| 摘要: |
| 【目的】充分利用土壤贮水和自然降水，减少灌溉水投入，研究依据自然供水状况确定最佳畦灌时期和次数的畦田节灌技术。【方法】试验在播种期水分管理一致的基础上，设置4个水分处理，W0为不灌水处理，W1为灌3水处理（越冬水+拔节水+开花水），W2为灌2水处理（拔节水+开花水），W3为灌1水处理（开花水），研究了畦田节灌对冬小麦开花后旗叶SPAD值、光合特性、产量及水分利用效率的影响。【结果】与W2处理相比，W3处理开花后旗叶SPAD值、净光合速率、干物质同化量及其对籽粒的贡献率均降低，穗数、穗粒数和籽粒产量减少，但水分利用效率较高；W1处理籽粒产量及其构成因素没有明显变化，但水分利用效率显著降低。与W0处理相比，W3处理的籽粒产量增幅达16.2%~20.7%。结合关键生育时期土壤相对含水率分析，冬小麦越冬期0~20 cm和0~40 cm土层土壤相对含水率分别不低于65%θf（θf为田间持水率）和66.8%θf时，灌溉越冬水对籽粒产量无明显增益作用。拔节期0~20 cm土层土壤相对含水率降至50.6%θf及以下，即使0~200 cm土层土壤含水率接近80%θf，仍不能满足拔节后冬小麦对水分的需求，应及时灌溉拔节水。开花期0~20 cm和0~200 cm土层土壤相对含水率分别为24.8%θf~35.6%θf和57.9%θf~58.8%θf，及时灌水增产幅度较大。【结论】在冬小麦播种期供水适宜的条件下，于拔节期和开花期实施畦灌，生长季内灌2水，能获得较高的籽粒产量和水分利用效率，避免过量灌溉。 |
| 关键词: 冬小麦； 畦灌； 灌水时期； 光合特性； 产量； 水分利用效率 |
| DOI：10.13522/j.cnki.ggps.2017.0724 |
| 分类号: |
| 基金项目: |
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| Response of Photosynthesis, Yield and Water Use Efficiency of Winter Wheat to Schedule of Border Irrigation |
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WU Baojian, WANG Dong
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College of Agronomy, Shandong Agricultural University/State Key Laboratory of Crop Biology/Key Laboratory of Crop Ecophysiology and Farming System, Ministry of Agriculture, Taian 271018, China
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| Abstract: |
| 【Objective】 This paper investigates the consequent impact of frequency and timing of border irrigation on SPAD value, photosynthetic rate of flag leaf after anthesis, yield and water use efficiency of winter wheat under different border irrigation schedules, aiming to improve use efficiency of both soil water and precipitation by the plant. 【Method】 We compared four treatments after the seedling emerged: rainfed (W0), irrigating at wintering, jointing and anthesis stage respectively (W1), irrigating at jointing and anthesis stage respectively (W2), irrigating at anthesis only (W3). 【Result】 Compared with W2, W3 reduced the SPAD, net photosynthetic rate of flag leaf after anthesis, the assimilation of dry matter and its contribution to grain, the number of spikes, grains per spike and grain yield, despite its increases in water use efficiency. In contrast, the yield and yield components in W1 were approximately the same as that in W2 in spite of its significant decrease in water use efficiency. Compared with W0, W1 increased grain yield by 16.2%~20.7%. In all treatments, the soil moisture in 0~20 cm and 0~40 cm soil was more than 65% and 66.8% of the field capacity respectively at wintering stage, and thus irrigation at this stage had no significant effect on wheat grain yield. Root uptake and evaporation reduced the moisture in 0~20 cm soil quickly to 50.6% of the field capacity event though the soil moisture in 0~200 cm was close to 80% of the field capacity. Therefore, irrigation was required to replenish the water lost via evapotranspiration. When soil water content in 0~20 cm and 0~200 cm soil at the anthesis stage was 24.8%~35.6% and 57.9%~58.8% of the field capacity respectively, timely irrigation could greatly increase the yield. 【Conclusion】 Irrigation at jointing and anthesis stage can improve both grain yield and water use efficiency. |
| Key words: winter wheat; border irrigation; irrigation stage; photosynthetic characteristics; yield; water use efficiency |
