Effects Of Planting Density On Yield And Quality Of Weilong 169 Wheat

Wheat is the main grain crop in China.and in order to improve the yield and quality of wheat,it is necessary to choose high quality and high yielding varieties.Weilong 169 wheat is a new variety of high quality and strong wheat suitable for planting in the Guanzhong irrigation area.To further understand its growth and development characteristics,improve its high-quality and high-yielding supporting cultivation technology,and speed up its application,we conducted a study on its agronomic traits,population structure,individual quality and dry matter transport characteristics,seed filling characteristics,lodging resistance,yield and quality under the density of D1(2.4×10~6 plants/hm~2),D2(3.0×10~6 plants/hm~2),D3(3.6×10~6plants/hm~2),D4(4.2×10~6plants/hm~2),D5(4.8×10~6plants/hm~2),D6(5.4×10~6plants/hm~2),D7(6.0×10~6 plants/hm~2)at the Agricultural Station 1,North Campus of Northwest A&F University from 2021 to 2022..The results showed that:1.Planting density had significant effect on individual agronomic traits of Weilong 169wheat.With increasing planting density,plant height and leaf age increased,while tillers and secondary roots decreased.Height of center of gravity of the plant increased and the lodging resistance decreased.The plant height increased by 4.04cm-10.52cm,an increase of 5.7%to14.7%.Leaf age increased by 0.24-1.58;In overwintering stage,greening stage and jointing stage,grade I tillers decreased by 0.17 per plant-1.37 per plant,0 per plant-0.6 per plant and0.3 per plant-1.6 per plant,respectively.Secondary rooting decreased by 0.2 roots per plant-5.8 roots per plant,0.9%-26.7%.Height of center of gravity of the plant of wheat was moved up by 0.8cm to 6.56cm,and the strength of the first and second internodes at the base of wheat decreased by 56.24Kpa to 275.68Kpa and 30.46Kpa to 183.7Kpa,respectively.Internode length increased by 0.64cm-1.96cm and 0.26cm-1.32cm,respectively.Internode wall thickness decreased by 0.08mm-0.43mm and 0.05mm-0.43mm,respectively.Internode linear density decreased by 0.002g/cm-0.025g/cm and 0.006g/cm-0.024g/cm,respectively.Lodging resistance index decreased by 0.03-0.43 and 0.01-0.33,respectively.2.Planting density had significant effects on dry matter accumulation and grouting characteristics of Weilong 169 wheat.With increasing planting density and the advance of growth process,dry matter accumulation per plant decreased from 0.002g～0.034g in wintering stage to 4.06g～6.89g in mature stage.From wintering stage to mature stage,there was an increase in dry matter accumulation from 47.64 kg/hm~2 to 515.15 kg/hm~2 to 3986.67 kg/hm~2to 17237.33 kg/hm~2,respectively.After anthesis stage,the dry matter accumulation of plant gradually transported to the grain of spike.Stem+sheaths,leaf and spike,decreased by 31.7%,10.0%and-41.7%respectively from anthesis stage to maturity stage.During the whole grain filling process,the grain filling rate of low planting density was lower than that of high planting density within 20 days and 35-40 days after anthesis,and the grain filling rate of high planting density was lower than that of low planting density within 20-35 days after anthesis.The seed filling rate showed a"slow-fast-slow"growth dynamic at different densities,with the dry weight of 1,000 grains at a higher level at lower densities.3.Planting density had a significant effect on the yield of Weilong 169 wheat.Although the increase of planting density resulted in the increase of panicle number by 0.08×10~4spikes/hm~2-2.63×10~4 spikes/hm~2,the grain number per panicle and 1000-grain weight of wheat decreased significantly by 1.73-6.87 grains and 0.45-1.6g,respectively.In the range of 2.4×10~6 plants/hm~2 to 6.0×10~6 plants/hm~2,the yield showed a 2.9%to 42.73%increase as the planting density increased.The highest yield of 9381.38kg/hm~2 was achieved at a planting density of 4.2×10~6 plants/hm~2.When the target yield was 8250kg/hm~2-9343.64kg/hm~2,the planting density was 3.13×10~6 plants/hm~2-5.49×10~6 plants/hm~2.4.Planting density had significant effects on some quality characters of Weilong 169wheat,including test weight,drawing area,tensile resistance,ductility and maximum tensile resistance.With increasing planting density,test weight increased first and then decreased,reaching a maximum of 829.13g/L at 5.4×10~6 plants/hm~2.The minimum tensile resistance and maximum ductility of 5.4×10~6 plants/hm~2 were 292.19E.U and 135.1mm,respectively.In this experiment,the wheat quality was better in 4.8×10~6 plants/hm~2-6.0×10~6 plants/hm~2.In conclusion,the planting density of Weilong 169 is 3.31×10~6 plants/hm~2 to 5.65×10~6plants/hm2 for high yield,4.8×10~6 plants/hm~2 to 6.0×10~6plants/hm~2 for high quality,and4.8×10~6 plants/hm~2 for high yield and high quality in Guanzhong,Shaanxi Province and the same ecological type areas with late sowing at the right time.The planting density of high yielding and high quality is 4.8×10~6 plants/hm~2-5.49×10~6 plants/hm~2.