Effect Of Chemical Fertilizer With Humic Acid On Nutrient Absorption And Yield Of Maize

In order to reduce application proportion of fertilizers on the basis of ensuring the high and stable yield of maize,the optimal ratio of combinative application of humic acid and chemical fertilizer is discussed in this paper to provide theoretical basis for rational fertilization.By using the main maize variety "Xin Xin No.1" as the test material with adopting the method of field trial,a total of 6 treatments are set,including no fertilization(CK),routine fertilization(F5),reducing fertilizer application by 10%(F4H1),reducing fertilizer application by 20%(F3H2),reducing fertilizer application by 30 %(F2H3)and reducing fertilizer application by 40%(F1H4),in which the reducing fertilization treatments are full reduction of fertilization and adding different amounts of humic acid at the same time.The effects of different fertilizer operations on agronomic characters of maize,dry matter accumulation and distribution,nutrient absorption and accumulation,yield and its components and fertilizer utilization are studied.Here are the results.The height of maize plant increases constantly with the development of growth period,and the tendency of fresh weight of maize increases firstly and then decreases,both of which in F3H2 treatment are significantly higher than conventional fertilization treatment.However,the water content of seeds of reducing fertilization treatments decreases by3.60% ~ 20.20% compared with the conventional treatment.The dry matter accumulation of maize leaves and stalks increase and then decrease,while the grain increases steadily.As the growth period advances,the proportion of leaf and stalk of dry matter in the whole plant obviously decreases,and the grain proportion increases,which in F3H2 treatment are obviously higher than conventional fertilization treatment in mature period.The sequence of grain's dry matter accumulation at maturity is: F3H2>F4H1>F2H3>F5>F1H4,but there is no remarkable difference between F1H4 and F5.The sequence of entire plant's dry matter accumulation is: F3H2>F4H1>F5> F2H3>F1H4.While the nitrogen content of leaves and stalks and the nitrogen accumulation of bracts and corncobs decreases,the accumulation of nitrogen increases and then decreases;the nitrogen accumulation of grain(including at maturity)and maize increase.The nitrogen accumulation of entire plants in F3H2 treatment is the highest in mature stage,closely followed by F4H1 treatment.Meanwhile,the proportion of nitrogen content in whole plant increases,and the proportion of reducing fertilization treatments treated with humic acids is higher than that of conventional fertilization treatment.The total nitrogen accumulation of F3H2 treatment and F2H1 treatment are 7.21 % and 3.21 % higher than that of F5 treatment.While the potassium content of stalk decreases first and recovers slightly in mature stage,the phosphorus content of maize leaves and stalks decreases during the growth period,so does the potassium content of leaves.The accumulation of phosphorus and potassium in maize leaves and stalks increase firstly and then decrease.Both of the content and accumulation of phosphorus and potassium in bracts and corncobs trend down,while the phosphorus accumulation of grain increases.The sequence of the phosphorus accumulation of grain at maturity is: F3H2>F4H1>F2H3>F5>F1H4;on the contrary,the potassium accumulation of grain decreases,and here's the order of the phosphorus accumulation of grain at maturity: F3H2>F4H1>F2H3>F5>F1H4.The yield of 4 treatments reduced fertilization is higher than that of conventional fertilization treatment,with the range of increasing in yield by 0.82%~7.60%.There is no significant difference between F3H2,F4H1 and F2H3 treatment,however,all of which are different dramatically from F5 treatment.Reducing fertilizer application with humic acid replacement can improve the economic benefit of maize effectively,which makes net return be different markedly from the conventional fertilization treatment,exactly as the best synthesis effect of F3H2 treatment.The net yield of reducing fertilization application treatment increases by 9.48%~ 16.78% compared with the conventional fertilization treatment,as well as the utilization of nitrogen fertilizer increases by 9.48% ~51.19%,phosphorus fertilizer by 23.53%~51.28%and potassium fertilizer by 23.45%~ 49.94%.Comprehensive consideration of maize yield and nutrient uptake rules,with conventional fertilization reduction 20% ratio of humic acid as the optimal application rate.