Effects Of Nitrogen Application Rate On Yield And Quality Of Different Quality Seedlings Of Kenjing No. 5

This test was conducted in Heilongjiang Bayi Agricultural University. Kenjing5was used asexperimental material, to study the effects of nitrogen fertilizer on rice seedling quality and theyield and quality of rice after different quality seedlings transplanting. Completely randomizedexperimental design was adopted. The results are shown as follows:1. The seedling height, leaf age reached the maximum when nitrogen application amountunder the condition of36g/m2, differences between the treatments and control reachedsignificant level. Root length reached the maximum when nitrogen application amount under thecondition of12g/m2, root number, terrestrial dry matter, root growth ability are all reached themaximum when nitrogen application amount under the condition of24g/m2, differences betweenthe treatments and control reached significant level.Base stem width also reached the maximum,but the difference was not significant.2. Whether applying nitrogen fertilizer or not, strong seedling LAI was higher than that ofweak seedling at tillering stage and full heading stage, the differences reached significant levelwhen nitrogen application amount under the condition of300kg/hm2. The dry weight of strongseedling was higher than weak seedling of each treatment at tillering stage, full heading stageand ripening period. The differences reached significant level when nitrogen application amountunder the condition of300kg/hm2at tillering stage.3. With the increase of nitrogen amount, spike length, primary branch number, secondarybranch number and filled grain number were all increased. When nitrogen application amountunder the condition of300kg/hm2, middle primary branch number of strong seedling wassignificantly higher than that of weak seedling, the lower part primary branch number of strongseedling was significantly lower than that of weak seedling. Whether applying nitrogen fertilizeror not, the filled grain number in different parts of strong seedling was higher than that in weakseedling.4.Without nitrogen fertilization, spike number per unit area, grain number per spike, seedsetting rate,1000-grain weight and yield of strong seedling were higher than those of weakseedling. In addition to the seed setting rate，the rest of the indicators of weak seedling increasedgradually with the increase of nitrogen content. Except spike number, each index of strongseedling showed an upward trend.When nitrogen application amount under the condition of225～300kg/hm2, the differences of yield reached extremely significant level.5. The agronomic efficiency of strong seedling were higher than that of weak seedling underdifferent nitrogen levels except150kg/hm2, with the increase of nitrogen, the partial factor productivity of two kinds of seedings were decreased, the strong seedling were higher than weakseedling under different nitrogen levels.6. Without nitrogen fertilization, percentage of brown rice, percentage of milled rice andpercentage of head rice of strong seedling were higher than those of weak seedling.Chalky ricerate and chalkiness degree of strong seedling were significantly lower than those of weakseedling; rice eating quality of strong seedling was higher than that in weak seedling. With theincrease of nitrogen amount, the rice eating quality indicators of strong seedling were decreased,when nitrogen application amount under the condition of225kg/hm2, rice eating quality waslower than that of the control.7. Whether applying nitrogen fertilizer or not, head rice yield of strong seedling was higherthan that in weak seedling. With the increase of nitrogen amount, the gap between them firstdecreased and then increased, under the condition of high nitrogen fertilization,（225～300kg/hm2）, head rice yield of strong seedling was significantly higher than that in weakseedling.