| For plain irrigation area of Inner Mongolia have the characteristic of existing hard farmland plough bottom, shallow top layer, poor soil structure and reproducibility of realizing large mechanized and high yield of spring core is poor. This study set three treatment of35cm of deep loosening (S35),25cm of deep loosening (S25) and15cm of shallow rotary (CK) in2011and2012. After breaking the plough through the deep loosening measures, study the effect of changes in soil structure and tight environment on root conformation after breaking the plough deep loosening measures, the rules of aboveground carbon and nitrogen accumulation and transportation and the characteristics of Leaf photosynthesis aging in grouting period, then discussing the mechanism of increasing production by mechanized deep loosening. The results are as follows:(1) Deep loosening measures can significantly reduce tight environment of soil layer from0-40cm and with the increase of the depth of the deep loosening, the lower firm effects more than permanent, especially reduce the inter-row tight environment more than obvious.(2) Deep loosening measures can enhance water storage efficiency of the soil deep (40-60cm) and enlarge soil water stable aggregate particle size effect of the soil deep (20-40cm) in late growth period. Effect in silking stage is most obvious, and increasig the efficacy by depth of the deep loosening is more obvious.(3) Compared with CK treatment, after the S35and S25treatment, root dry weight per plant do not increase in filling stage, instead of having a tendency to lower than CK treatment. S35can increase inter-row20-60cm soil layer distribution of root weight proportion, and along with the deepening of soil increase gradually, S25treatmen can increase root weight ratio of0-20cm line position.0-60cm soil layer of root length of S35and S25treatment is46.24%and33.53%higher than that of CK treatment, respectively, root surface area are all19.59%higher than that of CK treatment, the root length and root surface area all show down trend, and with the increase of the depth of the deep loosening is more significant. Compared with CK treatment, it is most significant of the S35treatment to increase its leading position in deep soil layer distribution of root length, root surface area ratio. Along with the deepening of the soil gradually decreased, root length and root surface area distribution proportion of S25treatmen gradually reduce compared with CK treatment, S25treatment reduces the0-20cm line distribution ratio; increases the20-60cm distribution ratio; increases the0-40cm and reduced the40-60cm distribution proportion.Deep loosening measures can promote the growth of root on diameter class of0-0.2mm, and increase the distribution proportion of fine root in deep especially. Meanwhile, deep loosening measures can increase the specific root length and improve the root characteristics in30-40cm soil layer. S25can increase the distribution proportion of diameter class of0-0.2mm in20-40cm soil layer and increase the specific root length in30-50cm soil layer significantly. S35can increase the distribution proportion of diameter class of0-0.2mm in40-60cm soil layer and increase the specific root length in30-60cm soil layer significantly.(4) With the depth of the deep loosening, delay the rod3leaf SAPD reduces, nitrogen output of Vegetative organs and the lower blade is obvious. That the smaller population leaf area index decreased, maintaining high photosynthetic capacity more than obvious, aboveground dry matter and n accumulation is more significant, especially in spinning18to36days.Above all, S35treatment is better to break the plough, and reduces soil tight environment, increas the late deep soil water storage and the water stability aggregate particle size is most obvious, Improves root growth and architecture more than significant, delaies leaf senescence more than obvious, Ensures that the late high aboveground dry matter accumulation and nitrogen accumulation, and thus within36days after silking lay a solid foundation for production. |
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