灌浆期涝渍对小麦旗叶抗氧化酶活性的影响

目的:研究灌浆期涝渍对小麦旗叶抗氧化酶活性的影响。方法:以烟农19为试验材料,在大田条件下进行冬小麦灌浆期的渍害和涝害处理,分析了小麦旗叶抗氧化酶活性的变化及MDA含量的变化。结果:与对照组处理相比,渍涝害处理后的小麦旗叶SOD活性在灌浆前期高于对照组,在灌浆中后期低于对照组。渍涝害处理后的小麦旗叶POD活性在灌浆前期高于对照组,在灌浆中后期低于对照组。渍害处理后和涝害处理后的小麦旗叶CAT活性在整个灌浆期都高于对照组,且随着处理天数的增加小麦旗叶CAT活性降低。渍涝害处理后的MDA含量在整个灌浆期都高于对照组,且旗叶MDA含量随着处理天数的增加而增高。结论:通过抗氧化酶活性的变化与MDA含量的变化可见,在小麦浆期涝渍胁迫中,CAT在旗叶抗氧化酶系统中起到主要作用,POD和SOD起到次要作用。

玉米涝灾后管理技术

2021年7月11~12日天津市宁河区普降大雨到特大暴雨,使部分农田出现不同程度的积水和淹泡,对玉米生长极为不利。目前,宁河区麦茬夏玉米大多处于苗期,此期若土壤水分过多或积水,容易形成苗期渍涝害,使玉米根部受害甚至死亡。为防止渍涝害和各种病虫害的发生,应加强田间管理,具体管理措施如下。

Efficient Management of Nitrogen Fertilizers for Flooded Rice in Relation to Nitrogen Transformations in Flooded Soils

Recent progresses in efficient management of nitrogen fertilizers for flooded rice in relation to nitrogen transformations in flooded soil were reviewed.Considerable progress has been achieved in the investigation on the mechanism of ammonia loss and the factors affecting it .However,little progress has been obtained in the investigations on nitrification-denitrification loss owing to the lack of method for estimating the fluxes of gaseous N products.Thus,so far the management practices developed or under investigation primarily for reducing ammonia loss are feasible or promising,while those for reducing nitrification-denitrification loss seem obscure,except the point deep placement. In addition,it was emphasized that the prediction of soil N supply and the recommendation of the optimal rate of N application based on it are only semi-quantitative.The priorities in research for improving the prediction are indicated.