Abstract Efficient water use in agriculture is a global demand, and in this context, the implementation of a sprinkler irrigated rice system has become a reality. Besides saving water, proper management of a sprinkler irrigated system can maintain high levels of productivity. This study aimed to determine the effect of soil water tension on rice crop production, in both vegetative and reproductive stages, as well as to evaluate the effect of soil water availability and physicochemical attributes on biometric and reproductive characteristics associated to rice grain yield under sprinkler irrigation. The experiment was carried out at the Lowland Experimental Station, Embrapa Clima Temperado, Capao do Leao – Rio Grande do Sul, Brazil, during two growing seasons, in an area irrigated by a lateral-move sprinkler irrigation system. The following irrigation managements were evaluated: irrigation, when the mean soil water tension was i) 10 kPa; ii) 20 kPa; iii) 40 kPa; iv) 40 kPa on vegetative and 20 kPa on reproductive stages and v) 40 kPa on vegetative and 10 kPa on reproductive stages. Under sprinkler irrigation, rice plant development was impaired as soil water tension increased, evidenced by a reduction in plant heights. Soil water tension of 10 kPa was adequate to manage the sprinkler irrigation in rice, especially in the reproductive stage and when using cultivars developed for flooded environments. Rice development and yield were affected by increasing soil bulk density and acidity. Rainwater represented approximately 40 % of the water used by sprinkler irrigated rice during the crop cycle, contributing with the reduction of irrigation water use.

中文翻译：

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低地水稻喷灌：作物产量及其组成部分作为不同物候期可用水量的函数

摘要 农业高效用水是全球需求，在此背景下，实施喷灌水稻系统已成为现实。除了节水外，正确管理喷水灌溉系统可以保持高水平的生产力。本研究旨在确定土壤水分张力对水稻在营养和繁殖阶段的影响，并评估土壤水分可用性和物理化学属性对喷灌下水稻产量相关的生物特征和繁殖特征的影响。 . 该试验在巴西南里奥格兰德州南里奥格兰德州 Embrapa Clima Temperado 的低地试验站进行，在一个由横向移动喷灌系统灌溉的地区进行。评估了以下灌溉管理：灌溉，当平均土壤水分张力为 i) 10 kPa 时；ii) 20 kPa；iii) 40 kPa；iv) 营养阶段为 40 kPa，生殖阶段为 20 kPa，以及 v) 营养阶段为 40 kPa，生殖阶段为 10 kPa。在喷灌下，随着土壤水分张力的增加，水稻植株的发育受到损害，这可以通过植物高度的降低来证明。10 kPa 的土壤水分张力足以管理水稻的喷灌，特别是在生殖阶段和使用为洪水环境开发的栽培品种时。水稻的发育和产量受到土壤容重和酸度增加的影响。雨水约占作物周期中喷灌水稻用水量的 40%，有助于减少灌溉用水。