Effects Of Nitrogen Management On Population Quality And Grain Quality Of Bowl Seeding Rice By Machine Transplantation

To explore effects of nitrogen management on population quality and grain quality of bowl seeding rice by machine transplantation,the tests began in Lujiang County Guohe Modern Agricultural Demonstration Garden（Guohe Town Bei Wei Country）in 2014-2015 years.Yongyou 538 and Zhendao 18 were used for materials to study the differences under different nitrogen management modes of rice yield formation characteristics,in physiological and ecological characteristics and quality characteristics,and clear suitable nitrogen management modes for bowl seeding rice by machine transplantation lay the theoretical foundation for high yield and high quality cultivation of rice.The test main results were as follows:1.T3 treatment’s（basal dressing:tillering:promoting fertilizers:Paul fertilizers=4:2:2:2）the theoretical yield（13.33-14.22 t/hm²）and the actual output（10.96-11.24 t/hm²）were the highest,and the difference with other treatments was significantly higher（p<0.05）under different proportions of basal dressing and topdressing.From the yield factors,the difference of effective spikes with other treatments was significantly higher（p<0.05）;there was genotypic differences of grains per spike in treatments between changes,T1 treatment of Yongyou 538 was the largest,Zhendao 18’s was the T3 treatment;seed rate showed CK>T3>T4>T2>T1;grain weight difference was small in different treatments.Whole growth period,SPAD values showed a single peak curve,heading maximized.In the heading,SPAD values showed T3>T4>T2>T1>CK,SPAD value of T3 higher14.92%-21.68%than CK.Heading,each treatment stomatal conductance and transpiration rate and intracellular CO₂ concentration and had a similar trend with Photosynthetic Rate of flag leaves the maximum T3 treatment were significantly higher than T4,T2,T1 and CK（p<0.05）.In addition to CK,the spike rate of T3 tillers was highest（60.07%-62.12%）,a significant difference between treatments（p<0.05）.Late growth T3 treatment organics tend to allocate more to the leaf、sheath and Ear,while CK organics is distributed more to stem and sheath organs.Maturity T3 dry matter accumulation was maximum（14.54-17.41t/hm²）,CK was the lowest（6.58-7.88 t/hm²）.With the mid-stem and sheath dry matter constantly shift to spike,the lodging resistance of rice was weakened.Finally the average lodging index of T3 treatment was lowest,T4 followed,T1 worst,and T3 treatment lodging resistance was highest.From the beginning of tillering,leaf area index of each treatment gradually increased with the forward of growth,heading to the maximum;the late growth stage,each treatment leaf area index began to decline,T1 decline fastest,T3decline slowest.T3’s nitrogen absorption and utilization efficiency,agronomic efficiency,physiological efficiency and partial productivity nitrogen were significantly higher than T4,T2 and T1 treatments（p<0.05）.T3’s nitrogen absorption and utilization efficiency was48.33%-56.33%,compared with the average nitrogen absorption and utilization efficiency is improved by 25.18%-61.10%.T3 and T4 treatment had better quality than others,their milled rice rate was68.96%-69.90%,chalkiness 2.13%-6.36%,amylose content of 14.20%-15.50%,gel consistency 65.1-80.1mm,milling quality meet the national standard level 1,the appearance and nutrition eating quality were 2-3 standard.2.D3 treatment（down 4 leaf age）the theoretical yield（13.26-13.41 t/hm²）and actual yield（11.12-11.29 t/hm²）were higher than others under topdressing of different leaf ages,and the difference was significant（p<0.05）.Different leaf ages topdressing,the spike rate of D2 and D3 were higher（59.38%-64.06%）than others,but D2 treatment effective spikes was less.Maturity T3 dry matter accumulation was the largest,CK’s was the lowest.From the beginning of tillering,leaf area index of each treatment gradually increased with the growth of forward,heading to the maximum;the late growth stage,each treated leaf area index began to decline,D4 decline fastest,D3 decline slowest.While a certain amount of nitrogen,the basal dressing and topdressing of nitrogen is not the same,basal nitrogen:tillering:promoting fertilizers:Paul fertilizers=4:2:2:2 can effectively control pre ineffective tillers,increase tillers rate;At the same time,ensure nutrient supply of the heeding stage,help improve seed rate and rice quality,increase rice production.While a certain basal dressing and topdressing of nitrogen,dressing nitrogen at down 4 leaf,benefit to construction of high-yielding rice groups and organic matter transport,help to increase grain plumpness,improve the economic efficiency of nitrogen fertilizer.