隔年秸秆还田对连作玉米养分积累及叶片生理特性的影响

Effects of Straw Returning to Field in the Alternate Years on Nutrient Accumulation and Leaf Physiological Characteristics of Continuous Cropping Maize

以秸秆不还田为对照,设置秸秆深翻还田和旋耕还田配施秸秆腐熟剂、深翻和旋耕还田不施秸秆腐熟剂5个处理,测定玉米茎秆、叶片、穗部和子粒氮磷钾养分积累量及叶片生理活性,研究秸秆还田配施秸秆腐熟剂对玉米生长及产量的影响。结果表明,不同秸秆还田方式显著提高玉米穗位叶以上第3叶(上位叶)及穗位叶以下第3叶(下位叶)叶绿素含量、叶片超氧化物歧化酶(SOD)活性、茎鞘氮和钾积累量,并提高玉米产量,增产率为7.56%~28.00%。旋耕和深翻秸秆还田配施腐熟剂处理显著提高穗位叶叶绿素含量,显著降低叶片丙二醛(MDA)活性,显著提高叶片磷积累量;深翻还田配施腐熟剂极显著提高叶片、穗部、子粒氮积累量。冷凉地区玉米秸秆还田提高玉米叶片生理活性,旋耕还田配施秸秆腐熟剂增产率高,干物质积累量较多;深翻还田配施腐熟剂显著提高玉米叶片、穗部和子粒氮积累量。

In order to improve the efficiency of maize straw returning to field in cold area,we set five treatments,rotary tillage without straw returning(CK),straw returning with deep plowing(DR),straw returning with rotary tillage(RR),straw returning with deep plowing tillage+straw decomposition agent(DR+D),straw returning with rotary tillage+straw decomposition agent(RR+D).Then we measured the accumulation amount of nitrogen,phosphorus and potassium in maize stem,leaf,ear and grain,and evaluated the physiological activity of leaf,aiming to study the effects of straw returning together with straw decomposition agent on the growth and grain yield of maize.The results showed that all the straw returning method significantly increased the chlorophyll contents of both upper and lower leaves,significantly increased SOD activity,and increased the nitrogen and potassium accumulation in stem and sheath and grain yield.The yield was increased from 7.56%to 28%.Treatments DR+D and RR+D could increase the chlorophyll contents in leaf significantly,reduce the MDA activity of leaves,and increase phosphorus accumulation in leaf and potassium accumulation in stem and sheath.Moreover,DR+D extremely significantly increased the nitrogen accumulation in leaf,panicle and grain.In conclusion,straw returning could improve the physiological activity of corn leaf.Especially,RR+D gained the most yield and dry matter accumulation amount,and DR+D improved nitrogen accumulation in leaf,panicle and grain most.