Effects Of Different Sowing Methods And Densities On Population Quality And Yield Of Drip Irrigation Winter Wheat

From 2018 to 2019,the field plot experiment was carried out in the net room of agricultural experimental station of Tarim university.The winter wheat Handan 5316 was used as the test variety,and the two-factor split plot experiment design was adopted.The main area was planted in three ways:row sowing?B1?,hole sowing?B2?and uniform sowing?B3?.The sub-area was divided into four density Treatments,namely M1(315×10⁴grain·hm^-2)M2(510×10⁴grain·hm^-2)M3(705×10⁴grain·hm^-2)and M4(900×10⁴grain·hm^-2).the dynamic changes of population and individual growth,physiological characteristics,population environment and yield were observed in different sowing methods and density amount combination plot,the best combination of high quality and high yield was selected,In order to further study the drip irrigation winter wheat production behavior water saving,reasonable planting technology improvement to provide a certain theoretical basis.The specific test results are as follows:Under the condition of B3,winter wheat under drip irrigation had the most tillers and the largest total stem number before winter,but the quality of wheat seedling was poor;the growth of tiller in theB1and B2group was stable,and the earbearing tiller percentage was 15.38%and 57.69%higher than that of B3respectively,during the milk ripening stage,the wheat plant height was the highest under the combination of B2 and M3 treatment,it`s86.4cm,The final plant height of B2 was 2.10%and 4.42%higher than that of B1 and B3,and the appropriate density increased significantly with the density.During heading period,LAI reaches the maximum value,The early LAI of B1 and B3 increased rapidly,B2 is slowly,performance B3>B1>B2;Within the appropriate range,LAI has significant positive density effect,The average blade inclination of B2 and M3 treatment combination is the largest,followed by B2 and M4 treatment combination,the average blade inclination of B2 is larger than that of B3 and B1.Under the combination of B1 and M3,the maximum light interception rate was 75.26%,B1 is higher than B2 and B3 in the whole growth period 9.36%and 4.18%;And within the appropriate range,the density increases significantly.The total dry weight of the overground part of a single plant was in line with the S curve,The combination of B2 and M1 from milk ripening stage to wax ripening stage showed the greatest performance,it`s3.81g·plant^-1,the second is the combination of B2 and M2,is 3.73g·plant^-1,and B2 is 6.97%and 4.78%higher than B1 and B3,the dry matter accumulation decreases with the increase of density.Stem resistance index and central height change is the opposite,the lodging resistance index of B2 is higher than that of B3and B1 respectively 0.71%and 9.30%,it has a negative density effect.During task-filling period,the photosynthetic efficiency of wheat was at its maximum.During filling period,the net photosynthetic rate of flag leaf had a peak value at 14:00 and 18:00,and the maximum value at 18:00,and the lunch break occurred at 16:00,B3 and low density napping were more severe.The photosynthetic rate of B1 and B2 was higher than B3,among them,the average SPAD value,Pn,Gs and Tr of B2 are the highest,Ci is minimum,and within a certain range,there is a negative density effect.The average SPAD Pn Gs and Tr of B2M1 were the largest,followed by B2M2,the Ci of B2M2 was the smallest and the photosynthetic efficiency was the best.From heading to filling stage,the population environment of wheat was the most likely to deteriorate,and the relative humidity of canopy in the flowering stage showed a Trend of decreasing first and then increasing,with the highest at 16:00 around 8:00 and the lowest at 16:00.The sowing method showedB1>B2>B3,with a positive density effect within the appropriate density range.On the contrary,the canopy temperature is the highest at 14:00,and the sowing method is B3>B2>B1.Within the appropriate density range,there is a negative density effect.The average yield of B2 was 3.63%higher than that of B3 B1,and the maximum yield of B2M2 was8 329.4 kg·hm^-2,Under the same seeding method,the number of spikelet per thousand grain weight and the number of spikelet per thousand grain weight decreased significantly with the density.The number of1000-grain weight spikelets and the number of panicle grains were the highest under B2M1 treatment,which were 45.06g,20.92,14.38cm and 31.9 ears,respectively,followed by B2M2 treatment,which was44.96g,20.56,14.18cm and 31.75 ears,respectively.The average 1000-seed weight was B2>B1>B3 under the three sowing methods.Spikelet number spike length and spike grain number were shown as B2>B3>B1.Under different density treatments,1000-grain weight,spikelet number,spike length and spike grain number decreased with the increase of density;From the perspective of the influence degree CV of sowing method and density on the yield,the density?4.63%?was greater than that of sowing method?3.37%?,indicating that the density had a greater influence on the yield.The optimal treatment combination selected in this experiment was B2M2 treatment,and the basic seedling number was 349.50×10⁴·hm^-2,1.66 tillers/plant;The average central height is about 37cm;The leaf area indexes of the population at booting stage and heading stage and filling stage were 4.60,7.62 and5.31,respectively,The leaf inclination angle from jointing stage to booting stage is about 63,the average light interception rate was 55.3%.The total dry weight of the above ground part of a single plant reached3.49 g·plant^-11 at the milk stage,he average SPAD value was 49.53,The net photosynthetic rate at jointing stage,booting stage and filling stage were 20.68?mol·m^-2·s^-1,18.84?mol·m^-2·s^-11 and25.06?mol·m^-2·s^-1,respectively;the average canopy temperature and relative humidity during the whole growth period were 23.04?and 50.76%,respectively.The average stem resistance index was 1.53N·cm^-1;The number of spikelet was 20.56/plant and the number of harvested spikelet was583.51×10⁴·hm^-2,The 1000-grain weight was 44.96g,And the number of panicle grains was31.75/plant.Under the above conditions,the yield of B2M2 treatment was the best,which was 8329.4kg/hm².