旱地秸秆还田对小麦花后光合特性及产量的影响

摘要

在旱地设置旋耕（ CK）、旋耕还田（ RS）、免耕还田（ NS）、深松还田（ SS）和深耕还田（ DS）5个处理，研究了不同处理对小麦花后旗叶光合速率、气孔导度、胞间CO2浓度等光合特性及产量的影响。结果表明，由于秸秆还田对土壤及水分环境的改变，小麦旗叶光合特性总效应为秸秆还田大于不还田。不同的秸秆还田模式光合特性表现为SS＞NS＞DS＞RS，秸秆还田尤其减缓了灌浆中后期叶绿素的降解。秸秆还田在不同程度上降低了小麦出苗率，SS处理和NS处理出苗率最低，分别比CK低21．25％和16．5％，穗数较低，但由于光合能力较强，千粒质量最高，穗粒数也高于其他处理，SS处理产量显著高于其他还田处理，综合本试验结果，在旱地推荐深松还田的耕作模式。%The photosynthetic rate , stomata conductance , intercellular CO 2 concentration , yield and some other photosynthetic characteristics were studied under five treatments of winter wheat in dryland .The five treatments are rotary tillage without straw return(CK),rotary tillage with straw(RS),no-tillage with straw(NS),subsoil tillage with straw(SS),deep plowing tillage with straw(DS).The result showed that all the photosynthetic characteristics in flag leaf of tillage with straw return was greater than the tillage without straw return ,this is due to the different soil moisture condition under tillage with straw return .The photosynthetic characteristics of tillage with straw return showed as SS>NS>DS>RS,tillage with straw return in particularly slowing down the degradation of chlorophyll at later grain filling stage .Tillage with straw return reduced the emergence rate and spike number ,emergence rate of SS and NS reduced 21.25%and 16.5%compared with CK treatment .The yield,1000-grain weight and Grains per spike of SS were much higher than the other treatments because of the higher photosynthetic rate .Integrated results of this trial ,the SS treatment was recommended in dryland .