A Study On Planting Density And Nitrogen Application Rates Of Maize Xianyu335 Based On Experiments Of Single-factor And Two-factor Interaction Effect

This study employs the maize variety of XianYu 335(XY335)as testmaterials. Based on single-factor and two-factor experiments andorthogonal tests, it explored optimum planting density and optimumnitrogen application rates on spring maize in moderate fertility soil of thecentral region of Jilin Province through systematic research from 2006 to2009. It aims to provide not only a theoretical basis for efficient maizecultivation, but also a better reference for guiding the region's agriculturalproduction and promoting food production. This study comes to thefollowing conclusions:1. Together with increasing planting density, plant height and earheight increased. Especially, when the density was above 80,000plants/hm~2 plant height increased obviously; stem diameter decreasedsignificantly; and bare plant rate and lodging percentage went higher thanother treatments significantly.2. Under different planting densities, chlorophyll content increasedfirst then decreased. The maximum of chlorophyll content appeared fromthe period from silking to grain filling stage. However, for differenttreatments of maize on the same period, it showed that chlorophyllcontent under lower density treatment was higher than that under higherdensity treatment. Both soluble sugar and soluble protein content showedtrends of first increased and then decreased,but the peak of soluble sugar appeared in filling stage,which soluble protein come out in jointingstage.3. With the amount of nitrogen application increased, plant heightincreased. Photosynthetic rate were significantly different betweendifferent N treatment and control. When the amount of nitrogen appliedwas less than 200kg/hm~2, increasing nitrogen application rate couldpromote leaf photosynthetic rate, and was helpful to photosynthesis.4. Maximal filling rate appeared on the first 16th day after filling. Butdifferent amount of nitrogen application has different effect on theduration. Maize under high-nitrogen treatment could maintain a higherfilling rate for a significantly longer time compared with that underlower- nitrogen treatment.5.Different density and N application affect maize yield significantlyin the three years test. Single-factor test regression analysis showed thatmaize planting density should be controlled between the 71,800-76,700plants/hm~2; the amount of nitrogen application should be controlledbetween 200 and 240kg/hm~2 in moderate fertility soil of the centralregion of Jilin Province. Further research through orthogonal testsshowed density and nitrogen application had significant effect on maizeyield and the highest yield appeared under the treatment of density is70,000 plants/ hm~2,240kg/hm~2 N application rates. Therefore, in order toachieve a higher production level, the recommended planting density is 70,000 plants/hm~2 and nitrogen application is240 kg/hm~2 for maizeproduction in this area.