Effect Of Row Space On Population Index And Yield Of Maize

This research was carried out from 2014 to 2015 in two different ecological regions: Jinjia town, Changtu County, Tieling city, Liaoning province(Northern Liaoning); Daguben town, Fumeng County, Fuxin city, Liaoning province(Western Liaoning), using three different dense types of maize: DY39, ZD958 and LD588. And set five row spaces(50cm,55cm,60cm,65cm,70cm) to study the effect of row space on maize yield and canopy structure. This research can supply theoretical foundation for exploring the most suitable row space of maize for creating high yield group structure of spring maize in Liaoning province. The results were as follows:Different planting space led to different yield for different dense type of maize. Decreasing the planting row space appropriately was in favor of sparse planting variety hybrid-DY39 to obtain high yield, and the range of the row space was 50-60cm. Appropriately increasing the planting row space could improve the yield of close planting hybrid-ZD958 and LD588, and the range of the row space to abtain high yield was 60-70cm. 60cm equidistant row space planting could adapt different density tolerant hybrids in different ecological regions, obtain higher yield, and was suitable for popularization and application in Liaoning province.Planting spacing significantly affected the canopy structure of different maize varieties. Decreasing the planting row space appropriately was in favor of increasing the leaf area index of hybrid-DY39. Appropriately increasing the planting row was in favor of obtaining the most suitable leaf area index for close planting hybrid-ZD958 and LD588. The leaf orientation value of hybrid-DY39 was not significantly different in different row spaces. Leaf orientation value of ZD958 and LD588 was bigger under 50-55cm row space, but it didn’t decrease as the row space was greater than 60cm. The changes of canopy structural affected the corn field transmittance. Reasonable leaf area index could significantly reduce the light-leaking rate in the field, and reasonable leaf orientation value is helpful to optimize light distribution of canopy.Planting spacing significantly affected the photosynthetic characteristics of different maize varieties. Chlorophyll content of ear leaf of DY39 decreased with the increasing of row spaces. Chlorophyll content of ear leaf of ZD958 maximized under 60cm row space, and Chlorophyll content of LD588 maximized under 65cm and 70cm row space. The strength of the photosynthesis had a certain relationship with the chlorophyll content and light intensity. There are higher ear leaf chlorophyll content and more reasonable light distribution in the treatment with high photosynthesis rate of three types of maize.Planting spacing also affected the field microclimate of different maize varieties. The tendency of CO2 content varied with plant row spacing as same as the leaf orientation value. When the leaf area index was large, the CO2 content was higher. The field wind speed of the middle-lower canopy increased with the increasing of row space, however, it had a little difference between the treatments, because of the sparse leaves on the upper part of canopy. The temperature and humidity of field had a little difference between different row space treatments.