不同质地土壤上玉米养分吸收和分配特征

采用池栽试验在4种质地土壤和2种施肥水平下,研究了玉米植株氮、磷、钾的吸收和分配特征。结果表明,不同质地土壤上玉米植株养分累积量为氮钾磷;不同处理玉米氮、磷、钾的累积量表现为中壤轻壤粘壤砂壤,且各处理间差异达显著水平。不同处理叶片和茎鞘中三元素累积量的变化与单株一致,氮、磷、钾分配以叶片中的比例略高于茎鞘。从后期氮、磷、钾的转移率看,不同质地土壤表现为砂壤轻壤中壤粘壤;不同处理中子粒中氮、磷、钾的含量与产量变化一致,且处理间达显著水平。施肥增加了各种质地土壤上玉米植株及器官氮、磷、钾的累积量和子粒产量,其中砂壤增加幅度最大,轻壤和中壤次之,粘壤最小。同时施肥使得叶片和茎鞘中的氮、磷、钾转移率略有降低。

Characteristics of nutrient absorption and distribution of maize under different soil textures

Soil texture is an important soil physical property influencing nutrient absorption and distribution,and thus maize growth.A pool-culture experiment with four soil textures(sandy loam,loam,loamy clay and clay loam) and two levels of fertilizations(with and without fertilizer) were conducted for two years to study the characteristics of nutrient absorption and distribution in maize plant.The area of each pool was one square meter with six plants inside.Corn(Yedan22) was planted on June 7 and harvested on September 17 in both years.N was applied at 75kg/ha and 150 kg/ha at jointing stage and male tetrad stage,respectively.At the beginning of maize growth,P was applied at 50kg/ha.The results showed the order of nutrient accumulation was N>K>P.The absorption and distribution of N,P and K differed with soil textures,and the order of total absorption of N,P and K per corn was loamy clay >loam> clay loam >sandy loam.Statistical analysis indicated that there was significant difference among these soil textures.The order of N,P and K consumption in leaves and culm-sheath agreed with that in plant,and the proportion of distribution in leaves was a little higher than that in the culm-sheath.In the late growing stage,the transferring rate of N,P and K followed the order of sandy loam>loam> loamy clay > clay loam.Yield and nutrient accumulation in grain were highest in loamy clay and lowest in sandy loam.Yield and accumulation of N,P and K were increased the most by fertilization in sandy loam,followed by loam,loamy clay and clay loam.