Study On Cultivation Regulation Of Yiled And Quality Formation Of High Quality Rice Varieties Zhuangxiangyou Baijin5

With the continuous improvement of living standards,people’s requirements for grain quality are getting higher and higher.The yield and quality of grain are mainly determined by its own genetic characteristics,and are regulated by cultivation measures such as nitrogen fertilizer,density and silicon fertilizer.Zhuangxiangyou Baijin5 is a new high-quality rice variety approved by Guangxi in 2019.In order to clarify the high-yield and high-quality cultivation conditions of Zhuangxiangyou Baijin 5 and give full play to its variety potential,this paper studies the cultivation regulation of Zhuangxiangyou Baijin5’s yield and quality formation.A field experiment was conducted in Binyang County,Nanning City,Guangxi in 2020 and 2021.Two-factor split-plot experiment was set up,with two nitrogen levels（T1,90 kg N/ha）and（T2,180 kg N/ha）in the main plot,and three transplanting densities（M1,272,000 hills/ha）,（M2,238,000 hills/ha）and（M3,206,000 hills/ha）in the secondary plot,were repeated three times in 18plots.The leaf area index,chlorophyll,nutrients,dry matter,rice yield and quality were measured.Meanwhile,in 2021,a field experiment was carried out in the experimental base of Agricultural College of Guangxi University,and a two-factor split-plot experiment was set up.Two-factor split-plot experiment was set up,with four silicon levels（Si0,0 kg Si/ha）,（Si1,90 kg Si/ha）,（Si2,180kg Si/ha）and（Si3,240 kg Si/ha）in the main plot,and two varieties of silicon fertilizer Xianyinong（K1,Si O₂>25%）and Guozhenggui（K2,Si O₂>29%）in the secondary plot,were repeated three times in 21 plots.The leaf area index,chlorophyll,nutrients,dry matter,rice yield and quality were measured.All the materials were Zhuangxiangyou Baijin 5,an indica three-line hybrid rice variety mainly cultivated in Guangxi.The research results are as follows:1)Nitrogen fertilizer and density significantly affect the growth,nutrient absorption and yield of rice.In 2020,rice sink capacity,LAI at heading stage,potassium accumulation,phosphorus accumulation at maturity stage and dry matter accumulation at maturity stage were all the highest at T2M1,while LAI at maturity stage,phosphorus accumulation at heading stage and nitrogen accumulation at T2M2.In 2021,the rice sink capacity,LAI at maturity,dry matter and nitrogen accumulation were the highest in T2M2,and the highest in leaf area index,potassium accumulation and phosphorus accumulation at heading stage in T2M1.In 2020,the highest yield was T2M1,which increased by 16.6%compared with the lowest yield.In 2021,the highest yield was T2M2,which increased by 11.9%compared with the lowest yield.High nitrogen levels and medium and high planting density can significantly promote the yield of rice.2)Sink capacity plays an important regulating role in the formation of yield.It was found that the yield was positively correlated with total dry matter accumulation and total nitrogen accumulation.There was a significant positive correlation between sink capacity and dry matter accumulation in 2020 and 2021,and a significant positive correlation between sink capacity and nitrogen accumulation in 2021.High sink capacity significantly increased rice yield by promoting dry matter and nitrogen accumulation.3)Nitrogen fertilizer and density significantly affected grain quality.High nitrogen levels can significantly reduce chalkiness rate and chalkiness degree of grain,increase the protein content and reduce the amylose content of grain,which makes the peak viscosity,through viscosity,final viscosity and breakdown viscosity in RVA spectrum decrease,while the pasting temperature and consistence viscosity.High planting density significantly increased the peak time of grain,but nitrogen levels and planting density had no significant effect on processing quality.4)Silicon fertilizer significantly appearance and taste quality of grain and moderately increased yield.The application of silicon fertilizer significantly affected the appearance and eating quality of Zhuangxiangyou Baijin 5 grain.Its chalkiness rate and chalkiness degree decreased,protein content increased slightly,and the amylose content decreased,so that the peak viscosity,through viscosity,final viscosity,breakdown viscosity and setback viscosity of grain in RVA spectrum decreased,while the pasting temperature of grain increased,which had no significant effect on the processing quality.The yield of rice increased first and then decreased with the application of silicon fertilizer,but the yield was higher than that without silicon fertilizer.Compared with the treatment without silicon fertilizer,the yield of low,medium and high silicon fertilizer treatments increased by 8.5%,6.6%and 4.0%respectively,with an average increase of 8.5%,and reached the maximum value under the treatment of Si1K2,which increased by 11.1%compared with the control.To sum up,we recommend the cultivation mode of Zhuangxiangyou Baijin5 as follows:nitrogen application of 180 kg N/ha,silicon application of 90 kg Si/ha,and density of 272,000 hills/ha or 238,000 hills/ha.