Abstract:

【Objective】 In order to increase the yield of maize, the effects of planting density on the yield and development of mazie ear were studied. 【Method】 Statistics of floret quantity and silking progress were made in field experiment, and normal paraffin sections were used to observe the development and structure of maize ear. 【Result】 The differentiation of florets of maize ear was postponed with the increase of the planting density. The silking number decreased at primary and middle silking stage, but was not significant at late stage with the increase of the planting density. The number of total florets, silking florets, fertilization florets and plumpness decreased, but the number of nonfertilization florets and the degenerative rate increased with the increase of the planting density. The total number and area of vascular bundles and phloem area of maize ear-axis decreased with the increase of the planting density. The yield was the highest at the planting density of 75 000 plants/hm2. The data analysis indicated that the total number and area of vascular bundles and the phloem area of maize ear-axis had a remarkably negative correlation with the planting density, but had a positive correlation with the kernel weight and number of single ear, 1 000- kernel weight and yield. 【Conclusion】 The planting density had significant effects on the florets differentiation, silking progress, number of florets and kernels, maize ear-axis structure and yield. The yield was the highest at the planting density of 75 000 plants/hm2.

Key words: planting density')">planting density, maize ear, development, yield