Effects Of Deep Loosening And Soil Compacting On Water Consumption Characteristics And Grain Yield Of Winter Wheat

This experiment was conducted with wheat cultivar Jimai22. Water consumptioncharacteristics and grain yield formation were analyzed by the tillage patterns in the mainplots and the soil layer depths of supplemental irrigation in sub-plots and the relative soilmoisture in the sub-sub-plots. The tillage patterns were rotary tillage (G1), rotary tillage afterdeep loosening (G2), harrow pressing after deep loosening and rotary tillage (G3), oncerolling after deep loosening and rotary tillage (G4), twice rolling after deep loosening androtary tillage(G5). The irrigation treatments were conducted at jointing and anthesis. The soillayer depths of supplemental irrigation were designed as0-40cm and0-140cm.The relativesoil moisture content in the designed layer depths were70%and75%. To compare andcontrast, no irrigation (W0) and irrigated60mm at jointing and anthesis (W1) were designed,respectively.1Effects of tillage on soil hardnessDeep loosening decreased bulk density of the soil layer20-30cm, indicated that deeploosening breaks the plough layer and promoted root deep growth. Treatment G3decreasedbulk density of the soil layer0-5cm and increased5-10cm layer, Created a good environmentfor seed germination. However, rolling caused the soil to harden by increased bulk densityof0-10cm layer dramatically when the soil moisture content was90%.2Effects of tillage and soil moisture on water consumption characteristics of wheat2.1Effects of tillage on water consumption characteristics of wheatDeep loosening increased the percentage of precipitation to total water consumption andthe absorption of soil water from jointing to anthesis, which indicated that deep loosening wasbeneficial to improve the water consumption in the late growth period. The treatment G3obtained the highest percentage of precipitation to total water consumption, increased thewater consumption、soil water consumption and its water consumption amount fromjointing to anthesis; The treatment G4and G5decreased soil water consumption amount fromjointing to anthesis, and increased absorption of soil water form anthesis to maturity, indicated that it was benefical to improve absorption of soil water when grain filling.2.2Effects of soil moisture on water consumption characteristics of wheatUnder the same condition of tillage, the treatment W0had the lowest water consumptionamount after anthesis, increased the percentage to total water consumption of earlier growthstage. Under the treatment G1and the same relative moisture content, the soil layer depths insupplemental irrigation0-40cm increased the water consumption percentage from jointing toanthesis. Under the treatment G2、G3, when the relative moisture content was70%, thetreatment of soil layer depths in supplemental irrigation was0-40cm obtained the highestwater consumption amount, increased the percentage of irrigation to total water consumption,and decreased the percentage of soil water consumption to total water consumption; When therelative moisture content was75%, the treatment of soil layer depths in supplementalirrigation was0-140cm obtained the highest total water consumption.3Effects of tillage and soil moisture on dry matter accumulation and distribution of wheat3.1Effects of tillage on dry matter accumulation and distribution of wheatDeep loosening increased the accumulation of dry matter at anthesis and maturity; underthe treatment W0, the treatment G3and G4was beneficial to promote the dry matter ofmaturity distribute to grain. Under the treatment W2, the treatment G3promoted the drymatter of maturity distribute to spike axis and glume, the treatment G2was beneficial topromote the dry matter of maturity distribute to grain. Under the treatment W3, the grain drymatter of the treatment G3is higher than the treatment G2, indicated that the treatment G3was beneficial to distribute the dry matter to grain.3.2Effects of soil moisture on dry matter accumulation and distribution of wheatUnder the same tillage, the treatment W0obtained the lowest dry matter accumulation.Under the same relative moisture content, the soil layer depths in supplemental irrigation0-40cm increased the dry matter distribute to grain and assimilation amount after anthesis.With the relative moisture content70%, the depth has no effects on assimilation beforeanthesis transport to grain. With the relative moisture content75%, the soil layer depths insupplemental irrigation0-140cm was beneficial to assimilation before anthesis transport tograin. The treatment W3obtained the highest accumulation of dry matter and grain, indicatedthat the relative moisture content is75%under the depth0-40cm promoted the accumulationof grain from anthesis to maturity. 4Effects of tillage and soil moisture on soil nitrate nitrogen and nitrogen accumulation anddistribution in wheat4.1Effects of tillage on soil nitrate nitrogen and nitrogen accumulation and distribution inwheatDeep loosening promoted the uptake rate of soil nitrate nitrogen in0-60cm soil profile, thetreatment G3and G4also were benefit for the absorb of soil nitrate nitrogen in top soil profile.With the same soil moisture, deep loosening boosted nitrogen accumulation at maturity.Nitrogen accumulation amounts at maturity were increased under the treatment G3and G4,moreover, nitrogen distribution from vegetative organs to grain at maturity and nitrogentranslocation from vegetative organs to grain were furthered in the treatment G3.4.2Effects of soil moisture on soil nitrate nitrogen and nitrogen accumulation and distributionin wheatWith the same tillage, soil nitrate nitrogen in0-60cm soil profile was used preferably underthe treatment W3. Nitrogen accumulation amounts in grain, spike axis and glume, stem andleaf sheath and leaf at maturity were increased in W3, whose nitrogen accumulation invegetative organs at anthesis and maturity was higher than that of other irrigation treatments.It showed that nitrogen accumulation in vegetative organs at anthesis and maturity wasobviously enhanced under0-40cm soil profile supplemental irrigation with soil moisture at75%of field capacity.5Effects of tillage and soil moisture on grain yield and water use efficiency in wheat5.1Effects of tillage on grain yield and water use efficiency in wheatDeep loosening enhanced grain yield and water use efficiency in the same soil moisturetreatment. Under the treatment W0, grain yield and water use efficiency under the treatmentG3and G4were larger than those of other treatments. In the same soil moisture, grain yieldunder the treatment G3was increased, irrigation benefit was higher than that of the treatmentG4. In this research, the treatment G3was the optimum tillage on high yield and water-savingin wheat.5.2Effects of soil moisture on grain yield and water use efficiency in wheatIn the same tillage, grain yield under the treatment W2and W3was larger than that of thetreatment G4and G5, which showed that grain yield was increased under0-40cm soil profile supplemental irrigation, as the highest grain yield and water use efficiency in the treatmentW3. Irrigation benefit in the treatment W3exceeded other treatments. In this research,0-40cm soil profile was the optimum soil depth for supplemental irrigation.