Effects Of Fertilizer Treatments On The Key Physiological And Biochemical Indexes And Yield Traits In Spring Maize Zhongdan509

Maize is China's third largest food crops,but its yield is only about 50%of the developed countries,so China has great potential for maize production.In recent years,the effects of chemical fertilizers become gradually important in the agricultural production following the social development.Chemical fertilizer is regarded as“food in food”,and one of the important factors of maize growth and the yield.In this study,Zhongdan509,a spring maize,cultivar reccommded in Tianjin,was used to analyze the indexes of physiological and biochemical and yield under the different levels of N,P and K.This study will provide the theoretical and technical guidance for the high efficiency and high yield of Zhongdan509.The results showed as follows:1.The effects of different N fertilizers on the indexes of physiological and biochemical and yield in spring maize of Zhongdan509:As the N fertilizer increases,the yield rises at the start then falls.N application of137.01kg/hm~2 can achieve the highest yield and show significant differences from other N levels,so increasing a moderate amount of N fertilizer can increase the yield of Zhongdan509.With the increase of N fertilizers,the maize leaf soluble protein contents,SOD activities,POD activities,CAT activities,NRase activities,photosynthetic rates and chlorophyll content firstly rise and then falls.While the leaf soluble sugar contents fall at first and rise later on,and N application of 180.00kg/hm~2,can promote the highest leaf soluble sugar contents among three leaves stages.The leaf soluble protein contents at flowering stage,POD activities at big trumpet stage,photosynthetic rates and chlorophyll content reach the highest level as N application with 135.00kg/hm~2,.The activities of SOD and CAT activities at flowering stage and NRase at jointing stage achieve the highest level as N application with 180.00kg/hm~2.2.The effects of different P fertilizers on the indexes of physiological and biochemical and yield in spring maize of Zhongdan509:As the P fertilizers increase,the yield of Zhongdan509 rises at first and then falls.When P was applied with 78.53kg/hm~2,the yield reached the highest level,indicating that increases of P fertilizer application in a moderate amount can increase the yield of Zhongdan509.Following the P fertilizer increase,the maize leaf soluble protein contents,SOD activities,POD activities,CAT activities,NRase activities,photosynthetic rates and chlorophyll content rise in the beginning and falls thereafter,but the leaf soluble sugar contents changes conversely.The leaf soluble sugar contents is in the highest level under75.00kg/hm~2 of P.The leaf soluble protein contents and POD activities at big trumpet stage reach to the highest level as P application with 105.00kg/hm~2.SOD activities and CAT activities at flowering stage,NRase activities at jointing stage,photosynthetic rates and chlorophyll content are in the highest level with 75.00kg/hm~2 of P.3.The effects of different K fertilizers on the indexes of physiological and biochemical and yield in spring maize of Zhongdan509:With the K fertilizer increase,the yield rises at first and falls later on.Zhongdan509obtains the highest yield under K application with 70.50kg/hm~2,so increase with a moderate amount of K fertilizers can increase the yield of zhongdan509.Following the K fertilizer increase,the maize leaf soluble protein contents,SOD activities,POD activities,CAT activities,NRase activities,photosynthetic rates and chlorophyll content firstly rise and then falls,but the leaf soluble sugar contents show the converse trend.The leaf soluble sugar contents are in the highest levels at all three leaves stage as K application with 67.50kg/hm~2.The leaf soluble protein contents at big trumpet stage,NRase activities at jointing stage,SOD activities and POD activities at flowering stage,photosynthetic rates and chlorophyll content reach the highest levels with 67.50kg/hm~2 of K.CATI shows the highest level at flowering stage as K application with 90.00kg/hm~2.4.Under the quadratic regression orthogonal rotary design,N cooperation with P and K can outline the optimum fertilization scheme of Zhongdan509.The highest yield,10363.13kg/hm~2,can be achieved at 114.65kg/hm~2 of N,73.03kg/hm~2 of P and 60.95kg/hm~2of K.