Effect Of NPK Fertilization On Dry Matter Production, Nutrient Uptake And Soil Enzyme Activity Of Winter Wheat In Lime Concretion Black Soil

For clear the limiting factors of winter wheat production in lime concretionblack soil,making a high-efficient and high-yield Fertilization technology model for thecultivation of winter wheat. Under the field condition, taking nitrogen, phosphorus andpotassium three elements as different processing for tests methods, set up six treatments:without any fertilizer (CK), nitrogen (N), nitrogen and phosphorus (NP), nitrogen andpotassium(NK), phosphorus and potassium(PK) and balanced NPK as1-0.5-0.4(NPK), effectsof different NPK on dry matter production, grain yield, plant nutrient uptake and soil enzymeactivity of winter wheat were studied at Shangshui county in Henan Province during2012to2013. The main results were as follow:1. The number of wheat tillers and ears is greatly influenced by nitrogen nutrients, and thedynamic trend of each treatment is consistent, the number first increased and then decreasedwith the growth process, and it reached the peak at jointing stage. After wintering period, thenumber of wheat tillers of each Nitrogen treatment was significantly higher than the number ofNo nitrogen treatment. Wheat dry matter accumulation presents "S"-type change with theadvancing of reproductive process. Dry matter production rate is low in wintering stage to thejointing stage., and the dry matter accumulated very rapidly after jointing. The dry matteraccumulation of each nitrogen treatment was significantly higher than No nitrogen treatment.NPK fertilizer cooperating application significantly increased transfer rate of stem and leaf drymatter, and increase the contribution rate of vegetative organs dry matter to grain beforeflowering. It laid the nutrition foundation for the high yield of wheat. In wheat production inlime concretion black soil area, nitrogen significantly reduced sterile spike per panicle andreduced the number of lower-level flower missing. It significantly improved the three elementsof the yield and harvest index. Although thousand kernel weight of No nitrogen treatments wassignificantly greater than the nitrogen treatment, but the yield components is uncoordinated.Reasonably balanced fertilization has a significant role in reducing the number of sterile spikeper panicle, improving seed kernels per ear, and increasing production.2. Under the conditions of N、P、K fertilizer, the main source of grain N、P、K elementswas the organs accumulation N、P、K pre-anthesis. In all treatments, the treatments NPK, N andNP are more conducive to the accumulation of nitrogen and phosphorus in pre-anthesis, the treatment NPK was significant on promoting the accumulation of potassium in pre-anthesis.The nitrogen use efficiency of no nitrogen treatments were significantly higher than that ofnitrogen, and the nitrogen harvest index of nitrogen treatments were significantly higher thanthat of no nitrogen treatments, the nitrogen uptake efficiency and nitrogen fertilizer productionefficiency were not significant in different treatments between the two. Compared with PK, thephosphorus uptake efficiency and phosphate fertilizer production efficiency of NP、NPKreached extremely significant. Compared with other treatments, the phosphorus use efficiencyof NK、NPK was significant, the phosphorus harvest index can be significantly improved bynitrogen. Compared with PK, the potassium uptake efficiency and potassium productionefficiency of NK、NPK was significant. The potassium use efficiency shows NP> NK> N>NPK> CK> PK. Compared with CK, N, NP, NK, PK, the potassium harvest index of NPKtreatment was significant, as the smallest.3.Under the experimental conditions, effects of different fertilization treatments on soilenzyme activities is different. On the whole, the biggest treatments of urease activity is PK orCK. Sucrase activities most were not significant in0-20cm. Soil sucrase activities wassignificant between each treatments in the stages addition to anthesis in the20-40cm. Mostly,the biggest treatments of phosphatase activity is N, NP, NK and the smallest is NPK, PK, andthey are significant most of the time. From the different growth stages of wheat, soil ureaseactivity is consistent in every soil layer, all is the anthesis stage> before sowing> jointingstage> maturity stage. The largest stage of each treatment soil sucrase activities is the maturestage, the second is the jointing stage and the minimum is before sowing, in addition to thetreatment NP which the maximize before sowing, the second is the jointing stage, the smallestis anthesis in0-20cm. But it is different in20-40cm soil layer, the largest stage of eachtreatment soil sucrase activity is the jointing stage, the lowest is before sowing in addition toCK and NP treatments are anthesis in20-40cm soil layer. The lowest stage of every treatmentphosphatase activity is before sowing, the highest stage is anthesis stage in addition to the NPtreatment which is jointing stage. From the vertical distribution of soil, the enzyme activities in0-20cm were greater than20-40cm its enzyme activity mostly in the important growth stage ofwinter wheat, so soil enzyme activity has a very good vertical distribution.4. The main nutrient limiting factor is nitrogen in lime concretion black soil area, nitrogencan improve the tillers, the absorption and accumulation of nitrogen, phosphorus, potassiumand grain numbers per spike of wheat significantly, and then increase the grain yield. It isimportant that balanced NPK fertilization on fertilizer use efficiency of wheat and guaranteethe absorption of nutrients in wheat growth stages. And if lack any one of the N, P, K, that will lead to the corresponding nutrient deficiency or excess apparently, and then affect the wheatyield. So, the important agronomic measure to improve wheat yield quality is nitrogen,phosphorus and potassium element reasonable ratio in lime concretion black soil area...