播期对吉林春玉米生长发育及产量形成的影响

2010～2011年在吉林省梨树县进行春玉米5个播期试验(SE、E、M、L、SL为2010年4月21日、5月2日、5月13日、5月23日及6月2日播期，2011年为4月20日、4月30日、5月10日、5月20日及6月1日播期)，探讨播期对吉林春玉米生长发育和产量形成的影响。结果表明,播期对春玉米生长发育及产量形成均有显著的影响。随播期推迟，春玉米生育期缩短；相对于SE和SL处理，M处理下叶面积指数较高且维持天数较长，有利于春玉米光合作用以及干物质积累；播期对春玉米地上干物质积累的影响表现为SE与M处理间差异不大，SL与SE、M处理相比干物质积累明显降低。试验播期范围内播期对产量影响显著，随播期的推迟呈现先升高后降低的趋势；百粒重在SE、E和M处理间无差异，与前3个播期相比，由于灌浆期缩短导致L和SL处理的百粒重显著下降；穗粒数与开花-子粒形成期内降水量呈显著负相关。本试验在2010年M处理下获得最大产量(11490.6 kg/hm2)，吉林西南部春玉米播期在5月中旬左右较为适宜。

Effect of Sowing Date on the Growth,Development and Yield Formation of Spring-maize in Jilin Province

The experiments with five sowing-date treatments(SE,E,M,L,SL were April 21,May 2,May 13,May 23 and June 2 in 2010 and April 20,April 30,May 10,May 20 and June 1 in 2011) of spring maize in 2010-2011 were conducted at Lishu county in Jilin province.The effects of sowing date on the growth,development and yield formation were studied.The results showed that the sowing dates had a significant impact on the growth,development and yield formation of spring maize.Compared with the SE and SL treatments,day number of leaf area index with relatively higher value under M treatment was longer,which is beneficial for the photosynthesis and dry matter accumulation of spring maize.The comparison of above-ground dry matter accumulation under different treatments showed that there was little difference between SE,E and M treatments,however,that of L and SL was lower than SE,E and M treatments.Within the range of sowing dates,maize yield increased firstly and then decreased with the sowing dates postponing.The kernel weight under L and SL was lower than that of SE,E and M treatments due to shorter grain-filling period.There was a significant negative correlation between the precipitation during the flowering and grain formation period and the grains per spike.Maximum yield(11 490.6 kg/ha) could be obtained under M treatments in 2010.Therefore,the appropriate sowing date of spring maize in southwestern Jinlin province was recommended to be arranged in middle May.