益生真菌在橘小实蝇规模化扩繁中的应用潜力

The potential application of probiotic fungi for the large-scale propagation of Bactrocera dorsalis

【目的】葡萄汁有孢汉逊酵母Hanseniaspora uvarum是存在于橘小实蝇Bactrocera dorsalis肠道的共生有益真菌,本研究通过改变饲料中酵母浸粉、麦麸和H.uvarum菌液的配比,筛选获得最优的橘小实蝇幼虫的饲料配方,为橘小实蝇规模化扩繁提供理论基础。【方法】利用响应面法(Response surface methodology,RSM)设计人工饲料中酵母浸粉、麦麸与H.uvarum的配比,统计取食不同配比的饲料后橘小实蝇幼虫的发育历期、蛹重和成虫羽化率,并计算每种饲料配方的成本;根据实验结果进行配方优化,预测取食最优配方饲料幼虫的发育历期、蛹重、成虫羽化率以及成本节约的百分比,同时,采用预测的最优饲料配方饲喂幼虫,统计取食最优饲料配方幼虫的发育历期、蛹重以及成虫羽化率,验证优化模型下的预测值与试验结果的相符性。【结果】饲料中酵母浸粉、麦麸和H.uvarum成分之间的拮抗或协同作用显著影响幼虫的发育历期、蛹重和成虫羽化率(P<0.0001)。在饲料中添加H.uvarum菌液,可以减少酵母浸粉的添加量,并降低饲养成本。通过响应面法模型预测,获得最优的橘小实蝇饲料配方比例:每份人工饲料(375 g)包括酵母浸粉3.13 g、麦麸87.45 g、H.uvarum菌液4.42 g、玉米粉40 g、蔗糖40 g及水200 mL。与传统饲料费用相比,每份人工饲料可节省成本2.35元,三组分(酵母浸粉、麦麸和H.uvarum菌液)的成本节约百分比为74.35%。采用最优饲料配方饲喂的幼虫发育历期为8.76 d,比预测值缩短了0.8 d,蛹重为13.85 mg,羽化率为93.76%,与预测值没有显著性差异。【结论】响应面法设计优化饲料配方具有一定的可靠性,葡萄汁有孢汉逊酵母H.uvarum在橘小实蝇的规模化扩繁中具有一定的应用潜力。

[Objectives]To determine the optimal larval feed formula for Bactrocera dorsalis by changing the ratio of yeast,wheat bran and Hanseniaspora uvarum(a symbiotic,beneficial fungus that lives in the intestines of B.dorsalis)in the diet,and thereby improve the large-scale propagation of B.dorsalis.[Methods]Response Surface Methodology(RSM)was used to design the ratio of yeast:wheat bran:H.uvarum,in an artificial diet.The developmental duration of larvae,pupal weight and the adult emergence rate of B.dorsalis raised on each diet were then measured and compared,and the cost of each diet calculated.An optimal diet was developed based on the results,and the development duration of larvae,pupal weight,adult emergence rate,and the cost saving potentially achieved by feeding larvae this diet,predicted.Larvae were then fed the optimal diet and their developmental duration,pupal weight and adult emergence rate compared to the predicted values.[Results]The antagonistic,or synergistic,effects of yeast,wheat bran and H.uvarum significantly affected the duration of the larval period,pupal weight and adult emergence rate(P<0.0001).Adding H.uvarum to the diet reduced the amount of yeast and thereby the cost.The optimal larval feed formula predicted by the RSM model for a single batch of artificial feed(375 g)included 3.13 g of yeast,87.45 g of wheat bran,4.42 g of H.uvarum liquid,40 g of corn meal,40 g of sucrose and 200 mL of water.The artificial diet is 2.35 yuan cheaper than the conventional diet,and the percentage cost saving for the three main components(yeast,wheat bran and H.uvarum)is 74.35%.The development of larvae fed the optimal diet was 8.76 d,0.8 d shorter than the predicted value,the average pupal weight was 13.85 mg and the adult emergence rate was 93.76%.There was no significant difference between the predicted and actual values obtained using the optimal diet.[Conclusion]RSM is a useful tool for optimizing feed formulae.Incorporating the fungus H.uvarum into the artificial diet has the potential to both improve,and reduce the cost of,the large-scale,commercial propagation of B.dorsalis.