钾肥对提高假俭草抗寒性作用的研究

钾肥对提高假俭草Eremochloa ophiuroides抗寒性有显著作用,一方面它可显著增强SOD酶的活性,尤其是4.5～6 g/m2 K2O能极显著地增加SOD酶的活性(P＜0.01),另一方面它使相对电导率有不同程度的下降,不同施肥量处理的电导率与CK间差异都达极显著水平,并且一定量的钾肥分次施用较1次施用时的差异达显著水平(P＜0.05).同时,假俭草的电导率与SOD酶活性间存在显著负相关,适时适量地施钾肥不仅可以增强SOD酶活性,并且降低了细胞质膜的相对透性,保护了膜的完整性,从而使假俭草的抗寒性得到一定程度的提高.所以通过施钾肥提高假俭草抗寒性是可行的草坪管理技术.适宜的施肥量是6 g/m2 K2O,以少量多次施用效果最佳.

Study on the influence of potassium on cold hardiness of Centipedegrass

Potassium can significantly improve the cold hardiness of centipdegrass. On one hand, potassium can significantly strengthen the activity of SOD enzyme, especially effect of 4.5~6 g/m~2 K 2O is significant at the 0.01 level. On the other hand, potassium can decrease the relative electrolyte leakage of centipedegrass. Electrolyte leakage between different fertilization treatments and the control is significantly correlated to the SOD enzyme activity. In proper time, applying potassium with proper quantity not only strengthens SOD enzyme activity, but also decreases the relative electrolyte leakage, and protects the integration of membrane, which improves the cold hardiness of centipedegrass at a certain degree.Therefore, applying potassium is feasible management technique to improve the cold hardiness of centipedegrass. The appropriate quantity is 6 g/m~2 K 2O, and limited quantity in several applications are best.