The Effect Of Different Fertilization Systems To Yield And Quality Formation Of Summer Maize And Its Physiological Mechanism

The experiment was carried out in year of 2003 relying on long-term fertilizer experiments, which initiated in 1990, in fluvo-aquic soil in Changping County, Beijing, China, to explore the physiological and biochemical mechanism of yield and quality formation of summer maize under Different Long-term Fertilization Systems. The main results are as follows: 1. Soil fertility of different fertilization systems Organic matter(OM) and mass elements of CK were all lower than other fertilization treatments. S content of CK was more higher, Ca, Mg and Fe content were in middle level, Mn, Cu and Zn was more lower, pH of it was higher than all the other treatments. OM and all mass elements content of fertilization treatments were higher than CK: Soil of balanced fertilization of N, P, K(NPK treatment) had a middle level of soil fertility. Unbalanced fertilization treatments of NP, N and CK have the lowest rapid-efficiency kalium compared with others, treatments of N, NK and CK have the lowest total phosphorus and available phosphorate of soil, total nitrogen and alkaline nitrogen of NP, N, NK and PK were lower relatively. Combined application N, P, K chemical fertilizers with manure or crop straw (NPK+M, and NPK+S) had higher contents of OM, total N & P, available N, P & K than other treatments, mid-microelement contents of them were higher than middle level. 2. Yield and quality of maize in of different fertilization systems (1) Growth rate of NPKM, NPKS, NPK, NP and PK were closed, growth rate of the three imbalanced treatments: N, NK and CK, delayed 2 to 3 weeks than others, and there were significant difference in plant height, yield of dry matter, properties of ear (ear length, bald length, grain numbers per ear, grain weight per 1000 kernel), it is to say that the source capacity and sink size of N, NK and CK were lower obviously compared with other treatments. Yield of all treatments was in the descending sequence: NPKM>NPKS>NPK>NP>PK>NK>CK>N. (2) Protein, free amino acid and lysine contents and yields of stem and leaf in balanced fertilization(NPKM, NPKS, NPK) and NP treatments were higher than others', especially than N and NK treatments, change reverse in seed. There was difference of nutrient in different harvest organs of treatments. Protein and Lys contents and yields of harvests in NPK, NPKM and NPKS treatments were higher than imbalanced treatments remarkably. There was difference of nutrient in different harvest organs of treatments. 3. Physiological and biochemical mechanism of yield and quality formation of maiz in different fertilization systems (1) Analyzed from the averaged results of different harvest organs: total nitrogen content of NK was the highest, N treatment after it, PK was the lowest. Percent content of inorganic phosphorus: PK was the highest, NPKM was lower than NP', CK was the lowest. Potassium content of NK was the highest, NPKM after it, NP treatment was the lowest. Concentration of mid-microelement of different harvest organs, analyzed about the averaged results, NPKM treatment had the highest Ca concentration and the lowest Mg, S and Zn concentration. Fe concentration of NPKS treatment was the highest. Mn concentration of NPK was higher than others'. NP treatment had the highest Mg concentration. S concentration of N was the highest. NK treatment had the highest Zn concentration and the lowest Ca and Fe concentration. Mg, Mn and Cu concentration of PK treatment were all the lowest. CK had the highest Cu concentration (2) During growth duration, soluble sugar content of stem of NPKM, NPKS, NPK and NP were all lower than imbalanced fertilization treatments N, NK, PK and CK, but the averaged result of leaf of N, NK and CK were lower than others'. Soluble sugar content of seed, averaged the growth duration result, PK was the highest, NPKM after it, NK was the lowest. there was obvious difference between soluble sugar content of different harvest organs,the average results of different harvest organs, N, NK and CK content was higher than others, there wasn't evident discrepancy between NPKM, NPKS, NPK, NP and PK treatments. (3) Soluble protein percent content of ear leaf and seed in PK treatment was lower than others'highly during all the growth duration. Averaged the result of the growth duration, NK, NP and N content were higher than NPKM, NPKS and NPK. Soluble protein percent content