Effects Of Slow/Controlled Release Fertilizer Types And Their Application On Yield And Quality Formation Of Late Ripen Mid-season Rice

Rice cultivars of Yongyou 2640 with big panicle and Nanjing 9108 with more panicles were adopted as materials to study the effects of slow/controlled release fertilizer types and their application on the yield,nutrient uptake and utilization and quality formation of late ripen mid-season rice.Three types of slow/controlled release fertilizers(polymer-coated urea,sulfur-coated urea,and urea formaldehyde)and two fertilization methods(both slow/controlled release fertilizer and conventional urea as basal fertilizer,slow/controlled release fertilizer as basal fertilizer with conventional urea as tillering fertilizer)were conducted in field with conventional urea split fertilization as contral(CK)in 2014 and 2015 on the rice comprehensive exhibition base of Heheng.The main results were as follows:1.The application of slow/controlled release fertilizer could not increase the yield of Yongyou 2640.Big panicles and a large amount of spikelets were the advantages for Yongyou 2640 to obtain high yield.Compared with CK,most nitrogen of slow/controlled release fertilizers were released at the early and middle stage of rice,which could not supply Yongyou 2640 with enough nitrogen during stage from heading to maturity to fill the large amount of spikelets.In Nanjing 9108,rice yield of treatment with urea formaldehyde as basal fertilizer and conventional urea as tillering fertilizer was 5.2 to 5.9 percent higher than that of CK.And rice yield of treatment with polymer-coated urea as basal fertilizer and conventional urea as tillering fertilizer or treatment with both urea formaldehyde and conventional urea as basal fertilizer was similar to that of CK,while the fertilizer application frequency was decreased.Rice yields of treatments with slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer were higher than those of treatments with both slow/controlled release fertilizer and conventional urea as basal fertilizer.Rice production using different types of slow/controlled release fertilizers were urea formaldehyde>polymer-coated urea>sulfur-coated urea.Compared with the application of both slow/controlled release fertilizer and conventional urea as basal fertilizer,the application of slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer could increase the number of rice tillers effectively with a large number of panicles and a higher percentage of productive tillers.Meanwhile,the leaf area index and leaf area duration of the treatment with both slow/controlled release fertilizer and conventional urea as basal fertilizer were large,which could enhance the accumulation of dry matter and nitrogen in rice.In Nanjing 9108,compared with other types of slow/controlled release fertilizers,the reason for high yield of urea formaldehyde was that,nitrogen of urea formaldehyde could be also steadily released at the late stage of rice.Therefore,the application of urea formaldehyde as basal fertilizer and conventional urea as tillering fertilizer could not only promote tillering of rice but also maintain a high level of productive tiller and leaf area index after peak seedling stage.And the leaf area duration,dry matter accumulation after elongating and the final nitrogen use efficiency of rice were high,which were benefit for rice to obtain high yield.According to the results,it was concluded that,for rice cultivars with different characteristics of yield formation,the application of optimal type of slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer could achieve labor saving and yield increasing simultaneously in rice production.2.Under the experimental conditions,compared with CK,stage from sowing to jointing,most nitrogen of slow/controlled release fertilizers could enhance the accumulation of nitrogen and ratio of accumulation in rice,but stage from jointing to heading and heading to maturity,most nitrogen of slow/controlled release fertilizers could reduce the accumulation of nitrogen and ratio of accumulation in rice.In Nanjing 9108,stage from jointing to heading and heading to maturity,accumulation of nitrogen and ratio of accumulation in rice of treatment with polymer-coated urea as basal fertilizer and conventional urea as tillering fertilizer was similar to that of CK.The accumulation of nitrogen of treatments with slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer were higher than those of treatments with both slow/contolled release fertilizer and conventional urea as basal fertilizer.Compared with the application of both slow/controlled release fertilizer and conventional urea as basal fertilizer,the application of slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer could increase nitrogen use efficiency,agronomic nitrogen use efficiency,nitrogen grain production efficiency and SPAD value.The absorption of PK has synergistic effects with nitrogen absorption.Compared with other types of slow/controlled release fertilizers,the reason for high accumulation of nitrogen of urea formaldehyde was that,nitrogen of urea formaldehyde could be also steadily released at the late stage of rice.Thus,the absorption and utilization of NPK by rice plants were increased.3.Under the experimental conditions,compared with CK,most nitrogen of slow/controlled release fertilizers could enhance the milling quality,out quality,cooking and eting quality,as well as,could improved amylose content,peak viscosity,hot viscosity,cool viscosity,breakdown and consistence,and decrease protein content and setback.The rice quality of treatments with both slow/controlled release fertilizer and conventional urea as basal fertilizer were higher than those of treatments with slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer.Compared with the application of both slow/controlled release fertilizer and conventional urea as basal fertilizer,the application of slow/controlled release fertilizer as basal fertilizer and conventional urea as tillering fertilizer could decrease milling quality,out quality,cooking and eting quality.Compared with other types of slow/controlled release fertilizers,the reason for high yield of urea formaldehyde was that,nitrogen of urea formaldehyde could be also steadily released at the late stage of rice,but urea formaldehyde could decrease milling quality,out quality,cooking and eting quality.