Effects Of Different Forms And Ratios Of Nitrogen On Nitrogen Utilization And Yield Of Maize Planting In Furrows Of Completely Mulched Alternating Narrow And Wide Ridges

Both supply of nitrogen and cultivation pattern are the important factors that affect the growth and yield formation of crop.Maize is one of the main crops in dryland of China,which has an important role in the sustainable development of social economy.Field experiment was conducted to study the effects of the different cultivation patterns,urea as control,the effect of nitrogen forms(1:0?1:1?1:3?3:1)on soil water content,soil temperature,dry matter accumulation,nitrogen uptake and translocation of maize.Influence of different forms of nitrogen fertilizer and cultivation pattern on yield and nitrogen utilization was studied.The result would provide theoretical foundation for efficient nitrogen use under the whole film double furrow sowing of spring maize.The main results are as follows:1.The treatment of full mulched alternating narrow and wide ridges with furrow planting could increase the soil temperature in early period of maize,compared with the whole film mulching planting.The soil average moisture content soil in 0-200 cm layer increased 2.62%.Nitrogen form ratio had no effect on soil temperature,but all the treatments of mixed supply of nitrate and ammonium fertilizer all could improve soil moisture.2.The treatment of full mulched alternating narrow and wide ridges with furrow planting had obvious advantages on increasing leaf area index and photosynthetic potential of maize.The leaf area index and photosynthetic potential were increased by 2.86%-27.27% and 7.86%-14.47,respectively,compared with the whole film mulching planting.Under the same cultivation pattern,the NO3--N and NH4+-N mixture ratio could increase leaf area index and photosynthetic potential of maize compared with the single nitrogen forms.When NO3--N and NH4+-N were used in combination,increased NH4+-N ratio was not conducive to the photosynthesis of maize.Increasing the proportion of NO3--N could improve photosynthetic performance.When the fertilizer ratio of NO3--N and NH4+-N was 3:1,the total photosynthetic potential of maize was higher 2.29%-15.17% than that of the other four ratios.3.Dry matter accumulation of the treatment of full mulched alternating narrow and wide ridges with furrow planting was increased by 6.53%-30.56% than that of the whole film mulching planting.It indicated that the treatment of full mulched alternating narrow and wide ridges with furrow planting was benefit to promote the dry matter transfer.Under the same cultivation pattern,the effect of nitrogen form ratio on the dry matter accumulation of maize varied with the nitrogen ratio.Single nitrate and urea significantly restrained the dry matter accumulation,and the treatment of mixed supply of NO3--N and NH4+-N could significantly promote the dry matter accumulation.The dry matter accumulation was the best,when the ratio of NO3--N and NH4+-N were 1:1 and 3:1.The dry matter transfer showed obvious advantages under the condition of a high proportion of nitrate nitrogen 3:1.The dry matter transport of vegetative organs increased by 7.36%-46.27%.Thecontribution rate of vegetative organs on dry matter was average increasing11.3% than that of the other four treatments.4.The whole film mulching planting significantly inhibited nitrogen accumulation,and reduced the contribution of nitrogen in the leaves and stems to grain,and average reduction of 8.20%,compared with the completely mulched alternating narrow and wide ridges with furrow planting.The nutrient uptake and nitrogen utilization of maize under the same cultivation pattern were the lowest under the treatment of applying nitrate fertilizer and urea alone.The treatment of mixed supply of NO3--N and NH4+-N could significantly promote the nutrient uptake of maize.The contribution rate of maize leaf and stem to grain nitrogen were improved with increasing of proportion of nitrate fertilizer.The treatment of1:1 and 3:1ratioof NO3--N and NH4+-N could increase nitrogen partial productivity.Among them,the ratio of 3:1 was the best treatment,which had the highest nitrogen uptake efficiency.The nitrogen uptake efficiency could increase average of 11.45% than that of the other four ratios.5.The yield and water use efficiency of maize were significantly affected by planting patterns and nitrogen forms.The treatment of full mulched alternating narrow and wide ridges with furrow planting could increase the ear length,ear diameter,ear row number and 100 grain weight of maize.The yield of it increased by 15.84% than the whole film mulching flat planting.Under the same cultivation pattern,the treatment of mixed supply of NO3--N and NH4+-N could significantly improve grain yield,it increased by 4.86%-29.57%,compared with CK.The treatments of NO3--N and NH4+-N mixture fertilizer significantly increased the water use efficiency of maize,compared with the single nitrate and urea.The water use efficiency of NO3--N and NH4+-N mixture ratios of different forms of nitrogen fertilizer had no significant effect.