Studies On The Nutritional Physiology And Qualitative Character Of Film Mulched Rice

The biological, nutritional physiology and qualitative character of film mulched rice were studied in this paper. The results were as follows:The film mulched rice grown better, tilled faster than the conventional flooded rice. But its growing period was a little bit delayed in less rainfall year. In normal, all of the plant height, biomass, flag leaf area, chlorophyll content and root-shoot ratio of film mulched rice increased, which is significant at later growth stage Increasing of yield for film mulched rice was mainly due to increasing of its available panicle number, and the percentage of ear bearing tiller was some decreased. Compared to ripened grain and 1000-grain weight, the spikelet number per panicle of film mulched rice was easily affected by environmental condition.The poor environmental conditions such as high air temperature and soil drought negatively affected on the growth of film mulched rice. In this cases, NOs'-N content in the rice plant was obviously declined and NH/-N content largely increased, MDA and proline ( Pro ) content in leaves also increased. Moreover, nitrate reductase( NR) activity, glutamine synthase( GS ) activity, root oxidation and reduction activities of film mulched rice were strongly prohibited.In general, film mulching cultivation was helpful to increasing NOa'-N and NH4+-N content of rice, especially NOs'-N. At heading, NOa'-N concentration in the roots, basal stems and leaves of film mulched rice was as much 3.8 times, 7.9 times, 5.4 times as flooded rice. However, the cultivation had little effect on MDA, Pro and soluble sugar content. The NR activity, root oxidation and reduction activities of film mulched rice were usually higher than flooded rice, especially around jointing stage. GS activity had a little increase in film mulched rice.Film mulched cultivation could enhance uptakes and accumulation of nitrogen(N),^phosphorous(P) and potassium(K) in rice plant and grain, especially at middle and late growth stage. N and K content in film mulched rice plant increased much more than paddy rice, and P content was a little more in each growth stage. Film mulched rice had a nitrogen use efficiency (NUE) of 38.28%, increasing by 12.27%, compared to 26.01% for conventional paddy rice. Furthermore, N, P and K uptakes of rice were remarkably positive correlation with its yields, which was one of the mechanisms of promoting yield of film mulched rice.Some improvement happened to film mulched rice quality, whose milling quality (brown rice, milled rice and head rice ) had a little promotion, whose appearance quality had some increase with its chalkiness evidently decreasing compared to paddy rice but translucency less changing, whose cooking and eating quality showed that alkali spreading value was increased, gelatinization temperature was decreased, amylose content had some a little promotion, gel consistency became short, whose nutritional quality showed that protein content and amino content all had some extent elevation. It was showed that film mulching cultivation >uncovering cultivation> flooding cultivation for protein content, total amino acid content, total content of 16 amino acid measured, total content of 8 necessary amino acid measured in film mulched rice grain. As it is, phenylalanine ( Phe ) , arginie( Arg ), aspartic acid (Asp) and leucine ( Leu ) in film mulched rice grain increased by 7.4%~25.9%, 8.0%~ 24.1%, 1.1%~22.0% and 6.5%~30.4%, compared to paddy rice. Lysine ( Lys ) content in film mulched rice grain was some increase, too. On the whole, film mulched rice quality had some promotion.