Soil Moisture And Temperature﹑Photosynthesis And Yield Of Rainfed Maize In The System Of Completely Mulched Alternating Narrow And Wide Ridges With Furrow Planting

This paper designed and implemented seven kinds of different planting treatment of corn in the filed of dry farming of loess plateau:Flat-planting without mulching (T1), Half-mulching and flat-planting (T2), Complete mulching and flat-planting (T3), Completely mulched alternating narrow and wide ridges with furrow planting (T4), Completely mulched alternating narrow and wide ridges with furrow planting+no-tillage during fallow (T5), Completely mulched alternating narrow and wide ridges with furrow planting+no-till with straw mulching during fallow (T6), Completely mulched alternating narrow and wide ridges with furrow planting+no-till with stubb le standing during fallow (T7) of the field comparison experiments. On determination of soil moisture during the maize growing dynamic, soil moisture between different locations of furrow, soil temperature, physiological state and photosynthetic and yield,researched on efficient mechanisms for water use and production mechanism of corn of completely mulched alternating narrow and wide ridges with furrow planting. The main conclusions are as follows:1. Since completely mulched alternating narrow and wide ridges with furrow planting (T4) can significantly improved soil moisture above 60cm layer of farmland, it is very beneficial for corn emergence and seedling growth. Land cover during fallow can increase the 0～60cm soil water content before sowing, and compared with flat planting, soil moisture content of furrow planting is high, the average moisture content of T4 is high than other treatments of 2.44%～14.19% of 0～60cm before planting; in planting to jointing stage of corn,0～60cm layer soil moisture storage of T4 is high than the flat-planting treatment and no-tillage during fallow treatment; the soil moisture content is significantly different in 0～60cm at different growth stages of completely mulched alternating narrow and wide ridges with furrow planting between large ridge, furrow and small ridge, and soil moisture content showed the furrow> Big Ridge> small ridge;but it changed unregularly below 60cm.2.The completely mulched alternating narrow and wide ridges with furrow planting (T4) treatment can promote premature and breakthrough temperature restriction of corn. The shortest growth season of corn is 157d, it is ahead of 2～8 d than flat-planting treatment(T2, T3), it is advanced 10～15d than no-tillage during fallow treatment (T5, T6, T7); The completely mulched alternating narrow and wide ridges with furrow planting (T4) reduced the variation of soil temperature, increased soil temperature at 15cm～25cm.3. The average photosynthetic rate is the highest of the whole growth period of the completely mulched alternating narrow and wide ridges with furrow planting (T4), it has photosynthetic capability than flat-planting treatment and no-tillage during fallow treatment, it is conducive to the formation of photosynthetic material. The explaination is that T4 of corn can effectively solve the problem of photosynthetic water in arid and semi-arid areas.The midday depression of completely mulched alternating narrow and wide ridges with furrow planting (T4), complete mulching and flat-planting (T3), complete mulching and flat-planting (T6) is weak than other treatments (T1, T2, T5, T7); The SPAD value before corn heading period of T4 is high than flat-planting treatment and no-tillage during fallow treatment, can increase the chlorophyll content of maize varieties, it laid the foundation for corn early growth and later high yield.4. In all stages of maize growth, morphological index and dry mass determination of completely mulched alternating narrow and wide ridges with furrow planting (T4) showed the highest, and the more arid in the reproductive stage, the completely mulched alternating narrow and wide ridges with furrow planting (T4) increased more obviously compared with flat-planting treatment and no-tillage during fallow treatment, indicating that completely mulched alternating narrow and wide ridges with furrow planting can reduce or lift the drought on growth of maize in arid and semi-arid areas. All of Maize Leaves of milky season of T4 is over a leaf than flat-planting treatment (T1, T2), over 1.4～2.2 leaves than wide ridges with furrow planting+no-tillage during fallow treatment (T5, T6, T7), the amount of dry matter of T4 is respectively high than the other treatments(T1 to T7) as 49.26%,11.51%,6.52%,23.97%,11.35%,15.90%.5. The completely mulched alternating narrow and wide ridges with furrow planting (T4) of corn planting can greatly increase corn yield and water use efficiency (WUE). Grain yield was T4> T3> T2> T6> T7> T5> T1 (immature), the production of T4 was 10341.7 kg/hm2, it is respectively high than the other treatments as 9.86%,26.76%,31.59%,45.77% and 57.59%; WUE showed T4> T3> T6> T2> T7> T5, the WUE of the completely mulched alternating narrow and wide ridges with furrow planting (T4) was 34.33 kg/(mm·hm2), it increased respectively by 9.19%,13.90%,17.41%,32.39%,39.38% than the other. It indicated that the implementation of completely mulched alternating narrow and wide ridges with furrow planting can significantly increase production in the loess plateau in arid and semi-arid areas, it showed more significant role in increasing production especially in drought years.