Rice Adaptation to Aerobic Soils: Physiological Considerations and Implications for Agronomy

Abstract

Aerobic culture is a water-saving technique for direct-seeded rice cultivation. Growing rice under continuously unsaturated soil conditions can maximize water-use efficiency and minimize both labor requirements and greenhouse-gas emissions. Under a temperate climate, aerobic culture can produce a rice yield greater than 9 t ha-1 especially in central Japan (11.4 t ha-1). Aerobic culture using large-scale center-pivot sprinklers is being established in the central United States, where yields can surpass 10 t ha-1. However, yields remain at less than 8 t ha-1 in the tropics. The high yield of Japanese aerobic culture is mainly attributed to vigorous nitrogen uptake during the reproductive stage, which allows rice plants to produce more spikelets and biomass. Fertilizer management for aerobic culture must satisfy both the nitrogen demand and control spikelet density to achieve an appropriate sink-source balance. Unfortunately, the poor development of the root system in rice limits its water uptake from unsaturated soil. Adaptive responses such as adventitious root emergence, lateral root branching, and deep root penetration would protect the plants against dehydration stress in aerobic culture. Intermediate plant height with a few large tillers rather than semi-dwarf stature with profuse tillering should be a suitable plant type for aerobic culture, and plants should show leaf expansion despite fluctuations of soil moisture. The development and identification of suitable genotypes and crop management options are underway worldwide for more resource-use efficient and productive aerobic rice culture.

Tecnologías para ahorrar agua en el cultivo de arroz

“…2) para el arroz cultivado con tecnologías alternativas (T.A) y el sistema convencional de arroz inundado (SC). En ellas, se resaltó la zona tropical (T) y subtropical (ST) donde se realizó el estudio, ya que el arroz cultivado en el trópico tiene características diferentes a las del subtrópico (1 Como aspectos importantes a tener en cuenta, el pivote central se adapta a topografías onduladas en cualquier edad del cultivo, reduce los costos operativos del riego tradicional por inundación, permite la aplicación eficiente de fertilizantes y químicos con uniformidad, y se estima que tiene una vida útil promedio de 20 años.…”

“…El arroz (Oryza sativa L) es básico en la canasta familiar para cerca de la mitad de la población mundial (1), el segundo cereal con mayor área cosechada (2) y un cultivo que ejerce una gran presión sobre el recurso hídrico (PSRH; (3)). El sector agrícola en Colombia demanda anualmente 54% del agua consumida (19386 millones (M) de m 3 ), de los cuales 4185 Mm 3 son implementados para el cultivo de arroz y de estos, se estima que solo 962 Mm 3 son consumidos de forma efectiva (4).…”

Zinc Availability and Dynamics in the Transition from Flooded to Aerobic Rice Cultivation

“…Currently, aerobic cultivation occupies approximately 20% of the total rice grown in China, Philippines and India [22]. In China, new lines of aerobic rice have recently been developed with estimated yield potential of 6-7 t ha -1 [21].…”

Produtividade de arroz irrigado por aspersão em terras baixas em função da disponibilidade de água e de atributos do solo

“…Estudos têm sido realizados em diversas partes do mundo para avaliar a adaptação e a viabilidade do cultivo de arroz irrigado em sistemas que proporcionam economia de água em comparação ao sistema inundado, até mesmo com o uso da irrigação por aspersão (Kahlown et al, 2007;Vories et al, 2013;Kato & Katsura, 2014). Esses autores chegaram a observar economia aproximada de 50% no uso da água pelo arroz irrigado por aspersão, quando comparado com o irrigado por inundação.…”