The Study On The Effect Of Sowing Date And Density On The High Yield Mechanism Of Denghai 618

High density planting is one of the most important way to improve corn yield and to controleasily,application of plant type is compact,yield potential of maize hybrid is the basis of yield.The misjudgement of maize physiological mature standards due to farmers as well as the intrinsic harvest conformity habits for years,cause the corn moisture content at harvest on the high side,production is reduced,so the maize production in urgent need of early maturity and high yield varieties.The maize breeding denghai 618,the precocious high-yielding,resistance were created in shandong laizhou summer sowing corn 16576.5 kg/hm2 and genetic stability in xinjiang farms spring sowing corn record high of 22676.1 kg/hm2.This study was conducted in the 16 th trial ground of shandong denghai seed industry co.,LTD.in 2014-2015.Using denghai618,zhengdan958 varieties as materials.The experiment was carried out in five different sowing date and six different density,so as to explore the high-yield characters of new variety denghai 618,research on the mechanism of early maturity,resistant to close for corn breeding for high yield and provide theoretical guidance and technical support.The main results as follows: 1 Effects of sowing date and density on yield,as well as its components of maize of Denghai 618This study shows that the sowing period,density as well as the two interaction of Denghai 618 and Zhengdan 958 yield,1000 grain weight,panicle number,panicle weight had significant difference,2 varieties showed that yield firstly increased and then decreased with the delay of sowing date.The yield of Denghai 618 increased with the density increased,the yield of Zhengdan 958 increased firstly and then decreased with the increase of density.Denghai 618 in June 25 sowing date D6 density under the combination of the highest yield,with the sowing date postponed 1000 showed first increased and then decreased with the sowing period,showed a decreasing trend with the increase ofdensity.Denghai 618 can achieve the best level under the yield and yield components on June 25 in D6 sowing density.2 Effects of sowing date and density on Denghai 618 dry matter accumulation and distributionDifferent sowing date and density of single plant dry matter accumulation showed a slow growth trend soon after the first,with the delay of sowing date,the dry matter accumulation per plant decreased,and with the increase in the density of dry matter accumulation decreased,Denghai 618 with the delay of sowing date,plant dry matter did not change significantly in D1.,D2,D3,dry matter accumulation than Zhengdan 958,in the D5 D4 density Denghai 618 per plant at maturity stage,D6 density,dry matter accumulation was higher than that of Zhengdan 958,Denghai 618 population growth early dry matter accumulation rate of growth with the delay of sowing date significantly accelerated Denghai 618 per plant at maturity stage,and groups the largest group of volume cumulant also showed a certain increasing trend.In June 25,Denghai 618 sowing date D6 population dry matter accumulation.The highest Denghai 618 harvest in June 25 th D4 density index showed the law that the highest seed > stem > leaf dry matter allocation proportion of maturity.3 Effects of sowing date and density on lodging resistance and plant traits Denghai 618The root length showed with delayed sowing and gradually decreased with the increase of density gradually decreased.Denghai 618 root length in different sowing densities were longer than that of Zhengdan 958 this study shows that the flexural strength,anti thrust showed with delayed sowing and gradually decreased with the increase of density and decreasing trend.While tensile forces are not consistent,the biggest 25 month Denghai 6186 sowing date tensile force,tensile strength decreasesgradually with the increase of density.Denghai 618 anti thrust,resistance in different sowing densities were higher than that of Zhengdan 958 in June 25 th D1 Denghai 618 tensile force density showed the greatest.4 Effects of sowing date and density on Grain Filling Characteristics and Denghai 618 dehydration characteristicsThe Tmax,Gmax and RO were gradually shortened with the delay of sowing time,changes of Wmax showed first increased and then decreased,the grain filling period of active P changed not obviously with the increasing of density,Tmax,Wmax,Gmax,RO,P showed changes gradually decreased,Denghai 618 Tmax,Wmax Gmax,RO,is not obvious difference,affected less by sowing date.Denghai 618 in D4 density reached the maximum value,Denghai 618 had a relatively short growth period can quickly enter the active period of the maximum grain filling rate,maximum grain filling rate,grain filling accumulation starting potential high,active grain filling period is short,in June 25 day period and the density of D4 grouting under the optimal parameters,25 June sowing date is more conducive to Denghai 618 grouting.With delayed grain moisture showed a trend of first increase and then decrease the sowing date,with the increase of the density,harvest grain moisture showed a gradually increasing trend,the average rate of dehydration Show a gradually decreasing trend.5 Effects of sowing date and planting density on Photosynthetic Characteristics of Denghai 618Lai was first increased and then decreased,the flowering period reaches the maximum value.Flowering stage to milk stage(30d after flowering)to maintain a high level,late sowing significantly decreased Lai,suitable sowing date can form high Lai density,increase leaf area index increased,combined with other factors of Deng Hai-6 in June 5th 618 month 25 day D6 density to form larger leaf area index.Photosynthetic rate of maize ear Ye Jingguang showed decreased with the delay of sowing time,and decreases with the increase of density,and with the advance of thegrowth period,gradually reduce,Deng Hai 618 effects of sowing time and density is not obvious,in late sowing and high density conditions is conducive to photosynthesis.With the delay of sowing date of ear leaf photochemical efficiency(fv/fm)showed a decreasing trend,with the increasing of the density decreased,and with the advance of the growth period decreased.In Deng Hai618 still have relatively high density High light energy conversion efficiency,but also with the delay of sowing time and the increase of density is affected by the smaller.6 Effects of sowing date and density on the growth period and sunlight and temperature production efficiency of Denghai 618From May 25 th to July 5th sowing of corn,the whole growth period of the same variety of temperature difference,Denghai 618 during the whole growth period required for the June 25 day period of the lowest temperature,the highest for the May 25 day period,respectively,2740 and 2845?·d,before days decreased with the delay of sowing date,with the density the increase did not change significantly.While the accumulated temperature showed with the delay of sowing time and decreased with the increase of density did not change significantly.The days after flowering with delayed sowing date appeared increasing trend,with the increase of density did not change significantly after anthesis accumulated temperature showed increased with the sowing date postponed trend,with the increase of density did not change significantly,The growth period of Denghai 618 was shorter 6-8 days than that of Zhengdan 958,the required temperature was less than that of Zhengdan 958.Denghai 618 situation still has high and energy efficiencyin late sowing time and high density,the sunlight and temperature production efficiency of denghai 618 was better than zhengdan 958 in the same condition.