Produção de feijão-caupi sob efeito de veranico nos sistemas de plantio direto e convencional

Abstract

ResumoO objetivo do presente trabalho foi avaliar o efeito de diferentes períodos de deficiência hídrica, nos sistemas de plantio direto e convencional, sobre os componentes de produção e rendimento de grãos de feijão-caupi, na Região de Mossoró-RN. Para isso, foi realizado um experimento utilizando-se dois sistemas de plantio (convencional e direto) submetidos a períodos de suspensão da irrigação (2; 6; 10; 14; 18 e 22 dias), iniciados por ocasião do florescimento (34 dias após a semeadura). A colheita foi realizada aos 70 dias após a semeadura, sendo colhida uma das linhas da área útil, correspondendo a uma linha de 4 m por subparcela, as variáveis avaliadas foram: comprimento de vagens (CV); número de grãos por vagem (NGV); número de vagens por planta (NVP); peso de cem grãos em gramas (PCG) e rendimento de grãos (kg ha -1 ). O sistema de plantio direto é mais produtivo do que o convencional sob irrigação e em condição de estresse. Os períodos de veranico influenciaram negativamente o rendimento de grãos e todos os componentes de produção estudados, com exceção do peso de cem grãos. Entre os sistemas estudados, o plantio direto foi o que proporcionou maiores valores para os componentes de produção, exceto peso de cem grãos. Palavras-chave: Vigna unguiculata (L.) Walp, cobertura do solo, estresse hídrico, rendimento de grãos, componentes de produção AbstractThe objective of this study was to evaluate the effect of different periods of water shortage in notillage and conventional crop systems on cowpea yield components and grain yield in the Mossoró-RN region. For this, an experiment was conducted using two tillage systems (conventional and no-tillage) subjected to periods of irrigation suspension (2; 6; 10; 14; 18 end 22 days), started at flowering (34 days after sowing). Plants were harvested 70 days after sowing, and the studied variables were: Pods length (CV), number of grains per pod (NGV), number of pods per plant (NPP), the hundred grains weight (PCG) and grain yield (kg ha -1 ). The no-tillage system is more productive than the conventional under both irrigation and water stress treatments. The water stress length affected grain yield and all yield components studied in a negative way, except for the hundred grains weight. Among the systems studied, the no-tillage provides higher values for the yield components, except the hundred grains weight.

Competition between cowpea and weeds for water: Effect on plants growth

“…Some of its genotypes have tolerance to the temporary water deficit of the soil, characteristic that makes the crop one of the preferred for cultivation in periods of lower precipitation, mainly in the North, Northeast and Midwest regions of Brazil (Nascimento et al, 2011;Dutra et al, 2015). In these regions, droughts (summer) are common in the rainy season and, consequently, problems caused by water deficit, such as reduced growth and productivity, are common (Sousa et al, 2009;Freitas et al, 2014;Souza et al, 2017).…”

Agronomic Performance of Cowpea Cultivars Depending on Sowing Seasons in the Cerrado Biome

“…Therefore, air temperature, precipitation, and especially the rainfall distribution, are essential factors to the determination of the cowpea sowing season (CARDOSO; LIMA, 2005;SANTOS et al, 2009;FREITAS et al, 2013;MATOSO, 2014).…”

Physiological Responses of Cowpea Under Water Stress and Rewatering in No-Tillage and Conventional Tillage Systems

“…With the resumption of irrigation, the plants were in full reproductive stage, dedicating their resources to the formation of reproductive structures (flowers, flower stalks and pods). During this occasion, there is a stoppage of the actions toward photoassimilates to form new leaves (source), and the reproductive structures become the main sink (FREITAS et al, 2014). Thus, at this time, there is an increased percentage of dry weight of fruits in relation to other organs (FONTES; DIAS; SILVA, 2005;LOPES et al, 2011;FREITAS et al, 2014).…”

“…A significant increase of LA and TDM in the no-tillage system between 29 and 36 days was observed, compared to those of conventional tillage. Even though there is a reduction in the growth rate of LA after that period in both planting systems, which is associated with the transition to the reproductive stage (FREITAS et al, 2014), it is clear that the TDM, both in the conventional and no-tillage system, maintained the growth trend at 57 days. Since there was no change in the photosynthetic rates among the planting systems (Table 1), it is understood that the increase in TDM is due to higher LA accumulation in the no-tillage system.…”

“…The no-tillage system is considered a promising technique to reduce the effects of Indian summers when compared to the conventional tillage systems (FREITAS et al, 2014) by using crop residue for soil cover in order to keep in moisture (FREITAS et al, 2013). Mulch acts as an insulating agent, preventing sharp fluctuations in soil temperature and contributing to less evaporation of stored water and to better use of soil water by plants (MAROUELLI et al, 2006;BIZARI et al, 2009;OBALUM;OBI, 2010).…”