喷施不同叶面肥对棉花前期生长发育和养分吸收的影响

为探索棉生长前期合理施用叶面肥的方法,研究了喷施不同质量浓度及配比尿素、硝酸铵和磷酸二氢钾对棉花前期生长发育和养分吸收的影响。结果表明,相比于对照(喷施清水),喷施叶面肥可加快植株生长速率,提高生物量积累量,增大叶面积。苗期喷施10 g/L尿素处理的棉株生长状况优于喷施等氮含量硝酸铵处理的棉株,但蕾期两处理差异不显著。根据喷施尿素质量浓度与棉株总干质量的函数关系,获得苗期最佳喷施尿素质量浓度为11.1 g/L,蕾期理论最佳喷施尿素质量浓度为49.1 g/L;虽然单一喷施5 g/L磷酸二氢钾效果逊于喷施10 g/L尿素,但是二者配合喷施效果最佳。综上,棉花前期配合喷施10 g/L尿素+5 g/L磷酸二氢钾的叶面肥能够为棉株生长提供更多的养分,增大光合面积,提高光能利用率,促进生长,为后期开花结铃奠定良好的物质基础。

Effect of Spraying Different Foliar Fertilizers on Cotton Plant Growth and Nutrient Absorption at Early Stage

The cotton plant growth and nutrient absorption after spraying different concentrations of urea, ammonium nitrate or potassium dihydrogen phosphate at early stage were studied,to explore the rational application method of foliar fertilizers at early stage of cotton. The results indicated that the cotton plant growth rate,biomass and leaf area were significantly higher in the spraying foliar fertilizer treatments than the control treatment(spraying water). In seedling stage,compared with the spraying ammonium nitrate treatment,the growth status of the cotton plant was better in spraying 10 g/L urea treatment, but there were no significant differences in budding stage between these two treatments. The correlation function indicated that the optimal spraying concentration of urea was 11. 1 g/L at seeding stage,and 49. 1 g/L at budding stage. In addition,there was better effect with the combining application of 10 g/L urea and 5 g/L potassium dihydrogen phosphate on the cotton plant. In conclusion,it could provide adequate nutrients, increase leaf area and light utility efficiency by combining application of 10 g/L urea and 5 g/L potassium dihydrogen phosphate on the cotton plant at early stage.