植物生长促生菌对盐胁迫下水稻种子萌发及幼苗生长的影响

Effects of Plant Growth-promoting Rhizobacteria (PGPR) on the Rice Germination and Seedling Development under Salt Stress

JT-5是从水稻根际土壤中分离得到的1株植物生长促生菌。在不同浓度盐(氯化钠)溶液的胁迫下,JT-5对水稻种子的萌发、幼苗的生长发育有显著的促进作用。水稻种子经菌株JT-5处理后,在第三天的发芽势显著地提高。在盐浓度为50、75、100、125 mmol/L时,JT-5处理组水稻种子的发芽势分别为84.44%、92.22%、80.00%和84.44%,而相应的对照组仅为68.89%、54.44%、35.56%和17.78%;同样浓度的盐胁迫下,JT-5能够有效地促进水稻幼苗根长和苗高的生长,分别比对照处理组的根长长10～90 mm和苗高高10～40 mm;JT-5处理组水稻的不定根数多于对照组1.0～2.6条;经JT-5处理后的优势均随盐溶液浓度的增加呈扩大趋势;苗干重和根的含水量(占鲜重)均高于对照组。

The bacteria JT-5 was isolated from the soil around rice roots.It could significantly prompt the germination of rice seeds and their development under the stress of different concentration of salt solution （NaCl）.The germination energy of rice seeds was strongly promoted on the third day when it was treated with JT-5.The germination energy was 84.44%,92.22%,80.00% and 84.44% corresponding the concentration of salt solution 50,75,100 and 125 mmol / L,respectively.While in control groups,the germination energy was 68.89%,54.44%,35.56% and 17.78%.Also,It was found that JT-5 could effectively prompt the growth of rice seedlings and their roots.The roots length were 10～90 mm longer than that of the control group;and the rice seedlings height were 10～40 mm longer than that of the control group.Meanwhile,the amount of lateral roots in the JT-5 treatment group also was 1.0 to 2.6 more than the control group.Moreover,the trendency of preponderance with JT-5 was stronger in correpondence to the concentration of salt solution;the dry weight and water content （in fresh weight） in roots were higher than the control group.