氮、磷、钾胁迫对甘蔗生长及固氮酶活性的影响

Effects of Nitrogen, Phosphorus and Potassium Fertilization Application on Growth and Nitrogenase Activity of Sugarcane

氮、磷、钾是植物生长发育所必需的大量矿质元素,也是甘蔗与固氮微生物联合固氮系统形成的重要调控因素。本研究以粤糖93-159和ROC22为材料,在酸性土壤上进行肥效试验,分析了施用氮、磷和钾肥对甘蔗生长及固氮酶活性的影响。结果表明,不施氮肥显著抑制了甘蔗的生长发育,甘蔗株高、茎径和有效茎数与氮磷钾处理(NPK)相比,粤糖93-159降低了74.49%、17.48%、78.0%,ROC22降低了78.28%、68.75%、64.7%;然而,不施氮肥促进了甘蔗联合固氮作用,显著提高了根系和+4叶的固氮酶活性,粤糖93-159增加了25.24%、68.83%,ROC22增加了99.67%、58.97%。不施磷肥显著减少了2个甘蔗品种的有效茎数,降低了粤糖93-159的植株高度、固氮酶活性和氮浓度。不施钾肥仅影响2个甘蔗品种的固氮酶活性及粤糖93-159的有效茎数。研究结果可为挖掘甘蔗养分高效潜力及联合固氮系统与养分相关联的基础研究提供参考依据。

Nitrogen,phosphorus and potassium is not only the essential mineral nutrients for plant growth and development but also an important regulatory factor for the formation of nitrogen fixation system between sugarcane and nitrogen fixing microorganisms.An experiment was carried out to analyze the sugarcane growth and nitorgenase activity as affected by Nitrogen,Phosphorus and Potassium fertilization application with two sugarcane varieties Yuetang 93-159 and ROC22.The results showed that the growth and development of sugarcane had been inhibited with decreasing of the plant height,millable stalks and diameter compared with control(normal fertilization),Yuetang 93-159 reduced 74.49%,17.48%and 78.0%,ROC22 reduced 78.28%,68.75%and 64.7%.However,the sugarcane associated nitrogen fixation had been promoted with significantly increasing of the nitrogenase activity in roots and+4 leaves under no nitrogen fertilizer supplied,Yuetang 93-159 was increased 25.24%and 68.83%,ROC22 was increased 99.67%and 58.97%.The millable stalk of both two sugarcane varieties had been significantly restrained,and it had been reduced the plant height,nitrogenase activity and nitrogen concentration in Yuetang93-159 when no providing with phosphorus.The nitrogenase activity in both two sugarcane varieties and millable stalks of Yuetang93-159 were affected by treating with no potassium.Our results can provide the reference for exploring the potential of nutrient efficiency in sugarcane as well as the basic research on plant associated nitrogen fixation system as associated with nutrient application.