热研2号柱花草接种不同根瘤菌最适钼浓度的研究

为明确热研2号柱花草(Stylosanthes guianensis‘Reyan No.2’)接种不同根瘤菌达到最佳共生效果的钼浓度,采用双因子随机区组设计,在砂培中对接种3株不同根瘤菌的柱花草进行7个钼浓度的处理,通过对柱花草鲜质量、株高增加、植株含氮量、根瘤数和固氮酶活性的测定及分析,结合主成分分析确定钼对共生体系的影响。结果表明:钼对热研2号柱花草接种不同根瘤菌后结瘤数的影响不大,主要通过影响根瘤固氮酶活性从而影响柱花草株高和鲜质量;接种不同菌株的最适钼浓度存在差异,接种菌株RJS9-2的最适钼浓度为1 000~1 500 mg·L~(-1),接种YM11-1的最适钼浓度为1 000~2 000 mg·L~(-1),接种菌株PN13-3的最适钼浓度为2 000~2 500 mg·L~(-1)。

Analysis of Optimum Molybdenum Concentrations in a Symbiotic System of Stylosanthes guianensis'Reyan No.2'Inoculated with Different Rhizobium Strains

To understand the effect of different molybdenum concentrations on interaction of Stylosanthes guianensis'Reyan No.2'with different rhizobium symbiotic system,two-factor randomized block design were arranged in this experiment,and the Stylosanthes seedlings inoculated with three rhizobium strains were planted in pots filled with sand containing seven different molybdenum concentrations.They were determined in terms of dry weight,plant height,plant nitrogen content,nodule numbers and nitrogenase activity to evaluate the effect of molybdenum on the syntaxial system by princioal components analysis.The results showed that molybdenum had little effect on nodule numbers of S.guianensis'Reyan No.2'inoculated with different rhizobium strains,but on the plant height and fresh weight mainly due to the effect of molybdenum on nitrogenase activity.The optimal molybdenum concentrations for different rhizobium strains were different.The optimal molybdenum concentrations for RJS9-2,YM11-1 and PN13-3 were 1 000-1 500 mg · L-1,1 000-2 000 mg · L-1 and 2 000-2 500 mg · L-1,respectively.