乾溼交替灌溉模式對水稻產量及品質之影響

Effects of Alternate Wetting and Drying Irrigation on the Grain Yield and Quality of Rice

丁文彥(Wen-Yen Ting)

乾溼交替灌溉 ； 水稻 ； 稻米品質 ； 產量 ； Alternate wetting and drying irrigation ； Japonica rice ； Grain quality ； Grain yield

臺東區農業改良場研究彙報

34輯（2024 / 06 / 01）

47 - 58

繁體中文;英文

為因應水資源日漸缺乏及提高農業灌溉用水效益，本試驗以水稻高雄139號、臺梗2號、臺東30號及臺東35號為材料，利用乾溼交替灌溉探討適合東部地區的節水栽培模式。2021年及2022年調查水稻全生育期用水量顯示，1期作每公頃用水量約8,789 m^3～14,346 m^3，2期作每公頃約10,270 m^3～11,910 m^3，其中以曬田後至抽穗期間的用水量最高。2021年以10 cmPVC豎管進行乾溼交替灌溉試驗，結果發現，兩期作各減少約1/2灌溉次數，節省用水量32.22%～29.03%；2022年改採15 cm PVC豎管進行試驗，兩期作各減少17次及12次灌溉次數，節省用水量達54.37%～43.38%，節水成效較10cm處理佳。AWD處理對於1、2期作水稻農藝性狀的影響，均以株高的減少最顯著；2期作的每叢穗數亦有顯著降低的情形。米質方面，AWD處理有蛋白質含量較低，食味值較高的現象。節水栽培對於2021年1期作水稻產量的影響以臺東35號減產22.6%較高；2022年1期作則影響高雄139號及臺東35號的產量表現，高雄139號減產21.3%，臺東35號減產比例達27.6%；然AWD處理對於2期作的水稻產量表現無顯著差異。綜合節水成效及缺水逆境對水稻產量及品質影響等因素，在東部地區推動乾溼交替灌溉模式，若先以10 cm處理進行低強度節水措施，再依水稻品種對逆境的適應性調整節水強度，應屬較為可行之方法。

This study aims to establish a cultivation model with alternate wetting and drying irrigation(AWD) base on stable production and grain quality of rice cultivars. We found the field irrigation requirements of the first season and second season were 8,789 m^3/ha ~ 14,346 m^3/ha and 10,270 m^3/ha ~ 11,910 m^3/ha, respectively in 2021 and 2022 with the conventional cultivation; the maximum irrigation requirement period founded during the field drying to heading stage. The results indicated that the yield of TT35 cultivar underground 10 cm AWD was 22.6 % lower than conventional cultivation of first season in 2021. We modified the AWD model by underground 15 cm in 2022, found that the yield of TT35 cultivar was 27.6% lower than conventional cultivation of first season, the main caused by less panicle numbers. Both yields of second season in 2021 and 2022 had no significant difference than conventional cultivation, due to the precipitation during the growth period. Howere, the brown rice rate, milled rice rate and volumetric weight had no significant difference under AWD, but the protein content of milled rice were decreased, the taste value were increased under AWD. Therefore, we can establishe a useful irrigation regime in addition to the AWD during the whole growth period of rice, corresponding at the different growth period, can be used as one of the effective strategies to maintain rice production and grain quality in Taitung area.