| Rainfall is unevenly distributed among years and seasons in Northeast China.Annual and seasonal drought and waterlogging disasters are key factors restricting maize yield.Years of continuous stubble rotation tillage and neglect of the input of organic materials make the soil plough moved up and the soil water storage preservation ability decreases,which cause progeria and seriously limits the yield of maize.In order to solve above problems,a root box straw return test was set up in a large shelter of Shenyang Agricultural University from 2017 to 2018.Straw burying(T1)and straw incorporation(T2)as two approaches of straw amendments were conducted combining with three depths of 15cm(D1),30cm(D2),and 45cm(D3)for straw incorporation,digging over soil at above 3 depths without straw presence as control treatments in this study.During seedling and silking stages of maize,drought and water logging stresses were introduced respectively,in order to analysis the effect of straw incorporation modes on soil physical and chemical properties,with the artificial installation of rain shelter and drip irrigation facilities,spatial distribution characteristics of root system,growth and development of spring maize and its yield.The results show that:Compared with the CK2 treatment,the soil compaction on 10~45 cm on-row and 0~30 cm inter-row were significantly reduced by S1T1D2,and compared with the S1T2D2,the soil compaction on 10.0~27.5 cm on-row and 15.0~22.5 cm inter-row soil was significantly reduced by S1T1D2.Under drought stress condition,except 0~10 cm soil layer,the volumetric water content of S1T1 were higher than or equal to S1T2 and CK,and under waterlogging stress condition,the soil water content distribution of S1T1D2 was uniform and the average value was the lowest.Under the condition of water stress,the root length spatial distribution of S1T1 and S1T2 were significantly higher than that of CK.S1T1D2 could not only increase the water distribution range of roots,but also improve the dry quality of deep roots and enlarge the vertical distribution range of roots.There was no significant difference in plant height and stem diameter and leaf SPAD,among different incorporation methods and the same incorporation depth.There was no significant difference among other treatments at 30 cm incorporation depth,but at grain filling stage was significantly lower than other treatments.Under D1 and D3 conditions,the leaf area of the straw incorporation treatments were significantly higher than that of CK.In 2017 and 2018,under drought stress the leaves MDA content of S1T1D2 was significantly lower than that of the other two treatments at D2.The dynamic analysis of MDA content under waterlogging stress in 2018 showed that the leaves MDA content of S1T1D2 was significantly lower than S1T2D2 and CK2.Under the D2 and D3 condition,the stem bleeding intensity of S1T1 and S1T2 were significantly higher than that of CK.There were no significant difference in yield characters and grain yield in 2017 and 2018.To sum up,S1T1 and S1T2 could reduce soil compaction,increase soil buffering capacity,optimize root distribution,promote lateral root growth and root pruning,and obtain larger leaf area and dry matter accumulation.S1T1D2 not only had the strongest soil buffering ability and the broadest distribution of root system,but also the lowest malondialdehyde content in leaves and the largest stem injury flow in the field.So it is the suitable straw incorporation mode in the similar climate area of Northeast China. |
PDF Full Text Request