假单胞菌HYS菌株对油菜种子发芽的影响

Effects of Pseudomonas sp. HYS on the Germination of Rapeseed

为了研究假单胞菌HYS菌株及其上清液对油菜种子发芽的作用,采用LB培养假单胞菌HYS菌株,分别用水(CK)、LB和HYS菌液浸种油菜种子或在油菜发芽过程中分别添加这3种液体。结果表明,HYS菌液浸种不影响油菜种子最终的露白和发芽,但显著抑制油菜种子的露白和发芽进程;在油菜发芽过程中添加HYS菌液也会抑制油菜种子的露白进程,同时还抑制油菜种子的发芽和芽苗生长,而LB抑制油菜根的生长。油菜在发芽过程中,头1~2 d感染HYS菌株则显著抑制油菜种子的发芽,且感染时间越早其抑制效果越强,连续感染HYS菌株对油菜种子发芽和芽苗生长的抑制作用更强,且这种抑制作用主要在发芽的头1~3 d发挥作用。将HYS菌液离心过滤除菌,用水倍比稀释LB和上清液后培养油菜种子,发现上清液经100和1 000倍稀释后促进油菜种子的发芽。上述结果表明假单胞菌HYS菌株在油菜种子发芽和早期生长过程中不适宜用其进行生物防治,但适当稀释HYS上清液可促进油菜种子发芽和生长。

In order to study the effect of Pseudomonas sp. HYS on the germination of rapeseed,HYS bacteria were cultured in LB medium, and the rape seeds were soaked with water （control）, LB, and HYS culture liquid, respectively. The results showed that soaking seeds with HYS strain did not affect the split number and the number of shoots at last,but inhibited the splitting and shooting progress of rapeseed. HYS strain inhibited the splitting progress of rapeseed,the rape germination and the growth of rape shoot when the rapeseeds were contaminated with HYS strain during germination. LB inhibited the growth of rape root. HYS strain inhibited the rape germination when the rapeseeds were contaminated with HYS strain during germi-nation of 1~2 d,earlier contamination enhanced the inhibition effect;continuous contamination reinforced the inhibition effect. However,the inhibition effect of HYS strain occurred only during 1~3 days of rape germination. Rape seeds were cultivated by diluted LB and supernatant of HYS bacteria liquid that was treated with centrifugal filter,the results showed that 100 times or 1000 times diluents of HYS supernatant did not affect the split number of rapeseed,but accelerated rape germination and was beneficial to the growth of rape shoot. The results indicated that the Pseudomonas sp. HYS should not be used dur-ing the germination and early stage of growth in rape, however, diluted supernatant of HYS culture liquid could be used to accelerate the rape germination and promote the growth of rape shoot.