 20 (1) ◽

pp. 56-62 ◽

Cited By ~ 5

Author(s):

J.A.A. Espindola ◽

J.G.M. Guerra ◽

D.L. Almeida ◽

M.G. Teixeira ◽

S. Urquiaga

Keyword(s):

Cover Crops ◽

Dry Matter ◽

Soil Layer ◽

Soil Surface ◽

Dry Matter Production ◽

Organic C ◽

Herbaceous Legumes ◽

Matter Production ◽

Phosphorus Sources ◽

Phosphate Fertilization

AbstractThis study was carried out under field conditions with the aim of evaluating the period of time necessary for soil cover, dry matter production and accumulation of nutrients by perennial herbaceous legumes with different phosphorus sources at different levels. Four legumes were evaluated: calopo (Calopogonium mucunoides Desv.), forage groundnut (Arachis pintoi Krap. & Greg.), siratro (Macroptilium atropurpureum (OC.) Urb.) and tropical kudzu (Pueraria phaseoloides (Roxb.) Benth.). Each of these species received different phosphorus (P) sources and levels: no phosphate fertilization; 44 and 88 kg of P ha−1 applied as rock phosphate; and 44 kg of P ha−1 as triple superphosphate. Calopo, siratro and tropical kudzu completely covered the soil surface 129 days before forage groundnut. Phosphate fertilization did not increase the dry matter production of any species. The legumes forage groundnut, siratro and tropical kudzu showed desirable characteristics that promote their use as cover crops, such as high dry matter production and shoot accumulation of nitrogen (N) and potassium (K). Forage groundnut had the highest proportion of N derived from the atmosphere at the end of the rainy season, while there were no significant differences between the legumes at the end of the dry season. There was an elevation of soil pH and calcium+magnesium (Ca+Mg) contents, associated with a reduction of aluminum (Al) content, in the surface soil layer (0–5 cm) for siratro in relation to groundnut and tropical kudzu. Tropical kudzu promoted higher soil organic C contents when compared to groundnut.

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INFLUÊNCIA DA DENSIDADE DE PLANTAS, CORTES E DOSES DE NITROGÊNIO NA PRODUÇÃO DE CAPIM-PIATÃ

Nativa ◽

10.31413/nativa.v8i4.8515 ◽

2020 ◽

Vol 8 (4) ◽

pp. 523-532

Author(s):

Adriano Catossi Tinos ◽

Giuliani do Prado ◽

Beatriz Furlan Fonseca ◽

Jhésmila Ingridy Bueno ◽

Rafael Rech Bruscagin

Keyword(s):

Aerial Part ◽

Dry Matter ◽

Plant Density ◽

Block Design ◽

Soil Surface ◽

Dry Matter Production ◽

Forage Production ◽

Nitrogen Levels ◽

Matter Production ◽

Randomized Complete Block Design

O Brasil apresenta numeroso rebanho bovino e as pastagens proporcionam a maneira mais prática e econômica de fornecer forragem ao rebanho. O trabalho, conduzido na Universidade Estadual de Maringá, em Cidade Gaúcha, Paraná, objetivou avaliar o efeito da densidade de plantas e de doses de nitrogênio na produção de forragem de Brachiariabrizantha cv. Piatã. O experimento foi implantado em delineamento experimental em blocos ao acaso em esquema fatorial 4x4x10, com três repetições. Foram avaliados: i) doses de nitrogênio (0, 17, 33 e 50 kg ha-1 corte-1),aplicadas em cobertura após cada corte do pasto; ii) densidade de plantas (10, 20, 30 e 40 plantas m-2) e; iii) 10 ciclos de cortes das pastagens, realizados no decorrer do experimento. As produções de matéria fresca e seca da parte aérea da pastagem foram avaliadas. Os ciclos de corte e as doses de nitrogênio influenciaram na produção de massa fresca e seca. As maiores produções de massa fresca e seca foram obtidas na densidade de 10 plantas m-2 e, as menores, na densidade de 40 plantas m-2. O aumento da dose de nitrogênio até 50 kg N ha-1 corte-1 proporcionou incremento na produção de massa fresca e seca de pastagem de Piatã.Palavras chave: ciclo de corte; forragem; massa seca. INFLUENCE OF PLANT DENSITY AND NITROGEN DOSES ON CAPIM-PIATÃ PRODUCTION ABSTRACT: Brazil has a large cattle herd, and pastures have offered the most practical and economical way of providing them forage. This work was carried out at the UniversidadeEstadual de Maringá, in CidadeGaúcha city, Paraná state, and it aimed to evaluate the effect of plant density and nitrogen levels on forage production of Brachiariabrizantha cv. Piatã.The experiment was set out in a randomized complete block design in a 4x4x10 factorial scheme, with three replications. The evaluated factors were: i) nitrogen doses (0, 17, 33 e 50 kg ha-1 cut-1), applied on the soil surface after each cutting cycle; ii) plant density (10, 20, 30 e 40 plants m-2) and; iii) 10 pasture cutting cycles which were performed over the experiment. Fresh and dry matter productions of the pasture aerial part were evaluated. The factors cutting cycles and nitrogen levels had influenced on fresh and dry matter production of pasture. The highest yields of fresh and dry matter production were obtained at a plant density of 10 plants m-2 and the smallest yields for the plant density of 40 plants m-2. Increasing the nitrogen dose by 50 kg N ha-1 cut-1 provided an increase in the fresh and dry matter production of Brachiariabrizantha cv. Piatã.Key words: cuttingcycle; forage; dry matter.

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