Study On Physiological Biochemical Characteristics And Fertilizer Recommendation Of High-yielding Maize

Grain problem is always related to the major strategic issues of China's national economic development and building a well-off society.The corn is the most important food, feed,the use of economic crops in China and the world.High and stable yield of maize bearing on China's food safety problems.Under the conditions in the high-yield fertilizer, maize yield formation is closely associated with leaves photosynthetic and membrane lipids peroxidation in the latter part of growth period.And so close to study these issues systematically,the mechanism of high-yield corn by nutrition can be further clarified. Scientific fertilization is an important part of high-yield corn.The effect on yield and various physiological and biochemical indicators by different quantities and ratio of nitrogen, phosphorus and potassium of material consumption and production is greatly.In this paper, the problems above are studied systematically,by the breed of Dongdan-60 and experiment design of "3414" in the field.The characteristics of photosynthesis and senescence,and production of spring corn are researched,test results and conclusions are as follows:(1)Within the scope of the trial design,with the amount of nitrogen fertilizer increased,the height,stere,diameter,leaf area and dry matter accumulation of maize increased and then decreased.Sufficient quantity for phosphorus,potassium is conducive to the plant height, stem diameter,leaf area and dry matter accumulation of corn.If phosphorus and potassium is dressed excessively,the growth of corn will be curbed.The significant level of the dry matter accumulation in grain of corn response to fertilization is:N＞K＞P;appropriate nitrogen, phosphorus and potassium content of corn can make filling early,maintain a relatively high rate of filling,and the extension of the filling stage of corn,forming the largest grain dry matter accumulation.Nitrogen,potassium overdose will stop filling the earlier,and lower grain dry matter accumulation.(2)After large trumpet period,the effect on LAI,LAD and NAR of fertilizer shows differences.LAI,LAD and NAR increased and then decreased as fertilization increased.The quantity of potassium reduces LAD,NAR late very significantly.The Chl a,Chl b in ear leaves both increase slow after the fast as the amount of nitrogen fertilizer increase. Phosphorus and potassium influence the chlorophyll content in ear leaves is mainly at later period,and they mainly affected Chl b.In milky stage Chl b raised the level at first and then reduce;Suitable phosphorus,potassium level performance an advantage of raising it.Pn, Cond,Ci,Tr in ear leaves all increased with application of nitrogen,phosphorus raising prophase.With the level of potassium increasing,Cond,Ci,Tr lowered;The impact of Pn by the potash fertilizer was not obvious.To sum up,appropriate amount of fertilizer can maintain a high photosynthetic capacity and extend the duration of leaves high photosynthesis.(3)Suitable nitrogen,phosphorus and potassium can increase leaves soluble protein and soluble sugar content in milky stage.The activity of SOD,POD,CAT in the ear leaves of maize,all increased at fiest and then reduced with nitrogen,phosphorus and potassium increase.MDA content increase first and then cut with fertilization raising in the milky stage. Nitrogen,phosphorus and potassium feasible application rate can increase maize leaves lipid peroxidation protection activity,too high or too low reduced activity of SOD,POD,CAT and premature aging earlier.(4)Through the analysis about the relationship among the amount of fertilizer,yield and yield components,we can see that different levels of nitrogen fertilizer impact on yield significantly,but phosphorus potassium fertilizer have not significant impact.Nitrogen major impact on grain weight and number of maize;potash fertilizer impact on bald pointed length significantly;the effect on yield component by phosphate fertilizer was not obvious.The high-yield fertilization for the test area is being raised:on the basis of a large number of organic fertilizer,N 210～220 kg·hm^-2,P₂O₅ 120～130 kg·hm^-2,K₂O 40～50 kg·hm^-2.(5)In every period,LAI and LAD is significantly associated with N application amount. Phosphorus,potassium related to reach or approach the significant level only at the first two periods,and correlation is not significant in the latest period.Correlation between NAR and fertilizer application amount,yield was not significant.Through analysis with the correlation of the physiological and biochemical indicators,we can see that Chl b,Pn,Tr and POD activity was significantly related to production;Cond,Tr,POD,CAT associated significantly to Pn;Chl a,Chl b and Chl a+b inter-related significantly;POD,CAT activity and Chl a,Chl b related more notable.