不同磷钾肥配施对冬小麦根系形态特征和生理活性的影响

Effects of Different Phosphorus, Potassium Fertilizer Combined Application on Morphology and Physiological Activity of Winter Wheat Root

以冬小麦(Triticum aestivum Linn.)品种洛旱6号为供试材料,通过盆栽试验,在3个供磷水平和2个供钾水平下,分析了不同磷、钾肥配施对冬小麦根系形态特征和生理活性的影响。结果表明,适当增施磷钾肥有利于提高次生根条数、根干重、根体积、根系活力以及根系可溶性糖含量。不同磷钾肥处理显著影响根系的形态特征和生理活性。各指标均以P2K2处理表现最好,P1K1处理表现最差。挑旗期后,P2K2处理与P1K1处理的次生根条数差异达极显著水平(P<0.01);子粒形成期后,P2K2处理的单株根干重和根体积显著大于P1K1处理(P<0.05);生育前期,P2K2处理的根冠比显著高于P1K1处理(P<0.05)。就根系生理活性而言,根系活力和根系可溶性糖含量均在拔节期达最大值,与P1K1处理相比,P2K2处理的根系活力和根系可溶性糖含量均显著增加(P<0.05)。研究表明,一定范围内,增施磷、钾肥可以促进根系的良好发育;当土壤中磷素亏缺时,增施钾肥可有效改善根系生育状况。

The morphology and physiological activity of winter wheat （Triticum aestivum Linn.） of Luohan No.6 at three phosphorus levels and two potassium levels were studied in pot experiment. The results showed that the counts of secondary roots, dry root weight, root volume, root activity, and soluble sugar content of root increased with the increase of phosphorus and potassium in a certain range. The effects of different phosphorus and potassium levels on morphology and physiological vigor of root were significant. The indicators of P2K2 were performed better than those of the others. The P1K1 was the worst. After flagging, the difference of the counts of secondary root was extremely significant between P2K2 and P1K1 （P〈0.01）. After grain formation, the dry weight of root and root volume per plant of P2K2 was extremely significantly greater than that of P1K1 （P〈0.05）. At early stage, the root shoot ratio of P2K2 was significantly higher than that of P1K1. In terms of root physiological activity, the values of the root activity and root soluble sugar content of P2K2 were significantly bigger than that of P1KI（P〈0.05）, with the values reaching maximum at jointing stage. Within a certain limit, the quality of root growth and development improved with the increase of phosphorus and potassium. When the phosphorus was deficit, the root development was improved by increasing the potassium.