Studies On Rice Yield And Quality Of Transplanting Density And Nitrogen Management In Cold Region

Longdao3 was used as test material, and all the tests were carried out at rice experimental plot and pot experimental field on Heilongjiang academy of agricultural sciences in 2008 and 2009. We combined field and pot experiments to analysis the effect of transplanting density and nitrogen management on rice appearance quality, milling quality, nutritional quality, cooking and eating quality, also yield by using variance analysis, correlation analysis, regression analysis and path analysis. We studied the relationship between quality characters and yield characters. It showed that much attention should be paid to relationships between rice taste and cultivation measures. Multi-factor experiment should be reinforced to establish productive and technical system for high quality rice production. This article is designed to provide reliable theoretical basis for high-quality rice production in cold region. The test results as follows:1.Lower or higher transplanting density presented wicked rice growth, low yield and quality. Lower density could easily lead to longer duration. It also delayed the end of effective tillering, miho and full heading stage. Higher density leaded to early maturity, lodging in late-stage and the risk of disease and insects occurrence.2. Lower or higher transplanting density was bad to rice milling quality. With the increase of planting density, chalky rice rate and chalkiness degree were both increased, the amylose content was decreased, protein content was firstly decreased and then increased gel consistency was increased, and rice taste value was firstly increased and then decreased.3. Nitrogen management significantly affected on growth and development, yield and quality of rice. The less nitrogen fertilizer was used, the earlier maturing was. With the increase of nitrogen fertilizer, spikes per unit area was increased. More nitrogen fertilizer used could lead to reluctant ripen and late-maturing. It might also increased the chance of chilling damage, as much nitrogen fertilizer used at later stage. Nitrogen fertilizer amount significantly affected effective tiller number and the maximum tiller number per hill, it played a key role on the rate of tiller panicle. Change the nitrogen management signicantly affected on effective tiller number, it has significant effect on maximum tiller number per hill. With the increase of nitrogen amount, effective tiller number and the maximum tiller number per hill was increased. Nitrogen fertilizer amount significantly affected spike number, grain number per spike, seed setting rate, 1000 grain weight and yield. Change the nitrogen management significantly affected all the yield components except seed setting rate. With the increase of nitrogen amount, grain number per spike was firstly reduced and then increased, spike number increase, 1000 grain weight was decresed, yield was incresed , and the spike number has significantly variation among treatments, 1000 grain weight and yield has significant different amount treatments. With the change of nitrogen use of per period , complex effect of yield components was presented.4. Nitrogen amount and change the nitrogen use of per period has significantly affected on each quality characters. In the different nitrogen amount situation: with the increase of nitrogen amount brown rice rate, milled rice rate and head rice rate were firstly decreased and then increased, and significant difference was found among treatments. Chalky rice rate was firstly increased and then decreased with the increase of nitrogen amount. Protein content tended to increase with the increase of nitrogen amount. With the increase of nitrogen amount, the amylose content and taste value tended to decrease. Under the change the nitrogen use of per period situation: increasing the granular fertilizer was helpful to milling quality. Appropriate panicle and granular fertilizer was better for rice appearance quality, but too much panicle and granular fertilizer would decrease the appearance quality. Appropriate granular fertilizer is better for protein content. More nitrogen dressing at late period, amylose content was firstly decreased and then increased , gel consistency was firstly increased and then decreased.