Study On The Effect Of Growth Traits And Nitrogen Efficiency Of Different Genotypes Of Rice On Different Nitrogen Fertilization

In order to explore the effect of growth traits and nitrogen use efficiency of 3 rice genotypes under different nitrogenous fertilization, the experiment was carried out in Lukou town of Changsha County in 2014. To studied the features of yield and yield components,growth traits and changes and distribution of dry matter and canopy spectral indices and photosynthetic rate and nitrogen accumulation and translocation and utilization efficiency of 3 rice genotypes's(Zhongjiazao 17?Zhuliangyou 819?Zhuliangyou 2008) in the four application levels of nitrogen (N0, N75, N150 and N225), The main results are as follows:1.The yield and yield components, plant height, spike rate and leaf area index among the 3 rice genotypes were significantly different. Zhuliangyou 819 obtained high yield at high nitrogen levels because of the high tiller number. During tillering stage and maturity stage, the number of tiller was higher than that of the other two varieties at different nitrogen levels. During tillering stage and mature stage, the tiller of Zhuliangyou 819 was more than others under different nitrogen levels. Plant height of shunxu is Zhuliangyou 2008> Zhuliangyou 819>Zhongjiazao 17. The contribution of yield components to yield is: Zhongjiazao 17:Effective panicle>1000 grain weight>grain number;Zhuliangyou 819 and Zhuliangyou 2008:Effective panicle>grain number>1000 grain weight. Increase the number of effective ears are the common way to achieve the goal of increasing the yield of 3 varieties.2.At heading stage, the total upper dry weight and nitrogen levels of Zhuliangyou 819 was significantly higher than others; In milk ripe stage, the total dry matter in the upper part of Zhuliangyou 819 and Zhuliangyou 2008 was significantly higher than Zhongjiazao 17; At mature period, the total dry matter in the upper part of Zhuliangyou 819 and Zhuliangyou 2008 was significantly higher than Zhongjiazao 17 in lower nitrogen application. Between the full heading stage and milk stage, growth rate of Zhuliangyou 2008 was the highest in nitrogen conditions; The growth rate of Zhuliangyou 819 is highest in the low nitrogen level between the milk ripening stage and mature period.3.At heading and filling stage of Zhuliangyou 2008, the SPAD value is the lowest, leaf color is shallow. The attenuation of chlorophyll content in leaves of Zhongjiazao 17 was slower than others two cultivars in nitrogen conditions in dough stage. Under the high nitrogen level, the total amount of nitrogen in the unit area of Zhuliangyou 819 and Zhuliangyou 2008 were higher than Zhongjiazao 17. At heading stage, the level of vegetation coverage levels of nitrogen was Zhuliangyou 2008> Zhuliangyou 819> Zhongjiazao 17. At milk ripening stage,,the total nitrogen content in the leaf of Zhuliangyou 2008 was the highest, and Zhongjiazao 17 was the lowest. At dough stage,the total nitrogen content in the leaf of Zhongjiazao 17 was the lowest in nitrogen condition.4.At heading stage and mature period, Nitrogen accumulation of Zhuliangyou 819 in different nitrogen levels were the highest. Nitrogen Agronomic efficiency of Zhongjiazao 17 is the least in nitrogen condition. Nitrogen Physiological efficiency of Zhuliangyou 2008 is the highest in nitrogen condition. Nitrogen dry matter production efficiency of Zhuliangyou 819 is the least in nitrogen condition. Partial factor productivity of applied nitrogen of Zhongjiazao 17 is the least in nitrogen condition.5.In nutrient efficiency classification, Zhuliangyou 2008 as not efficiency fertilizer tolerance type, the type under high nutrient conditions yield is low, and in low nutrient conditions yield is high, can adapt to low soil nutrient environment, and better yield performance; Zhuliangyou 819 is the high efficiency of fertilizer tolerance type, the type is in low nutrient and high nutrient conditions yield were higher, of soil nutrient supply wide adaptability, high soil fertility or low can have higher output, is the ideal goal of improvement of plant nutrition traits; Zhongjiazao 17 is low efficiency type, the type of low nitrogen and high nitrogen treatment yield is low, increasing the supply of nutrients to the type of rice varieties of a significant increase in yield is not obvious.