不同磷水平土壤上磷启动肥对玉米生长效应的研究

Effects of phosphorus starter fertilizer on maize growth in soils with different phosphorus levels

探究不同磷水平土壤施用磷启动肥对玉米生长和磷吸收的影响,为玉米生产中合理施用磷启动肥提供理论依据。通过两因素盆栽试验,人工设置3个土壤磷肥力水平,分别为低磷土壤(LP,P 2.47 mg/kg)、中磷土壤(MP,P 12.35 mg/kg)、高磷土壤(HP,P 33.67 mg/kg),并分别设置施磷启动肥(SF)和不施磷启动肥处理(NS),共6个处理。于玉米七叶期时测定生长相关指标。结果表明,LP水平的株高、茎粗、叶片数、叶片净光合速率、不定根轴根总根长、地上部和地下部根系的干物质和吸磷量较MP和HP水平分别显著降低了42.95%~42.98%、49.59%~51.30%、7.32%~9.52%、45.82%~46.84%、37.44%~40.05%、84.81%~84.87%、75.03%~76.02%、83.70%~83.80%、71.86%~72.83%,可以看出土壤磷水平显著影响玉米早期发育。在LP和MP水平下,SF处理的玉米茎粗、叶面积、不定根轴根总根长、地上部和地下部的干物质和吸磷量较NS处理分别显著增加了14.74%~69.59%、22.58%~140.16%、7.16%~57.27%、12.17%~218.39%、12.10%~193.98%、11.01%~186.13%、25.10%~247.21%,其中SF处理在LP水平下对玉米生长的促进效应优于MP水平。在LP和MP水平下,SF处理较NS处理均显著增加了玉米不定根轴根总根长,但对单位不定根轴根长无显著影响。在低磷和中磷水平下施用磷启动肥可促进玉米生长和磷吸收,这对不同磷水平土壤中合理施用磷启动肥提供了理论依据。

The objective of this study was to examine the effects of phosphorus starter fertilizer on maize development and phosphorus uptake in soils with different phosphorus levels in order to develop a theoretical basis for the rational application of phosphorus starter fertilizer.Three soil phosphorus levels were set up:low phosphorus soil(LP,P 2.47 mg/kg),medium phosphorus soil(MP,P 12.35 mg/kg)and high phosphorus soil(HP,P 33.67 mg/kg),respectively;and phosphorus starter fertilizer(SF)and without phosphorus starter fertilizer(NS)were set up under each soil phosphorus level,making a total of six experimental treatments.The growth-related indicators were determined at the seven-leaf stage of maize.The results showed that the maize plant height,stem diameter,leaf number,net photosynthetic rate of leaves,total root length of adventitious axial roots,dry weight and phosphorus uptake of shoot and root at LP level were significantly reduced by 42.95%~42.98%,49.59%~51.30%,7.32%~9.52%,45.82%~46.84%,37.44%~40.05%,84.81%~84.87%,75.03%~76.02%,83.70%~83.80%,71.86%~72.83%,respectively,compared with those at MP and HP levels.Therefore,the level of soil phosphorus significantly affected the early development of maize.Under the LP and MP levels,the maize stem diameter,leaf area,total root length of adventitious axis roots,shoot and root dry weight and phosphorus uptake of SF treated maize were significantly higher than those of NS,increasing by 14.74%~69.59%,22.58%~140.16%,7.16%~57.27%,12.17%~218.39%,12.10%~193.98%,11.01%~186.13%,25.10%~247.21%,respectively.Furthermore,the favorable effect of SF treatment on maize growth was greater at the LP level than at MP level.SF treatment significantly enhanced the total root length of maize adventitious axis root at the LP and MP levels as compared to NS treatment,but had no significant effect on the root length of unit adventitious axis root.The use of phosphorus starter fertilizer at low and medium phosphorus levels can improve maize growth and phosphorus uptake,providing a theoretical basis for the rational use of phosphorus starter fertilizer in soils with varying phosphorus levels.