Effects Of Different Planting Density On Maize Population Structure

At present,there are two main ways to promote further improvement of maize yield per acre,creating new breeds suitable for large-density planting.The other and most important is to increase plant density,but when the plant density is too large.At that time,when the number of plants per unit area was excessive,the competition for nutrient absorption by plants became more intense and fierce,eventually resulting in a decline in the harvested grain output in the actual mature period in the community.In this experiment,the model plant “Zhengdan 958” and the new dense-tolerant variety “Shaandan 636” were selected.These two types of corn varieties differed in the density of planting responses.They were set in two ecological zones in Yangling and Changwu.Intensive plant density,the extent of research on the extent of intensive conditions for different densities of adaptive summer maize seed pods individual output and the actual output of the district.The main results are as follows:1.In the two ecological zones,with the gradual increase of plant density,the ear heights of Shandan 636 and Zhengdan 958 are elevated and the plant heights are gradually reduced but the differences are not significant.The strains of Zhengdan 958 under the conditions of plant density The height is higher than Shandan 636.2.The individual leaf area gradually decreased with the increase of plant density,and the leaf area index(LAI)gradually increased with the increase of plant density.However,the LAI of both varieties was higher in Yangling than in Changwu.In Yangling and Changwu Ecological Zones,the SPAD value of Shandan 636 was higher than that of Zhengdan 958 at the same density.3.The individual dry matter storage capacity was gradually reduced as the plant density increased,and the total dry matter in the plot gradually increased with the increase in the plant density.In the Yangling Ecological Zone,683 individuals in the dry matter and plots The total dry matter was lower than that of Zhengdan 958.With the development of growth,the dry matter content of Shandan 636 and Zhengdan 958 was gradually reduced in addition to grain,while the translocation rate in grains was gradually increased.Both the panicle length and the panicle diameter were gradually reduced as the plant density increased,and the long-lasting lengths of both varieties were reduced.As the plant density increased,the number of bank lines of Shandan 636 in Yangling Ecological Zone first increased.The dynamic trend of reduction,the number of clever lines in Zhengdan 958 is a dynamic trend of gradual reduction.In Changwu Ecological Zone,the number of clans in Shandan 636 shows a tendency of gradual reduction.The actual output of the communities in Shandan 636 and Zhengdan 958 were gradually reduced as the plant density increased.4.Through the regression analysis of the actual output of the Shandan 636 and Zhengdan 958 communities in different ecological areas,it can be seen that in the Yangling Ecological District,when the Shannong 636 individual plant productivity was 72%,the actual The highest output was achieved.When the single plant productivity of Zhengdan 958 was 67%,the actual output of the community was the highest.In the Changwu Ecological District,when Shandan 636 had an individual productivity of 56%,the actual output of the community was the highest.When the single plant productivity of Zhengdan 958 was 64%,the actual output of the community was the highest.