of seed had the contrary result compared with ear leaf. (4) Morpha development of NPKM, NPKS, NPK, NP and PK treatments'plant were identical basically, but there were distinct difference of these treatments'LAI: the leaf of PK treatment senescence rapidly, and PK LAI was all more smaller during growth duration. LAI of NP was smaller than balanced fertilization treatments. There wasn't obvious between LAI of balanced fertilization treatments, and NPKM's was the biggest during growth duration. Morpha development of N, NK and CK Plant delayed badly, LAI of these treatments were lower than others'by a long way, and there wasn't a high point of LAI lasting out during the growth duration. Chlorophyll a(Chla) content of imbalanced fertilization treatments were lower than the balanced fertilization treatments', especially PK treatment. Chla content of N, NK and CK was smaller higher than PK. There wasn't obvious difference between Chla contents of balanced fertilization treatments and NP treatment. Chlorophyll b(Chlb) and Chlorophyll(Chla+b) contents of treatments had the same changing trend as Chla. (5) The sucrose content of ear leaf, averaged 28 days after silking, in different treatments were in the descending sequence: NK>N>CK>NP>PK>NPK>NPKM>NPKS. The sucrose content of seed in PK treatment was higher markedly than others', N treatment was lower only than PK. The content of CK was the lowest. There wasn't obvious difference with other treatments. Sucrose content of imbalanced fertilization treatments was higher than balanced. (6) Enzymes'activity of carbon metabolism: SS activities of ear leaf in balanced fertilization treatments and NP treatment, averaged 28 days after silking, were higher obviously than N, NK, PK and CK, NP was the highest and PK lowest. SS activities of seed: balanced tratements were higher than imbalanced 21 days after pollination. When talked about the SPS activity: SPS activity of leaves, averaged 28 days after silking, NPKS and NPKM were in the next place. N treatment perennially had the lowest activity. SPS activitiesof seeds in different treatments had the same trend as SS activity of seeds: PK treatment was the highest, NPKS, NPKM and NPK were next and CK lowest. ADPGPPase activities of ear leaf in imbalanced fertilization treatments were higher than balanced. But seeds had the adverse results: NPKM activity was the highest, N and CK had the lowest activity. UDPGPPase activities of ear leaf and seed in different treatment had the same change basically as ADPGPPase. SSS and GBSS activities of seed in different treatments had same trend by and large: balanced treatments were higher than imbalanced. SSS and GBSS activities of NPKM treatment were all higher than others', NP, N, NK and CK were the lowest. PEPcase activity of NK treatment was the highest, N and CK were in the second place, and NPKM was the lowest. (7) Enzymes'activity of nitrogen metabolism: NRase activities of leaf in balanced fertilization treatments were higher than imbalanced, NPKM was the highest, imbalanced treatment of NP activity was higher than other imbalanced. PK was lower than others'markedly. GS activity per fresh weight of leaves in N, CK, NK and PK were higher than other treatments', NP was the lowest. GS activity of seeds, averaged 14~28 days after silking, N treatment was the highest, and CK lowest. GOGAT of leaves in N treatment were higher than the other treatments. GOGAT of leave in PK treatment was the lowest. GOGAT activity in seed of NPKM was the highest, PK and CK were more lower than others'. GDH of leaves in N, NK and CK treatment were higher than others', NPKM was the lowest. GDH of seeds were reverse compared leaves, NK was the highest, and CK lowest. (8) Metabolism of active oxygen: SOD activities of leaf and seed in NP treatments were all higher than others', SOD activities of leaf of NPKM and NPKS treatments were next to it, and PK was the lowest. POD activity of NP's leaf was the highest, and PK was the lowest, NPKM was higher only than PK. POD activity of seed in NPKM treatment was the highest, and CK, NK and N were lower. CAT activity of leaves was the same as POD activity of leaves. CAT activity of seeds, mean of 14 to 28 days after silking, is in the descending sequence: NPKS>NPKM>NP>NPK>PK>CK>NK>N. MDA content of leaves and seeds in NPK, NPKM, NPKS and NP treatments were all higher than others'. MDA content of PK's leaf was the lowest. MDA content of seed in PK treatment was higher than NK, and lower than others'.