Plantas De Cobertura Sobre Atributos Agronômicos Do Milho Na Região Sudoeste Da Amazônia

Abstract

RESUMO -O sistema plantio direto é uma estratégia sustentável de produção que preconiza a manutenção da cobertura vegetal como prática conservacionista do solo. Objetivou-se avaliar o efeito de plantas de cobertura sobre atributos fisiológicos e agronômicos do milho na região sudoeste da Amazônia. Foram avaliadas 15 estratégias de sucessões de culturas com o milho e a influência sobre o rendimento de biomassa, de grãos, altura de plantas e inserção da espiga, índice de espiga, massa de 100 grãos, teor foliar de nitrogênio e clorofilas total, a e b em plantas de milho.Observou-se efeito das plantas de cobertura sobre o rendimento de grãos, de biomassa fresca e seca, na massa de grãos e nos teores de clorofila. Os efeitos sobre os teores de clorofila foram mais pronunciados na clorofila b e nos estádios fenológicos finais da cultura. O feijão-de-porco promoveu as maiores produtividades de grãos (7.539,3 kg ha -1 ) e potencial de silagem (16,2 Mg ha -1 de biomassa seca). A adequada escolha das espécies que compõe um sistema de plantio direto é preponderante para o apropriado desempenho agronômico do milho na região sudoeste da Amazônia. Palavras-chave:Zea mays, intensificação ecológica, sustentabilidade, integração lavoura-pecuária, plantio direto. CROPPING SYSTEMS ON THE PERFORMANCE OF CORN PLANTS IN THE SOUTHWESTERN AMAZONABSTRACT-A sustainable strategy for agricultural systems is the use of cover crops in no-tillage systems, as a conservationist soil practice. This paper aimed to evaluate the short-term effects of different cover crops on some physiological and agronomic attributes of corn crop in the Southwestern Amazon region. The effects of 15 cover plants on the biomass and grains yield, plant height, ear insertion height, ear index, mass of 100 grains, leaf nitrogen content and a, b and total chlorophyll levels of corn plants were evaluated. A randomized complete block design was used with four replications. Grain yield, fresh and dry biomass yield, mass of 100 grains and chlorophyll content were affected by some cover crops. Jack bean promoted the highest grain yield (7,539.3 kg ha -1 ) and biomass yield (16.2 Mg ha -1 dry matter) among the options assessed. Cover crops provided different levels of total, a and b chlorophyll levels, on the corn plants. Some cover crops presented the potential to improve the agronomic performance of the succeeding corn crop in the Southwestern Amazon region. The proper agronomic performance of corn in a no-till system depends on the adequate choice of cover plants to compose the system. Sorgo, v.15, n.3, p. 531-542, 2016 RESUMO -O sistema plantio direto é uma estratégia sustentável de produção que preconiza a manutenção da cobertura vegetal como prática conservacionista do solo. Objetivou-se avaliar o efeito de plantas de cobertura sobre atributos fisiológicos e agronômicos do milho na região sudoeste da Amazônia. Foram avaliadas 15 estratégias de sucessões de culturas com o milho e a influência sobre o rendimento de biomassa, de grãos, altura de plantas e inserção da e...

Plot size and number of replications in Sudan grass

“…In those same six environments, the CG Farrapo cultivar had a fresh weight of 84.341 Mg ha -1 , a dry weight of 15.776 Mg ha -1 and grain yield of 3.866 Mg ha -1 (Arenhardt et al, 2016). Fresh and dry weights in Sudan grass (in the BRS Estribo cultivar) of 32.00 and 11.00 Mg ha -1 respectively, were obtained in the study by Aker et al (2016).…”

Effect of cover crops on physico-chemical attributes of soil in a short-term experiment in the southwestern Amazon region

“…The replacement cost of this nutrient via application of urea, was calculated by taking into account the composition of the nitrogen fertilizer as 45% of N and having a purchase cost of US$654.55 per ton in the local market (Banco Da Amazônia, 2014). The corn crop was sown in December 2014, using a single-cross hybrid RB 9308 YG VTPRO through a no-till seeder with a 0.90 m space between rows to achieve a final plant density of 70,000 plants ha -1 (Aker et al, 2016). After harvesting of all cover crops, soil samples in the layers 0 to 2.5; 2.5 to 5; 5 to 10 and 10 to 20 cm depth were collected at five separate locations per plot, forming a composite sample representative of each depth in each succession system (cover crops and fallow).…”

“…Soil mineralization and the loss of fertility, particularly organic matter, is high due to high temperatures together with high rainfall, that are experienced especially when tilling soil (Schlindwein et al, 2014). The use of a no-tillage system has proven to be an effective strategy to increase productivity and maintain sustainability of agroecosystem, this not only conditions the soil, thereby improving the supply of nutrients and water to plants (Mahama et al, 2016), but also provides benefits in terms of the physiology of plants such as increased grain yield (Carvalho et al, 2015;Aker et al, 2016).…”

Influence of Integrated Weed Management and Tillage Methods on Soil Physical and Chemical Properties in Maize Production

“…No or minimum tillage is a sustainability strategy for enhancing soil, water and crop performance [17,18]. Cover crop used is key determinant of success in no/minimum tillage system as it keeps the soil surface covered, recycle nutrients, making such available through gradual decomposition of organic residue.…”