Font Size: a A A

Effects Of Plastic Film Mulching And Nitrogen Application Rate On Yield And Utilization Of Soil Water And Nitrogen Of Dryland Spring Maize

Posted on:2019-05-28Degree:MasterType:Thesis
Country:ChinaCandidate:Z L WangFull Text:PDF
GTID:2333330569977686Subject:Plant Nutrition
Abstract/Summary:PDF Full Text Request
Spring maize is one of the important crops in dryland farming areas of the Loess Plateau.Water is the most important factor limiting the yield of dryland crops in the region.Plastic film mulching is an important measure to improve the yield of dryland farming on the Loess Plateau.This study aimed to investigate the effects of plastic film mulching and nitrogen application on dry matter accumulation,nitrogen uptake and distribution,and yield of spring maize during dryland farming,as well as on soil mineral nitrogen and efficiency.The impact of water use will further explore the support and regulation of root nutrient moisture for high-yield groups,and provide theoretical basis for water-saving and high-yield spring maize and efficient use of fertilizers in dryland.The main results are as follows:?1?The effects of nitrogen application rates and plastic film mulching on the grain yield of spring maize show that nitrogen application rates,plastic film mulching and interaction of two factors significantly increased grain yield and yield components of spring maize,and nitrogen application rates under plastic film increased the grain yield and yield components of spring maize.Under the condition of plastic film mulching,the grain yield and yield components of nitrogen application rate of 250 kg/ha were the best,and the highest nitrogen harvest index was above 70.0%.However,excessive nitrogen application was not conducived to the improvement of grain yield and its components of spring maize.?2?Effects of nitrogen application rates and plastic film mulching on the dry matter accumulation of spring maize revealed that nitrogen application rates,plastic film mulching,and interactions between two factors significantly increased leaf area index,dry matter accumulation at each growth stage and post-silking dry matter accumulation and proportion of spring maize.The highest of leaf area index,dry matter accumulation,and post-silking dry matter accumulation and proportion were all attained by nitrogen application rate was 250kg/hm2 under plastic film mulching.Excessive nitrogen application rates was not conducive to the accumulation of dry matter accumulation at each growth stage and proportion of dry matter after anthesis.?3?Nitrogen application rates and plastic film mulching and interaction between two factors significantly increased nitrogen accumulation and post-silking nitrogen accumulation at all growth stages of spring maize.Nitrogen accumulation and post-anthesis mulching were all attained by nitrogen application rate was 250 kg/hm2 under plastic film mulching.Excessive nitrogen application rate was not beneficial to increase nitrogen accumulation and post-silking accumulation.?4?Nitrogen application,plastic film mulching,and interactions between two factors significantly increased nitrogen content of different organs and nitrogen transfer amount of vegetative organs.Under the condition of plastic film mulching,the nitrogen transfer amount of stems and leaves of nitrogen application rate 250 kg/hm2 was the highest,which was30.7-31.6 kg/hm2 and 65.6-66.6 kg/hm2,respectively,which was not significantly different from that of the nitrogen application rate 400 kg/hm2.?5?Nitrogen application increased the accumulation of ammonium nitrate nitrogen at0-100 cm,100-200 cm,and 0-200 cm soil layer after harvest.The plastic film mulching reduced the content of ammonium nitrate in the soil under the same nitrogen application rate,and reduced the accumulation of ammonium nitrate nitrogen at 0-100 cm,100-200 cm,and0-200 cm soil layer after harvest.?6?Plastic film mulching did not significantly increase the water consumption during the whole growth period of spring maize,but changed the stage water consumption of spring maize.Plastic film mulching significantly increased water use efficiency under the same nitrogen application rate.For N250 treatment,the water use efficiency of plastic film mulching treatment was 40.6 kg ha-1 mm-1?2016?and 30.5 kg ha-1 mm-1,respectively.?2017?,the water use efficiency of no mulching treatment were 29.1 kg ha-1 mm-1?2016?and 12.9 kg ha-1 mm-1?2017?.
Keywords/Search Tags:Dryland maize, Plastic film mulching, Dry matter accumulation, Nitrogen transfer, Nutrient and moisture of root layer
PDF Full Text Request
Related items