Previous reports from laboratory‐controlled experiments and models considered that a shorter reproductive period could be the main reason for wheat yield reduction in the warmer world. However, this conclusion needs to be proved carefully by field‐scale experiments. In this study, a field‐scale continuous open‐warming experiment was conducted to quantify the adjustment of winter wheat growth and yield under conventional tillage (CT) and no‐till (NT) systems in the North China Plain (NCP). Canopy temperatures were warmed using infrared heaters between 1.0 and 1.6°C (daytime and nighttime, respectively) above the control. Wheat yields under CT were not significantly reduced over the two seasons (2010 and 2011), but yields under NT were 3.3% and 6.1% lower, respectively. The growing seasons for both CT and NT were shortened 6 days in 2010 and 11 days in 2011; however, the reproductive periods were maintained. The shortened days were due to a significantly shorter springtime re‐greening stage followed by minimal changes in other phenological stages (jointing, flag completed, heading, anthesis, and grain‐filling). The temporal advance by warming resulted in lower growing‐season mean air temperatures (MAT) for warmed plots than the control from 0.23 to 4.22°C for the same subsequent phenological stages. Warming increased the number of tillers m−2 and kernel weight, but tended to decrease the number of spikes m−2 in the two tillage systems. The heavier kernels offset the yield reduction from smaller number of spikes. Warming increased the wheat aboveground biomass from 10% to 20% suggesting the potential to sequester more CO2. This study suggests that winter wheat might adjust its growth (shortened vegetative period to maintain reproductive period) to partly compensate for the negative effects from global warming in this temperate irrigated cropland.
The application of bioorganic fertilizer affects rhizosphere microbes and further improves soil fertility in farmlands. However, the effects of different fertilizers on rhizosphere bacterial community diversity and structure of winter wheat remains unclear. In this study, we explored the effects of different fertilization treatments (no fertilizer added, CK; nitrogen fertilizer, NF; bioorganic fertilizer, BOF) on the rhizosphere bacterial community of winter wheat in the North China Plain. Rhizosphere soil treated with BOF had a higher Shannon index than that of CK and NF. The relative abundance of the Proteobacteria treated with BOF was significantly higher than that of NF, while the Acidobacteria and Planctomycetes were significantly lower. The redundancy analysis (RDA) and Mantel test showed that soil bacterial communities were significantly correlated with pH, nitrate, available phosphorus (AP), and available potassium (AK). Our findings indicated that BOF increased bacterial diversity and the relative abundance of copiotrophic bacteria in rhizosphere soil, while NF reduced bacterial diversity and increased the relative abundance of oligotrophic bacteria. The increase in copiotrophic bacteria in the rhizosphere of winter wheat could indicate an increase in soil nutrient availability, which might have positive implications for soil fertility and crop production.