Different Effects Of Long-term And Short-term Straw Application On Quality Of Rice

Crop stalks is plentiful in our country, in recent years, a large amount of straw excesses with the improving of living standards, and the ways of the straw usage have been changed Sometimes the straw is even incinerated so as to cause atmospheric pollution and resource waste. Straw are a crucial source of nutrients in agricultural ecosystems for maintaining the ecological balance of farmland. It is a very important method for soil fertility, quality and healthy by amending straw to the soil. Straw application had been used widely in production as an important conservation farming technique now. Study on continuous effect of straw application deeply, the effect of sustainable straw application time on soil, crop yield and quality what were benefit for the technique development. This research was made in Jiangsu Taihu Area Agriculture Scientific Center. There are long-term localization experiment which set four treatments of returning whole stalks and NPK fertilizer, and short-term comparative experiment which set four treatment of returning finite stalks and two plowing methods. Study the diversity of soil physical and chemical characteristics, quality of rice and the mineral element in grain, the forming mechanism of rice quality was analyzed to define the different effects of rice quality after long-term and short-term straw application. A good foundation was made about the ways of returning crop stalks. The details were as following:(1)The different effect of straw application on soil nutrient habitats,long–term and short-term straw application could improve soil organic matter, and the effect of short-term straw application was more obvious. The effect on the concentration of total N and available P in soil was not obvious in long-term straw application. Short-term straw application could enhance the concentration of available N and P in soil.(2)Long-term and short-term straw application could improve crop yield, while the effect of short-term was more obvious, the different content of NPK in grain cause by different soil habitats had an impact on crop yield. Long–term and short-term straw application could enhance crop yield by enhancing the content of soil available K. The concentration of NP in grain took on a linearity positive tendency along with crop yield in long-term localization experiment. Under short-term straw application, the content had a negative correlation with crop yield. Crop yield decreased first and then increased with the concentration of K in grain increased.(3)Under the condition of long–term and short-term straw application, the content of protein increased while the amylase content decreased while the content of soil total N increased. In long–term localization experiment, the chalkiness had a linearity positive tendency along with soil total N in long-term localization experiment, while it showed increased firstly and decreased subsequently under short-term straw application. The chalky rice rate increased, the protein content increased firstly and decreased subsequently while the amylase content was opposite with soil available K increased. Under the condition of short–term straw application, chalky rice rate and amylase content decreased, while the rate of head rice and protein increased, what improved processing and nutritional quality. Long-term and short-term straw application deduced the peak viscosity and breakdown of rice, increased setback, which caused low tasting quality.(4)Under the condition of long-term localization experiment, the Mg/K ratio of no-fertilization improved a little, long-term straw application could increase the Mg/K ratio in grain. The effect of short-term straw application was not steady. The two experiments showed that the amylase content increased with Mg/K ratio enhanced.(5)Synthesizing the above-mentioned conclusions, the sustainable time of straw application has different impact on soil nutrient, rice yield and quality. Generally, straw application could improve yield, enhance the rate of head rice and chalky rice rate, which could cause low tasting quality. In production, straw application should be coordinated with other cultivation approach in order to high quality of rice and high yield.