Effect Of Sowing Date On Yield And Rice Quality Of Machine Transplanted Rice In Huaibei

The test was carried out in pingming town, donghai county, jiangsu province from 2013 to 2014, taking the conventional medium japonica lianjing No.7, conventional late maturity japonica nanjing 9108, medium maturing indica-japonica hybrid rice yongyou 2640 as the experimental material. And the test was aimed at exploring the influence of different sowing period (may 21th, may 26th, may 31th, june 5th, june 10th, june 15th, june 20th) on growth period, of accumulated temperature, yield, population quality, nitrogen use efficiency and rice quality of the different varieties under the condition of wheat stubble. Therefore, the test was expected to provide theoretical and practical basis for suitable sowing period for the high-quality rice nanjing 9108 and high yield potential of yongyou 2640 in Huaibei area. The main results were as follows:(1)Along with the delayed sowing date, the whole growth period of all varieties became shorter, the amplitude reaching 15-16 days. The number of days from sowing to heading changed most and the range was 14-15 days. And the days from the sowing to heading mainly accouted for. the changes of the growth period of different sowing dates.(2) Along with the delayed sowing date, accumulated temperature and sunshine hours during the whole growth period in different varieties all decreased. The differences of accumulated temperature in the whole growth period with various varieties under different sowing date were mainly embodied at that in the period from sowing to heading stage, while differences became smaller after heading. And the temperature utilization rate decreased significantly as the sowing date delayed.(3) Along with the delayed sowing date, the yield of different varieties decreased significantly, and the yield of the first sowing date (May 21st) was highest. And the yield components all decreased with the delay of sowing date. Under the same sowing date, the yield of different varieties and its components were different. before June 15th and yield were shown to Yongyou 2640 yield was the highest, followed by Nanjing 9108, Lianjing No.7 is slightly lower. Before June 10, Yongyou 2640 mu 650kg above, Nanjing 9108 per 600kg above that June 10 before sowing date for machine in Huaibei area planting suitable sowing period; after the June 10, three varieties yield below the local average, especially Yongyou 2640 last sowing date is not mature. From the analysis of the yield structure, in the same sowing period, Nanjing 9108> lianjing No.7> yongyou 2640 in spike number, spikelets per panicle number of yongyou 2640> nanjing 9108> lianjing No.7 that medium maturing indica japonica hybrid rice than conventional Japonica Rice in the number of grains per panicle have greater advantages; seed setting rate also large differences, the overall performance of Lianjing No.7> Nanjing 9108> Yongyou 2640 that conventional rice than the hybrid rice on seed setting rate advantage; 1000 grain weight of different performance for Nanjing 9108 slightly higher than Lianjing No.7, Yongyou 2640 minimum. Of the three cultivars, Yongyou 2640 contains the highest number of spikelets, It showed that the increase of the amount of floret was the main factor of high yield.(4) Along with the delayed sowing date, the influences of different varieties under different sowing dates on stem and tiller, dry matter accumulation of population quality were different, the first sowing period (May 21) treatment of different cultivars all had the best performance, which accounted for the highest yield.(5) Along with the delayed sowing date, the amount of nitrogen uptake of different varieties decreased gradually, and the proportion of nitrogen uptake in the jointing to heading stage and heading to ripening stage in the total growing stage decreased, and the nitrogen uptake of the two stages were significantly different. The uptake of nitrogen in the whole stages were different between varieties, Embodied in yongyou 2640 was slightly higher than that of nanjing 9180 and lianjing NO.7 has lowest nitrogen uptake.(6) Along with the delayed sowing date,, rice quality of different varieties showed the same change trend, and the specific changes were as bellow:along with the delayed sowing date, the milling quality and appearance quality deteriorated, and straight chain starch content decreased, while protein content increased, beside, peak viscosity, hot viscosity, breakdown value and final viscosity all decreased as the sowing date delayed while the gelatinization temperature and subtractive value raised. And it could be concluded that, early sowing is beneficial for improving the rice milling quality, appearance quality and cooking and eating quality in huaibei area, while it is not conducive to the nutritional quality of rice. Under the same sowing date, milling quality of nanjing9018 had better performance better than lianjing NO.7 and yongyou 2640, and appearance quality of lianjing NO.7 was better than nanjing9018 and yongyou 2640.Based on the above results, we can conclude that, the early sowing in huaibei region is the most important method to achieve the production target for coordination of high yield, high quality and safety. Moreover, under the condition of early sowing in Huaibei area, we can choose the high-quality rice variety nanjing 9108 and the high yield variety yongyou 2640.