To study dietary pH effects on Lymantria dispar asiatica larvae and provide a theoretical basis for its control in different forests, phosphate buffers (PBs) of pH 6, 7, and 8 were used to prepare experimental diets. The diet prepared with pH 6 PB was named as DPB6, with pH 8 PB as DPB8, and with pH 7 PB as DPB7 (control). The dietary pH was 5.00 in DPB6, 6.05 in control, and 6.50 in DPB8. After feeding on the diets with different pH values for 84 hr, fourth‐instar caterpillars were randomly collected. Growth and various physiological traits were determined and 16S recombinant DNA sequencing was performed using the intestinal microflora of surviving larvae. Results showed that the mortality was 30% in DPB6, and 10% in DPB8, while no mortality was observed in control. The partial least squares discriminant analyses suggested that diets prepared with PB of different pH resulted in different food intake, amount of produced feces, weight gain, digestive enzyme activities, and antioxidant enzyme activities in larvae. Interestingly, both the highest weight gain and the lowest total antioxidant capacities were seen in control larvae. Results also showed that the larval gut microbiota community structure was significantly affected by dietary pH. Moreover, linear discriminant analysis effect size suggested that the family Acetobacteraceae in control, genus Prevotella in DPB8, and genus Lactococcus, family Flavobacteriaceae, family Mitochondria, and family Burkholderiaceae in DPB6 contributed to the diversity of the larval gut microbial community.

中文翻译：

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实验饮食的pH值变化会影响亚洲香蒲幼虫及其肠道菌群的性能。

研究膳食pH值对亚洲菜蛾的影响幼虫为控制其在不同森林中提供理论依据，pH 6、7和8的磷酸盐缓冲液（PBs）用于制备实验饲料。用pH 6 PB配制的日粮命名为DPB6，用pH 8 PB命名为DPB8，用pH 7 PB命名为DPB7（对照）。饮食pH在DPB6中为5.00，在对照中为6.05，在DPB8中为6.50。以不同pH值的饮食为食84小时后，随机收集了四龄幼虫。确定生长和各种生理特征，并使用存活的幼虫的肠道菌群进行16S重组DNA测序。结果显示，DPB6的死亡率为30％，DPB8的死亡率为10％，而对照中未观察到死亡率。偏最小二乘判别分析表明，用不同pH的PB配制的饮食会导致不同的食物摄入，幼虫的粪便产生量，体重增加，消化酶活性和抗氧化酶活性。有趣的是，在对照幼虫中，增重和总抗氧化剂能力最低。结果还表明，幼虫肠道微生物群落结构受饮食pH值显着影响。而且，线性判别分析的影响大小表明，醋杆菌科在对照中属普氏菌在DPB8，和属乳酸，家庭黄杆菌，家庭线粒体和家庭Burkholderiaceae在DPB6促成幼虫肠道微生物群落的多样性。