Effects Of Nitrogen Rates On Grain Yield,Quality And Functional Characteristics Of Functional Rice

Functional rice is a kind of Rice variety which contained one of Several nutritive element that can ameliorate physiologic function of Human Body after edible, as the China’s economy develop rapidly, People began to live a well-off life, The requirements of rice were more and more high. To meet the requirements of rice nutrition and health care, the research of functional rice becomes hotspot. Field experiment involving six functional rice cultivars with low glutelin rice, giant embryo rice, iron-rich rice, Resistance-storage rice and five nitrogen(N) fertilizer treatments was performed at Danyang city of Jiangsu province experimental station in2010and2011to determine the effects of nitrogen rates on grain yield and its components, processing quality, appearance quality, nutritional Quality, functional properties of functional rice. The main results were shown as follows:(1)Grain yield and its components:With increased N level, the grain yield of six functional rice increased first and then decreased, the differences between nitrogen fertilizer treatments reach significant level. Grain yield reach the highest when the N level was270kgl r-2. The nitrogen application mainly affected the panicles and spikelet per panicle, however Seed-setting percentage and1000-grain weight were less effected by N level. The responds of grain yield to N level was different during the six functional rice, for example low glutelin rice W1721, W3660, giant embryo rice W025and Resistance-storage rice WO17showed relatively more stable under five N treatments compared to iron-rich rice H9405and low glutelin rice W1240. As N level increased, LAI of heading stage, the N-requirement per100kg grain, the dry matter of mature stage and Total amount of N-absorption increased significantly, however nitrogen harvest index(NHI) and nitrogen use efficiency(NUE) show decreasing trend.(2) Milling quality and appearance quality:With increased N level, brown rice rate and milled rice rate head rice rate increase, significant genotype difference was found among six functional rice, brown rice rate and milled rice rate head rice rate were highest for low glutelin rice W1240and lowest for iron-rich rice H9405. As the N level increased, grain length, grain with and chalky ratio decreased, however length-width ratio slightly increased. The nitrogen application mainly affected the chalky ratio, the grain shape was less effected. Chalky ratio of different functional rice had different sensitively to N level, such as low glutelin rice W1721, iron-rich rice H9405exhibited relatively more stable under contrasting N treatments compared to low glutelin rice W1240, W3660and Resistance-storage rice W017.(3)Nutritional Quality:With increased N level, Amylose content decreased, the increase amplitude was biggest for low glutelin rice W1721and giant embryo rice W025but smallest for iron-rich rice H9405. The protein content in brown and milled rice increased significantly with increasing the amount of nitrogen applied; the increase amplitude in the brown rice was biggest for W3660and Resistance-storage rice W017but smallest for low glutelin rice W1240and giant embryo rice W025, however was biggest for iron-rich rice H9405and Resistance-storage rice W017but smallest for low glutelin rice W1240and giant embryo rice W025in the milled rice.(4)The Protein components of function rice:Compare to the conventional rice, LGC rice had the higher gliadin content but smaller glutenin Content both in the brown and milled rice. With increased N level, four protein protein components increased significantly, The nitrogen application mainly affected gliadin and glutenin contents, albumin and globulin less effected. Gliadin and glutenin in the brown rice, glutenin content in the milled of LGC rice were less effected by nitrogen fertilizer than conventional rice. The extent of glutenin content and its respond to nitrogen fertilizer in the there functional rice were showed as follow:W1240<W1721<W3660. We can know from Nitrogen fertilizer efficiency equation of the grain yield and glutenin content that the highest nitrogen rate of LCG rice W1240, W1721, W3660were about342kg/hm2.265kg/hm2和47kg/hm2respectively In this experimental conditions.(5)Fe absorption and distribution:Fe content of the whole plant, peduncle, hull, rice bran, milled rice and its distribution in the grain of iron-rich rice H9405at mature stage were significantly higher than that of W1240. With the increase of N fertilizer application, two varieties’Fe content and total Fe uptake amount of the whole plant significantly increased at heading stage and mature stage; Effects of N fertilizer on the Fe distribution in different part of rice in iron-rich rice H9405had the same trend with W1240at heading stage. However, with the increase of N fertilizer Fe distribution of grain at mature declined in iron-rich rice H9405, while increased first and then decreased in W1240. Higher N fertilizer could increase the Fe content in the milled rice, the difference was significant in the iron-rich cultivar H9405at N application rate of270kg-hm"2, especially.