干旱区控制灌溉下水稻光合特性与蒸腾效率研究

Photosynthesis Characteristics and Transpiration Efficiency of Rice Plants under Controlled Irrigation Technology in Arid Region

于2011-2012年在干旱区（新疆石河子市）开展田间小区试验，研究淹灌（W1）、控制灌溉（W2）和旱作（W3）等栽培模式下的产量构成、光合特性及蒸腾效率，以期为干旱区水稻高产高效栽培提供理论依据。研究结果表明：开花前，净光合速率（Pn）在W1和W2处理间差异不显著（P〉0．05），但花后，W1处理Pn分别高出W2、W3处理11．29％～20．91％和38．65％～52．03％；在饱和土壤含水量条件下，W2处理净光合速率较W1处理轻微降低，羧化效率、光饱和点和光补偿点均可与W1持平，并显著高于W3处理（p〈0．05），W2处理花后光合生产能力受限主要因其在非饱和土壤含水量条件下大幅降低所致；W1处理全天各时间段Pn高于W2和W3处理，午后时段处理间差异较上午更大；最终，W2处理产量仅降低4．43％～18．72％，而W3处理降低31．23％～39．45％；在整个生育期，W2处理蒸腾效率最大，显著高于W1、W3处理（P〈0．05）。综上所述，W2处理在干旱区表现出高产高效生产潜力，提升灌浆期午后光合生产能力可能对于进一步提高旱区水稻产量具有重要作用。

To investigate the effects of water regimes on yield formation, photosynthetic characteristics and transpiration efficiency of rice plants in arid region, plot experiments were conducted in 2011 and 2012 in Shihezi City with three water treatments, including flooding irrigation （W1） , controlled irrigation technology （W2） and aerobic rice （W3）. The results showed that there was no significant difference for net photosynthetic rate （Pn） in W1 and W2 treatments before anthesis, but W1 treatment was 11.29% - 20. 91% higher than W2 treatment, and 38.65% - 52. 03% higher than W3 treatment after anthesis across both years. Further analysis indicated that little difference of the parameters of P, carboxylation efficiency, saturation light intensity, and compensation light intensity were existed in WI and W2 treatments in saturated soil moisture, the lower P in W2 and W3 treatments than that in W1 treatment was mainly due to significantly decreased P in W2 and W3 treatments when soil water content was unsaturated in 2011 and 2012 （p 〈 0.05）. Moreover, the diurnal changes of Pn was higher in W1 treatment than that in W2 and W3 treatments during whole observed times, and the difference was greater on forenoon （before 12：00） than on afternoon （after 14：00） among treatments. Finally, the grain yield in W2 and W3 treatments only decreased by 4.43% -18.72% and 31.23% -39.45% when compared with W1 treatment considering both years. The transpiration efficiency in W2 treatment was always significantly greater than that in W1 and W3 treatments during whole growth stages in both years （p 〈 0.05）. Generally speaking, the W2 treatment performs high grain yield and high water use efficiency in arid region, meanwhile, the grain yield in W2 treatment could be increased when improving photosynthetic produce ability in the afternoon at grain-filling stage.