The Study Of Source-sink Characters And Community Effects On High Yield Summer Maize

In this experiment, there are ZhengDan 958, DH3719, JingDan 28, JingKe 308, DanYu39, and NongDa108 used as materials, which have been studied that how their density has effect on the corn source, sink, as well as souce-sink ratio, and the ralationship between the souce-sink ratio and the yield. The purpose of this research is to find the corn characteristic of source and sink, finds the output limit factor, provides the theory basis for the high PrOduction cultivation. The main results are as follows:1. The density has influence on source: The higher the density is, the lower the area of leaf on a single plant ground is. Increases along with reduce, the community leaf area, LAI and the photosynthesis potential are increasing when the density is in an increase, the difference of the varieties is very significant. The daily increases of leaf area,LAI and the photosynthetic potential of the high-yield variety ZhengDan 958maintains at high level. They are slightly influenced by the density and decrease slowly in the later period of development, in which photosynthetic potential the drop scope is smaller than 18% in later period. Although leaf sources of the JingDan 28 is smaller than other varieties, the stay-green in 3000-5000/666.7m~2 is good and later period it is in a senescence gradually; Other varieties are very strongly influenced by the density and leaf displays a senescence quickly under the high density.2. The leaf energy and sugar content in leaf source increase along with the increase of density and readuce along with the development. The sugar content of ZhengDan 958 and JingDan 28 reached above 10kg/667m~2, 26.8～65.1% higher than that of other varieties, also maintain the high content in the later developments. The leaf energy is also obviously higher than other varieties in this time.3. The dry mass accumulates in single plant drop along with the density increase and the source material output rate increases along with the density increases. The leaf sources of Zheng Dan958 and stem sheath productivity are slightly influenced by the density In the varieties, of which the productivity is high. The transfer rate scope of leaf source is about 13～16% and the transfer rate scope of stem sheath is about 10%. The JingDan 28 is strongly influenced by the density. The productivity is middle and the later period declines slowly to maintain the high productive forces. The transfer rate scope of leaf source is close to Zheng Dan958. 4. The character in single plant reduces along with the density increase and the total number of seeds in the community sink increase along with the density increases. The kernel setting ability of high-yield variety ZhengDan958 in single plant is high, the community total number of seeds and the kernel weight are high, affected slightly by the density. The kernel setting ability of JingDan 28 in single plant is high, weight high, and the output is higher than other varieties.5. The sink capacity quantity increases along with the density increase and sink activity reduces obviously along with the density increase The high-yield variety ZhengDan958 in experimental density has high the storage capacity and simeactivities. The high-yield variety JingDan28 in its suitable density, 4000-5000 plant per mu(666.7m~2), the storage capacity achieves lagest; The grain is in the milk under 3000～5000 plant per mu(666.7m~2) densities is equally the 0.848g/100 grains·d, obviously higher than other varieties.6. The sink energy increases is not obvious along with the density changes and the difference between the density is obvious. The sink energy of the high yield variety ZhengDan 958 is higher than other varieties obviously, and it keeps high sink energy under any densities. NongDa 108 could keep high sink energy under high density.When the high-yield variety. JingDan 28 and DH3719 are under its suitable density 4000～5000 plant per mu(666.7m~2),the sink capacity achieves the maximum. The sink energy of DanYu 39 is lower. It is known that, when the sink energy is above 9.4×10~8 calorie, the grain output can achieve the high level Calorie.7. Discribing the source-sink ratio with the sink energy/leaf area ratio, the grain kernel weight/leaf area ratio, the sink/source energy, three kinds of source-sink ratio drop along with the density increasing. The source-sink ratio of the high-yield variety Zheng Dan 958 and JingDan28 are higher than others. The sink energy/leaf area ratio of these kinds of high-yield variety outdoes DH3719, the Dan Yu 39 and NongDa 108 15～27.5%. This research believed, the best state of equilibrium of source-sink ratio is the rate of grain and leaf between 0.16～0.2kg/m~2, the sink energy/leaf area ratio about 250kcal/m~2, the storehouse/source energy compared to between 3.0～4.0. The output of this time is the highest.