Ferreira-Pinto M M, Moura-Guedes M C, Barreiro M G, Pais I, Santos M R, Silva M J
ECO-BIO, Instituto de Investigação Científica Tropical (IICT), Apartado 3041, PT-1301-901 Lisboa, Portugal.
Commun Agric Appl Biol Sci. 2006;71(3 Pt B):973-8.
The blue mold of "Rocha" pear caused by Penicillium expansum is an important postharvest disease which is adequately controlled by application of synthetic fungicides. In recent years, strategies like biological control have been considered a desirable alternative to chemicals. Several studies have demonstrated the potential of the yeast-like fungus Aureobasidium pullulans for control of postharvest decay of pear. A Portuguese isolate of Aureobasidium pullulans was characterized and evaluated for its activity in reducing postharvest blue mold decay of "Rocha" pear caused by Penicillium expansum. Study of optimal conditions for antagonist growth was carried out in six different culture media. The effect of four maturity stages of fruits in the development of A. pullulans was also studied. Biocontrol studies were performed with two concentrations of the antagonist (3 x 10(8) and 4 x 10(9) CFU/ml). A. pullulans growth was significantly different (P < or = 0.001) according to the various media and time of incubation. Best results were obtained in Corn Meal Agar (CMA) and Potato Dextrose Agar (PDA) media which contains the higher concentration of glucose (20 mg/l). Medium resulted from fruits of the first harvest date presented lower colony diameter. Inoculation of A. pullulans at 3 x 10(8) and 4 x 10(9) CFU/ml reduced the incidence of the disease by 23 and 63%, and reduced the lesion diameter by 36 and 46%, respectively.
由扩展青霉引起的“罗查”梨青霉病是一种重要的采后病害，使用合成杀菌剂可对其进行有效控制。近年来，生物防治等策略被认为是化学防治的理想替代方法。多项研究已证明类酵母真菌出芽短梗霉在控制梨采后腐烂方面具有潜力。对一株葡萄牙分离的出芽短梗霉进行了特性鉴定，并评估了其对扩展青霉引起的“罗查”梨采后青霉病腐烂的防治活性。在六种不同的培养基中研究了拮抗菌生长的最佳条件。还研究了果实四个成熟阶段对出芽短梗霉生长发育的影响。使用两种浓度的拮抗菌（3×10⁸和4×10⁹CFU/ml）进行了生物防治研究。根据不同的培养基和培养时间，出芽短梗霉的生长存在显著差异（P≤0.001）。在含有较高葡萄糖浓度（20mg/l）的玉米粉琼脂（CMA）和马铃薯葡萄糖琼脂（PDA）培养基中获得了最佳结果。首次收获日期果实制成的培养基菌落直径较小。以3×10⁸和4×10⁹CFU/ml接种出芽短梗霉分别使发病率降低了23%和63%，病斑直径分别减小了36%和46%。
