小麦丰收菌(Bacillus sp.W_(2—6))对小麦生长前期的生理效应研究

STUDIES ON THE PHYSIOLOGICAL EFFECTS OF BACILLUS SP. W_(2-6)ON THE WHEAT PLANT DURING ITS EARLY AND MID-GROWTH STAGE

小麦丰收菌(Bacillus sp.W_(2-6)能提高麦株鲜重2.23％～19.3％、干重1.03％～14.31％、叶绿素含量3.61％～38.91％、净光合速率7.26％～11.53％、CAT酶活性22.23％～79.34％。SOD酶活性在三叶期时低于对照,而拔节和孕穗期均比对照高。过氧化物酶同工酶图谱无明显差异。该菌对小麦有较强的促生作用,并有随生育进程而提高的趋势。该菌不会引起小麦的遗传变异。

In order to examine the physiological effects of Bacillus sp. W_(2-6)on wheat, measurements concerning a few physiological parameters were compared at the 3-leaf stage, stem-elongating stage and booting stagc between the plants originating from seeds treated with the bacterium suspcnsion during germination at 10~8cfu/ml before they were sown into the pots and the plants ariving from water-treated seeds (check). The treated plants gave an increment of 2.23-19.3％ in fresh weight and 1.03-14.31％ in dry weight of the above-ground parts, 3.61-38.91％ in chlorophyll content and 7.26-11.53％ in net photosynthesis rate as compared with the control. Catalase activity of the treated plants was 122.23-179.34％ that of the check (control). At the 3-leaf stage, SOD activity of the treated plants was lower than that of the check, but later, at the stem-elongating and booting stages, it was higher in the treated plants. Peroxidasc zymogram reaction showed little difTerence between the treated plants and the check, suggesting that the bacteria could not bring on any genetical change in the treated plants. Such results might indicate that Bacillus sp. W_(2-6) has a growth-promoting effect on wheat plants, which tends to strengthen gradually with the growth and development of the plant.