寡雄腐霉发酵液的动物毒性及其对柑橘果实贮藏期青、绿霉病的防治效果

Toxicity of Pythium oligandrum broth to animal and its control effect on rot diseases caused by Penicillium italicum and Penicillium digitatum in orange fruit storage

摘要:

摘要:【目的】研制安全、无毒、高效的生物保鲜剂，降低意大利青霉(Penicillium italicum，青霉)和指状青霉(Penicillium digitatum，绿霉)引起的柑橘烂果。【方法】试验利用自主选育的寡雄腐霉优良菌株(Pythium oligandrum CQ2010)，制备发酵液，测试了对小鼠的急性毒性，并设置对照(液体培养基，CK)、寡雄腐霉发酵液(P． oligandrum Broth，POB)、咪鲜胺(Prochloraz，PC)、咪鲜胺+ POB(PC+POB)等4种处理，研究了它们对青、绿霉菌的抑制作用及其对柑橘防腐保鲜的作用。【结果】用大剂量的POB灌胃给药对小鼠体重增长无显著影响，供试动物的外观和行为均无异常，心、肝、肾、肺、肠等组织器官也未见病理改变。POB显著抑制青、绿霉菌丝生长和孢子萌发，抑制率分别为70.24%－93.74%(菌丝生长)和44.91%－87.82%(24 h孢子萌发)。柑橘果实接种青霉后，烂果率CK＞POB、PC＞PC+POB，防治效果PC+POB＞POB、PC。在模拟柑橘商品化贮藏保鲜试验中，青、绿霉发病率占总发病率的50%以上，CK、POB、PC和PC + POB的烂果率依次为26.40%、15.03%、16.61%和4.21%。此外，POB对果实品质无显著影响，但显著提高果皮中的超氧化物歧化酶、过氧化物酶和过氧化氢酶活性，有益于提高柑橘果实的抗病性和贮藏性。【结论】在柑橘贮藏过程中，POB对果实青、绿霉病有显著的防治作用，并与咪鲜胺的防病效果有叠加作用。

Abstract:

Abstract:［Objective］In order to develop a safe，nontoxic and efficient biological antistaling agent and to decrease the incidence of rot diseases caused by the Penicillium italicum and Penicillium digitatum in orange fruit storage，［Methods］the present experiment was carried out with Pythium oligandrum broth (POB) produced by our self- isolated strain (P．oligandrum CQ2010) to study the toxicity to animal． Thereafter，mycelium growth and spore germination of both P．digitatum and P． italicum and control effect of rot disease in orange storage were compared after treated by liquid culture medium (control)，POB，prochloraz (PC)，and PC+POB.［Results］Gastric lavage with large amount POB did not influence mouse weight． The animals also showed no abnormality in appearance，behaviors and pathology changes in heart，liver，kidney，lung and intestine． POB decreased the hyphal growth by 70.24%－93.74% and spore germination by 44.91%－87.82% (24 h after POB addition) of these two pathogenic fungi． Disease incidence of orange fruit following P.italicum inoculation changed in the sequence: CK＞POB＞PC＞PC+POB and the control efficacy behaved otherwise．In commercial simulation storage，the disease incidence of orange fruit caused by P．digitatum and P．italicum was above 50% of the total．The fruit rot rate was 26.40% (CK)，15.03% (POB)，16.61% (PC) and 4.21% (PC+POB)．There were no significant differences in fruit quality under different treatments.［Conclusion］POB was safe to animal and could decrease rot disease incidence caused by P. italicum and P. digitatum in orange storage whereby producing a positive interaction with prochloraz and controlling rot diseases caused by these two fungi.