Effect Of Sow Dates And Densities On Wheat Growth Characteristics And Yield

Sowing date, density are factors more easily to control in wheat cultivation, but they plays a critical influence in wheat growth,in different varieties and cultural environment have various. We adopt optimum design of sowing date and density in experiment.Study influence on Shanmai159 and Xinong9871 of yield traits with different sowing and density.Intent to select the best sowing date and density to provide a theoretical reference..The results showed that sowing date and planting density influenced the length of growth progress, further affecting to wheat groups and individual development. They will affect the wheat root growth, plant height and development of Spike, the ultimate impact to wheat production.(1) Sowing and planting density affect the process of wheat growth,and density had little effect . Sowing the later emergence of the longer time required, the number of days required for germination with the delay of sowing date increased. Sowing at october 1,the days of emergence was 7 days,and sowing exceed october 18 requiring 10 days.Later sowing delayed progress of wheat growth, but it reduced the growth progress by 19 days.(2)Sowing date and planting density significantly effected on the size of the two wheat groups .Two treatments of wheat that sown at 1 October the total number of stems in the winter and before the jointing stage were significantly higher than the late sowing . Before winter the number of stems per plant in early sowing was significantly greater than the late sowing. With the temperatures rising,and soil thawing in spring, the number of tiller faster increase, early sowing and late sowing reduced the gap between the number of stems per plant. The number of stems per plant between the two treatments at 11 October and 18 October was no significant difference with 1 October .25 October the total number of stems per plant stem number is still small.(3) The number of secondary roots increased with the growth process. Secondary roots at different sowing dates and densities showing a decrease with delayed sowing, with the density increasing trend of improvement. The number of secondary root of high density is greater than low density in early sowing, while low-density is greater than high-density treatment. Before winter Shanmai159 and Xinong9871, on 1 October density 2.7 million / hm2 are get the largest number of secondary roots, significantly higher than other treatments. 25 October density of 120 million / hm2 was the lowest number of secondary roots. The early sowing maintained the advantages of secondary roots, but with the growth process, in jointing stage and filling the gap between the number of secondary roots decreasing.(4) Dry matter accumulation performance decreased with the sowing delayed. Before the jointing stage dry matter accumulation relatively large difference between treatments, the differences became smaller in filling stage. Early sowing cases, low density accumulate moer dry matter than high density. In late sowing high density accumulate more dry matter than low density.(5) With the delay of sowing ,stems into the spikes fall, with the lower planting density decreased. Shanmai159 and Xinong9871 in October 1, density of 2.7million / hm2 into a spike great and the 25 October sowing density was 1.2 million / hm2 is less. As the planting density of wheat grain increased the number of reduced, with the delay of sowing date also appears on the rise. With this study, grain weight of wheat sowing increased the delay of the first down, with the reduction in planting density reduced. Shaanxi wheat grain weight for the 159 largest of the 11 October broadcast seeding density 1.8 million / hm2, the grain weight 44.7g. Wesfarmers 9871 grain weight is the biggest deal for the 25 October density 2.25 million / hm2 when the grain weight is 45.4g. Wheat yield and sowing date, density close. Wheat showing a decrease with the delay of sowing date, with the decrease of the density decline. Shanmai 159 and wheat varieties Xinong 9871 two different sowing dates on yield consistent performance and density on yield response different. Shanmai159 sowing October 1ofdensity 120 million / hm2 when the highest yield, the actual yield 8100kg/hm2. Xinong9871,1October sowing density of 2.7 million / hm2 when the highest yield for the production 9886 kg / hm2.From sowing to emergence the accumulated temperature is constantly, with the sowing delayed the temperature decreased gradually,wheat need more time to germinate, early sowing have a sufficient temperature condition. Early sowing favorable of formate valid spike, and late sowing need to increase the planting density to increased spike. Reduce the planting density are more favorable on formation wheat grain number. Wheat grain-weight with the increase of the delayed sowing after the first drop, with the reduce density is decrease, proper planting conducive to the formation of a higher grain-weight. Early sowing favorable of increase wheat yield, high density favorable of obtain a great production, especial when late sowing, need to increase the number of main stem into spike to compensation lack tiller, relying on the main stem into spike to increase production...