安徽沿江地区露地鲜食玉米适宜播期确定

Determination of the Suitable Sowing Date of Fresh Maize Along the Yangtze River of Anhui Province

以鲜食玉米“彩甜糯100”为材料,设置4月1、16日,5月1、16、31日,6月15、30日,7月15、30日和8月14日共10个播期,研究不同播期鲜食玉米的生育期、产量和产值及其与气象因子的关系,以明确安徽省沿江地区露地播种条件下鲜食玉米的适宜播期。结果表明:(1)随播期推迟,鲜食玉米生育期呈长-短-长变化趋势,株高、秸秆鲜重及产量表现为高-低-高,穗粒数呈多-少-多变化趋势。4月1日-5月1日和7月30日播期的鲜食玉米平均产量为20026.56kg·hm^(-2),显著高于其他播期处理(P<0.05);7月30日播期处理直接销售鲜穗产值为70245.00元·hm^(-2),较其他处理显著增加68.66%~123.50%(P<0.05)。(2)5月31日-7月15日播种鲜食玉米,生育期内≥32℃日数占全生育期日数的56.25%~60.26%,高温积热较4月1日-5月1日和7月30日播期处理高47.78%~54.46%;5月31日-7月15日播种鲜食玉米生育进程加快,株高降低,物质积累减少,产量降低。8月14日播种鲜食玉米,受灌浆期低温影响,鲜食玉米无法正常成熟收获。(3)鲜食玉米生育期与播种-吐丝期日平均气温呈显著负相关关系;气象因子与鲜食玉米产量的相关系数大小依次为播种-吐丝期>10℃有效积温、降水量、日平均气温和平均气温日较差,吐丝-成熟期降水量、>10℃有效积温以及播种-吐丝期日照时数。鲜食玉米播种-吐丝期>10℃有效积温主要通过调节穗粒数影响产量。安徽省沿江地区春季4月1日-5月1日或夏季7月30日播种鲜食玉米,可延长鲜食玉米生育期,增加鲜食玉米植株物质积累,获得高产。5月31日-7月15日播种鲜食玉米存在潜在高温风险。

A field trial was carried out along the Yangtze river in Anhui province to clarify the relationship between growth,yield of fresh maize and meteorological factors under different sowing dates,which would provide a reference to the suitable sowing date of fresh maize.In the study,the fresh maize cultivar “Caitiannuo 100” was used.The treatments consisted of ten sowing dates:April-1,April-16,May-1,May-16,May-31,June-15,June-30,July-15,July-30,and August-14.The growth period,yield,yield component and production value of fresh maize were analyzed.The results showed that the growth duration was shortened when delaying the sowing date from April-1 to June-15.When the sowing date was from June-15 to July-30,the growth duration was extended.The yield was decreased when delaying the sowing date from April-1 to June-30,and the yield was increased.The mean grain yield of fresh ear in the sowing date from April-1 to May-1 and July-30 was 20026.56kg·ha^(-1),which was significantly higher than that of other sowing dates(P<0.05).The production value of fresh ear planted in July-30was 70245.00yuan·ha^(-1),which was significantly increased by 68.66%-123.50% compared with other sowing dates(P<0.05).When the fresh maize was sowed during May-31 to July-15,the days of high temperature ≥32℃accounted for 56.25%-60.26% in the whole growth duration of the plant,and the accumulation of temperature ≥32℃ increased by 47.78%-54.46% than that of sowing dates from April-1 to May-1 and July-30,which accelerated the fresh maize growing process,shortened the plant height,declined the matter accumulation,ultimately decreased the yield.The fresh maize could not be harvested with the sowing date of August-14 due to the lower temperature during the grain filling stage.The growth duration of maize was negatively correlated with daily mean temperature before silking.The ranking of the correlation coefficients between meteorological factors and fresh maize yield from high to low were effective accumulated temperature 10℃ before silking,precipitation before silking,daily mean temperature before silking,average daily temperature range before silking,precipitation after silking,effective accumulated temperature >10℃ after silking,and sunshine hours before silking.The effective accumulated temperature >10℃ before silking stage mainly influenced the yield by regulating the kernel number per ear.In conclusion,the fresh maize sowed during April-1 to May-1 or July-30 could be prone to extend growth period,increase matter accumulation,and obtain high yield,while might be in danger in the risk of high temperature stress with the sowing date from May-31 to July-15 along the Yangtze river.