Effects Of Seeding Rate And Sowing Method On Agronomic Characters,yield And Quality Of Winter Wheat Xinong 805

Wheat occupies a strategic position in grain production in China.It is of great significance to explore the influence of seeding rates and sowing methods on the yield and quality of winter wheat and to realize the matching of good seed and good methods to ensure food security.In this study,winter wheat Xinong 805 was used as the material,and random block design of two factor split zone was adopted,with seeding rate as the main area and sowing method as the secondary area.Four levels were set as follows:D1(112.5kg·hm^-2),D2(150 kg·hm^-2),D3(187.5 kg·hm^-2),and D4(225 kg·hm^-2);The sowing methods were divided into three treatments:dibbling sowing（X）,wide precise sowing（K）and drill sowing（T）.The effects on population structure,agronomic characters,spikelet seed setting characteristics,yield,and quality of winter wheat variety Xinong 805 were studied.The following main results were obtained.1.The population density of wheat increased first and then decreased with the advance of the growth period.Under the three sowing methods,the number of spikes at the basic seedling and mature stage increased significantly with the increase of the seeding rate.However,with the increase of seeding rate,the number of tillers in the greening stage still showed an increasing trend under the wide precise sowing treatment,while it showed an increasing trend first and then decreasing trend under the dibbling sowing treatment,and reached the maximum at the seeding rate of D3.The effect of sowing methods on the population density of wheat at different growth stages was as follows:drill sowing was greater than dibbling sowing and wide precise sowing,and the results were slightly different among different years.In general,the effect of the sowing method on wheat population density was smaller than the seeding rate,and the high seeding rate（D3 and D4）was beneficial to the increase of wheat population density.2.The plant height,length of sub-spike,flag leaf sheath length,and awn length under high seeding rate（D3 and D4）were larger than those under low seeding rate（D1 and D2）,but the flag leaf area and panicle length under low seeding rate was larger than those under high seeding rate.The plant height,length of sub-spike,flag leaf area and length of dibbling sowing treatment were larger than those of wide precise sowing and drill sowing treatment,while the length of flag leaf sheath of wide precise sowing treatment was larger than that of dibbling sowing and drill sowing treatment,but no significant difference was reached.3.The number of fertile spikelets and florets in different spikelet positions showed as follows:middle>upper>lower.With the increase of seeding rate,the number of florets,the number of grains,and the grain weight at different spikelet locations generally decreased at first and then increased.Dibbling sowing treatment was beneficial to the increase of spikelet seed setting rate and floret seed setting rate at different spikelet positions.Under a high seeding rate（D3,D4）,the spikelet seed setting characteristics in dibbling sowing treatment was better,especially for the seed setting of lower and upper part spikelets the effect was more obvious.4.The wheat yield of D4 treatment was significantly higher than that of other treatments,and the effect of increasing and stabilizing the yield of wide precise sowing treatment was better than that of dibbling sowing and drill sowing.Under high seeding rate（D3 and D4）,wide precise sowing and drill sowing significantly increased the number of spike,while dibbling sowing with high seeding rate（D4）and wide precise sowing with low seeding rate（D1）was beneficial to increase the number of grains per spike,and the1000-grain weight of wide precise sowing with low seeding rate（D1）was the largest.The interannual results showed that the yield of D4K treatment was 9529.11 kg·hm^-2 and10057.67 kg·hm^-2 respectively.5.The starch content of wheat grains under a high seeding rate（D3 and D4）increased significantly,while the contents of crude protein,gliadin,glutenin,wet gluten,sedimentation value,bread volume,and extensibility decreased.The effects of different sowing methods on the contents of crude protein,glutenin,wet gluten,and sedimentation value were as following:X>K>T,and the effects on the content of gliadin,bread volume and extensibility were as following:K>X>T.However,the effects of different sowing methods did not reach a significant difference level.A low amount of dibbling sowing（D1,D2）could improve the contents of crude protein,glutenin,wet gluten,and sedimentation value.A low seeding rate（D1,D2）and wide precise seeding rate could increase the content of gliadin,increase the volume of bread and improve the extensibility.A low seeding rate（D1,D2）was beneficial to increase albumin content;However,the high seeding rate（D3,D4）was more beneficial to increase the starch content of wheat grains.In conclusion,at the high seeding rate(187.5 kg·hm^-2-225 kg·hm^-2),wide precise sowing or dibbling sowing could optimize population structure,improve spikelet characters and increase yield level.However,the low seeding rate(112.5 kg·hm^-2-150 kg·hm^-2)was beneficial to the improvement of other quality except for starch content.