Low temperature from late winter to early spring is a main restraint to high yield in winter wheat production in the northern part of North China Plain. We attempted to artificially increase the temperature during this period through phased plastic film mulching. A field experiment was carried out in the 2012–2013 and 2013–2014 growing seasons with several treatments differing from artificial warming period. Compared with the normal condition (control), mulching since January 25 or February 1 resulted in 167.7–176.8°C increment of accumulated temperature from late January to early March, and mulching one week ear-lier contributed to higher accumulated temperature by 23.0–49.7°C. Wheat seedlings under artificial warming showed earlier re-vival and growth than the control. And the subsequent growth stages were prolonged for 4–10 days because of the relative lower temperature after the plastic film was removed. The earliest warming treatment was most favorable to dry matter accumulation, translocation, and yield enhancement among all treatments. Compared with the control, the earliest warming treatment with mulching increased the dry matter weight and leaf area index at anthesis stage by 18.8% and 14.7%, respectively; as well as pro-longed active photosynthetic duration by more than 10 days, and increased leaf area duration by 43.6%, spike number per hectare by 0.48–0.98 million, kernel number per spike by 3.9–4.5 kernels, and thousand-kernel weight by 2.5–5.6 g. The final yields of the earliest warming treatment were 37.5% and 18.9% higher than those of the control in the cool 2012–2013 and the warm 2013–2014 growing season, respectively, and the maturity date was five days earlier than that of control in the 2013–2014 grow- ing season. Our results indicate that artificial warming by phased mulching with plastic film is an applicable technique in wheat production in North China Plain.%针对华北平原北部冬春温度变化与冬小麦生长发育所需适宜温度间的矛盾,以及由此造成的冬小麦相对低产问题,于2012—2013和2013—2014连续2个生长季,通过大田试验研究了晚冬早春搭建棚室阶段性升高田间温度对小麦产量的影响。结果表明,2月20日前后麦田塑膜覆盖每提前1周积温提高23.0~49.7℃,1月下旬至3月上旬的整个升温阶段内可增加积温167.7~176.8℃,从而小麦生长发育提前。塑膜揭除后形成的相对低温环境使后续各生育阶段持续时间延长4~10 d。与常规种植(对照)相比,最早增温处理的开花期干物质产量提高18.8%,叶面积指数提高14.7%,花后光合势增加43.6%,花后净光合速率高值持续期延长10 d以上；返青后各生育阶段的延长促进了干物质积累和向籽粒转移,有效穗数增加48~98万hm-2、单穗粒数增加3.9~4.5粒、千粒重增加2.5~5.6 g。在全生长季积温较少的2012—2013年度,最早增温处理的籽粒产量提高37.5%,在积温较多的2013—2014年度增产18.2%,并提前5 d成熟。晚冬早春农田阶段性覆膜增温是有效提高小麦籽粒产量的新型方法,提前并延长了生长发育和干物质累积的时间是改善小麦产量构成因素和获得高产的原因。
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