Wang Yifei, Bao Yihong, Shen Danhong, Feng Wu, Yu Ting, Zhang Jia, Zheng Xiao Dong
Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310029, People's Republic of China.
Int J Food Microbiol. 2008 Apr 30;123(3):234-9. doi: 10.1016/j.ijfoodmicro.2008.02.002. Epub 2008 Feb 15.
The basidiomycetous yeast Rhodosporidium paludigenum Fell & Tallman isolated from the south of East China Sea was evaluated for its activity in reducing postharvest decay of cherry tomatoes caused by Alternaria alternata in vitro and in vivo tests. The results showed that washed cell suspension of R. paludigenum provided better control of A. alternata than any other treatment, while the autoclaved cell culture failed to provide protection against the pathogen. The concentration of antagonist had significant effect on biocontrol effectiveness in vivo: when the concentration of the washed yeast cell suspension was used at 1 x 10(9)cells/ml, the percentage rate of black rot of cherry tomato fruit was only 37%, which was remarkably lower than that treated with water (the control) after 5days of incubation at 25 degrees C. Furthermore, a great biocontrol efficacy of R. paludigenum was observed when it was applied prior to inoculation with A. alternata: the longer the incubation time of R. paludigenum, the lower disease incidence would be. However, there was little efficacy when R. paludigenum was applied after A. alternata inoculation. In addition, on the wounds of cherry tomato, it was observed that R. paludigenum grew rapidly increasing 50-fold during the first 12h at 25 degrees C. To the best of our knowledge, this is a first report concerning that the marine yeast R. paludigenum could be used as a biocontrol agent of postharvest fungal disease.
对从中国东海南部分离出的担子菌酵母沼泽红冬孢酵母（Rhodosporidium paludigenum Fell & Tallman）在体外和体内试验中减少链格孢（Alternaria alternata）引起的樱桃番茄采后腐烂的活性进行了评估。结果表明，沼泽红冬孢酵母的洗涤细胞悬液对链格孢的防治效果优于其他任何处理，而高压灭菌的细胞培养物未能提供对该病原菌的保护。拮抗菌浓度对体内生物防治效果有显著影响：当洗涤后的酵母细胞悬液浓度为1×10⁹个细胞/毫升时，樱桃番茄果实的黑腐病发生率仅为37%，在25℃下培养5天后，显著低于用水处理（对照）的情况。此外，在接种链格孢之前施用沼泽红冬孢酵母时观察到了很好的生物防治效果：沼泽红冬孢酵母的培养时间越长，发病率越低。然而，在接种链格孢后施用沼泽红冬孢酵母时效果甚微。此外，在樱桃番茄伤口上观察到，沼泽红冬孢酵母在25℃下培养的前12小时内迅速生长，数量增加了50倍。据我们所知，这是关于海洋酵母沼泽红冬孢酵母可作为采后真菌病害生物防治剂的首次报道。
