Study On Adaptability Of Different Rice Varieties To Dry Direct Seeding Cultivation

Rice is one of the main food crops for humanity,and in recent years researchers have shifted their focus from increasing yields to improving quality.In this paper,the adaptability of the four rice varieties to dry direct cultivation was studied through the yield,yield composition factors,appearance quality,taste quality,processing quality,texture characteristics of rice,and tasting experimental indicators of the four mainly cultivated highquality varieties in Tianjin.The results show that the adaptability of four varieties to dry direct seeding is Jinjing518 > Jinchuan 1 > Jinyujing 22 > Jinyuan E28 according to the yield and its component factors.The influence degree of yield components on yield is as follows: Grains per panicle >1000 grain weight > Effective panicles per unit area > Seed setting rate.By comparing the rice quality of dry direct seeding and machine transplanting of four different high-quality rice varieties between Gaotuo village and corn improved seed farm in2020,the overall rice quality of corn improved seed farm is slightly higher than that of Gaotuo village,indicating that although the corn improved seed farm uses the same field management as Gaotuo village,the soil and water quality conditions of corn improved seed farm are better than that of Gaotuo village,and the rice growth condition is better.Strong adaptability is not only the improvement of numerical value.This experiment integrates the data of the two sites,and takes whether the two models have significant differences,the level of numerical value and the stability of the two site indicators as the standard to measure the adaptability of dry direct seeding cultivation.According to the indicators of sperm yield and roughness rate,the data of the two places are comprehensively analyzed under the condition of dry direct seeding.Through the indicators of roughness rate and sperm yield,the adaptability of the four varieties to dry direct seeding is Jinjing 518 > Jinyuan E28 > Jinchuan1 > Jinyujing 22,and the sperm yield of Jinyuan E28 is significantly higher than that of machine transplanting.The whole rice rate and broken rice rate showed that the adaptability of the four varieties to dry direct seeding was Jinyujing 22 > Jinchuan 1 > Jinjing 518 >Jinyuan E28,and the whole rice rate of jinyujing 22 and Jinjing 518 was significantly improved by dry direct seeding.According to the grain type index,the degree of brown rice quality under dry direct seeding is Jinchuan 1 > Jinjing 518 > Jinyujing 22 > Jinyuan E28.According to the grain type index,the degree of wear-resistant quality of milled rice under dry direct seeding is Jinyuan E28 > Jinjing 518 > Jinchuan 1> Jinyujing 22,and the grain type of Jinyuan E28 is significantly better than machine transplanting under dry direct seeding.According to the index of bad white grain rate,the adaptability of the four varieties to dry direct seeding cultivation is Jinyujing 22 > Jinchuan 1 > Jinyuan E28 > Jinjing 518.According to the taste quality index of rice,the quality of four varieties is Jinchuan 1 >Jinyujing 22 > Jinyuan E28 > Jinjing 518.According to the index of rice taste value,the adaptability of four varieties to dry direct seeding is Jinyujing 22 > Jinchuan 1 > Jinyuan E28 > Jinjing 518.According to the taste,the result is Jinchuan 1 > Jinyujing 22 > Jinyuan E28 > Jinjing 518.According to the appearance quality,processing quality,eating quality,rice texture and taste experimental indexes,the adaptability of the four varieties to dry direct seeding cultivation is: Jinchuan 1 > Jinyujing 22 > Jinyuan E28 > Jinjing 518.The effects of different milling degrees on the appearance quality,physical and chemical properties and RVA gelatinization characteristics of four varieties of rice were studied.The indexes of the same milling degree of four varieties of rice under the conditions of dry direct seeding and machine transplanting were compared.According to the appearance quality results,the rice with different milling degrees that meet the standard are selected as follows:Jinchuan 1（CY）R1,R2 and R3,Jinchuan No.1（ZB）R1,R2 and R3,Jinyuan E28（CY）R1and R2,Jinyuan E28（ZB）R1 and R2,Jinyujing 22（CY）R1,R2,R3 and R4,Jinyujing 22（ZB）R1,R2,R3 and R4,Jinjing 518（CY）R1,R2 and R3,Jinjing 518（ZB）R1,R2 and R3.Then,the contents of protein and amylose were compared and analyzed（Fig.4-6,Fig.4-7,Table 4-2 and Table 4-3）,and the rice with different milling degrees meeting the standard were selected,including Jinchuan 1（CY）R3,Jinchuan No.1（ZB）R3,Jinyuan E28（CY）R2,Jinyuan E28（ZB）R2,Jinyujing 22（ZB）R4,Jinyujing 22（CY）R4,Jinjing 518（CY）R3 and Jinjing 518（ZB）R3.Then,the RVA gelatinization characteristics of rice flour were tested.According to the three important indexes affecting rice quality: maximum viscosity,disintegration value and alkali elimination value,the rice with the highest viscosity,the lowest alkali elimination value and the highest disintegration value was selected.The selection results were: Jinchuan 1（CY）R2,Jinchuan 1（ZB）R2,Jinyuan E28（CY）R2,Jinyuan E28（ZB）R2,Jinyujing 22（CY）R3 and Jinyujing 22（ZB）R3,Jinjing 518（CY）R3,Jinjing 518（ZB）R3.Based on the above three screening results of main influencing factors,the best grinding degrees of four varieties with different planting modes are summarized as follows: Jinchuan 1（CY）D2（10%）,Jinchuan No.1（ZB）D2（10%）,Jinyuan E28（CY）D2（10%）,Jinyuan E28（ZB）D2（10%）,Jinyujing 22（CY）D3（15%）,Jinyujing 22（ZB）D3（15%）,Jinjing 518（CY）D3（15%）,Jinjing 518（ZB）D3（15%）.Through this experiment,the correlation coefficient between milling degree and influencing factors of rice quality is obtained at the same time,The influence degree of milling degree on these indexes is as follows: Broken rice rate（0.887）= Head rice rate（-0.887）= Whiteness（0.887）> Chalky grain rate（0.867）> Peak viscosity（0.838）> Trough viscosity（0.676）> Aspect ratio（-0.627）> Amylose（0.556）> Breakdown（0.531）> Final viscosity（0.519）> Setback（-0.511）> Protein（-0.434）.The results of this study provide an important theoretical basis for the popularization of dry direct broadcast cultivation technology and the production and processing of dry direct rice varieties.