Abstract: To clarify the receptivity and senescence of maize silks under high stand density,two cultivars Denghai 605(DH605)and Zhengdan 958(ZD958)were used to analyze the effects of different plant densities(52 500,112 500 plant/ha)on silk receptivity and silk senescence in maize. The results showed that the silk growth rate was decreased at high stand density,result in the duration of silk emergence and silk receptivity for the entire ear were delayed,but the aging process of silk was not affected after silk emergence. Compared with low stand density,the duration of silk emergence and silk receptivity for the entire ear at high stand density were lengthened 3 and 2 days for DH605,respectively,and 1 and 1-2 days for ZD958,respectively. Although,apical silk emergence in maize ear was late,it still had receptivity under high stand density. Further analysis showed that the negative correlation coefficient between percentage of silk receptivity and silk senescence based on the data of synchronous pollination at varying days from 1 to 20 days after first silk emergence was significant(r²=0.964^***). Hence,silk senescence was the primary cause of silk receptivity decreased due to the delay of pollination after silk emergence.In general,the senescence process of silk was not affected at a high stand density,but lengthened the duration of silk receptivity for entire ear.

Key words: Maize, Silk, Growth and senescence, Receptivity, Plant density

CLC Number: 

• S513.01