运城盆地不同播期小麦春季冻害风险评价

为评价山西南部地区不同小麦品种在不同冬前积温下的春季冻害风险,明确适应当前气候变化的适宜播期和品种,分别于2017-2018霜冻发生和2018-2019霜冻不发生的两个不同气候年型,在山西运城盐湖区采用播期、品种二因子裂区试验设计,对3个不同生态类型小麦品种(济麦22、周麦18和西农529)在不同冬前积温下的春季冻害风...

Risk Assessment of Spring Freezing Injury of Wheat at Different Sowing Dates in Yuncheng Basin

In order to evaluate the risk of the spring frost damage to different wheat varieties in southern region of Shanxi under different accumulated temperature before winter and define the suitable sowing date and variety of adapting the change of current climate， two-factor splitting zone test including sowing date and variety was used to analyze the risk of wheat spring freezing injury. The test were arranged in two different climatic years from 2017 to 2018 （frost occurrence） and 2018 to 2019 （no frost）， and 3 different ecological types of wheat varieties（Jimai 22， Zhoumai 18 and Xinong 529） were sowed at different date in Yanhu district of Yuncheng. The results showed that the accumulated temperature before winter （sowing date） had significant effect on wheat jointing and the risk of wheat spring freezing injury， the higher accumulated temperature before winter （the earlier sowing date） advanced the wheat jointing stage and increased the risk of freezing damage in spring. And variety with strong spring quality had higher risk to freeze damage. The average risk of frost damage in late March and early April were the highest when the accumulated temperature （≥0 ℃） before winter was 616.3 ℃， and were lowest when the accumulated temperature before winter was 390.1 ℃. In the year of frost occurrence， with the decrease of accumulated temperature before winter， the degree of freezing of wheat ear was reduced， the process of ear development was delayed， the relative membrane permeability was decreased， the content of MDA was decreased， and the activity of antioxidant enzymes were enhanced. The yield was consistent with the degree of freezing damage and the trend of evaluation of freezing damage. In no frost year， the yield showed a decreasing trend with the decrease of accumulated temperature before winter. However， the accumulated temperature before winter was moderately reduced， which had a little effect on the yield. Under the climate warming situation， the wheat yield could be more stable when the accumulated temperature （≥0 ℃） before winter was about 250～390 ℃， and the risk of freezing injury should be lower. Reducing the accumulated temperature before winter should be an effective way for wheat in environment of climate change.