播期对吉林中部春玉米产量形成及氮素分配的影响

本实验设置3个播种日期，对比研究不同播种日期对两个玉米品种产量、生物量、氮素积累和分配特征的影响。结果表明，XY335在早播和晚播处理下，产量比中播处理分别提高11.5%和5.1%;ZD958在早播和中播处理下，产量较晚播分别提高15.8%和11.1%。在VT-R6期，XY335的干物质积累和氮素积累早播和晚播较中播分别提高6.8%和2.7%、31.5%和11.4%,ZD958的干物质和氮素积累早播和中播较晚播分别提高26.6%和25.9%、99.2%和59.4%。在早播处理下，XY335、ZD958具有较高的花后干物质和氮素分配，分别达到了58.5%和63.2%、49.1%和52.2%。在公主岭地区，两个品种均适宜早播，但XY335播期范围更广，适宜播期均通过提高VT-R6期的干物质积累和氮素积累而提升产量。

Effects of Sowing Date on Yield Formation and Nitrogen Distribution of Spring Maize in Central Jilin Province

In this experiment,three sowing dates were set to study the effects of different sowing dates on yield,biomass,nitrogen accumulation and distribution characteristics of two maize varieties.The results showed that the yield of XY335 was increased by 11.5% and 5.1% in early sowing and late sowing compared with the middle sowing,and ZD958 was increased by 15.8% and 11.1% in early sowing and middle sowing compared with late sowing.In VT-R6 stage,the dry matter and nitrogen accumulation of XY335 in early sowing and late sowing have increased by 6.8% and 2.7%,31.5% and 11.4%,respectively,compared with middle sowing.While dry matter and nitrogen accumulation of ZD958 in early sowing and middle sowing increased by 26.6% and 25.9%,99.2% and 59.4%,respectively,compared with late sowing.In early sowing,both of XY335 and ZD958 had higher distribution rates of dry matter and nitrogen after anthers,reaching 58.5%,63.2%,49.1% and 52.2%,respectively.In Gongzhuling,all these two varieties were suitable for early sowing,but XY335 was more adaptability,and the yield was improved by increasing dry matter accumulation and nitrogen accumulation at VT-R6 stage.