3株拮抗酵母菌对苹果采后青霉病的防治效果

在活体和离体条件下,采用刺伤苹果接种酵母菌的方法,研究了3株拮抗酵母菌对扩展青霉(Peni-cillium expansum)引起的苹果采后病害的防治效果。结果表明,3株酵母菌孢子悬浮液对青霉病防治效果显著,防效达80%~96%;3株酵母菌可以在苹果果实伤口处接种后的前3 d快速定殖,在之后的5 d保持稳定;在PDA对峙培养中,酵母菌不能抑制病菌的生长,而在其液体培养中,酵母菌孢子悬浮液能显著抑制青霉病菌孢子的萌发,其上清过滤液和灭菌液不能抑制果实的腐烂,表明其作用机制主要是营养和空间竞争。

Biocontrol efficacy of three yeast isolates on postharvest blue mold of apple caused by Penicillium expansum

The efficacy of three yeasts isolates on control of postharvest apple diseases caused by Penicillium expansum in vivo and in vitro was studied by wounding inoculation.The results showed that significant control was achieved with a washed cell suspension,and the biocontrol efficacy varied from 80% to 96%.Rapid colonization of the three yeast isolates in wounds was observed during the first 3 days,and remained stable 5 days after incubation.In the tests on potato dextrose agar plates,agar disks of the three yeast isolates streaked onto PDA plates seeded with pathogen in the centre did not inhibit the pathogen growth,the spore germination of P.expansum,however,was significantly inhibited by the yeast cell suspensions.Treatments of wounds with autoclaved cell cultures or cell-free culture filtrate did not prevent decay,suggesting that the main action mode of the yeast isolates was the competition between nutrient and space.