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[Objective] The present paper aimed to investigate the effects of rearing material nutrients and juvenile hormone Ⅲ (JHIII) on the growth and development of Hepialus menyuanicus larvae, and to clarify the direct and indirect relationships between rearing material nutrients and JHIII on the growth and development of larvae using through path analysis. [Method] The newly molted 3rd instar larvae were studied with coconut flour as the rearing substrate, and a two-factor experimental design was used with four rearing materials[J: (Potentilla anserina), H: (Daucus carota), Z: (Polygonum viviparum) and D: (Rheum palmatum) ]and three JHIII titer levels (B1: 13.32 μg/g, B2: 16.56 μg/g and B3: 22.76 μg/g) were reared on larvae, and the reared materials were analyzed for crude protein, crude fiber, soluble sugar, crude ash, water content, carbohydrate and JHIII on larval growth and development (head width, body length, body weight and survival rate) were analyzed by regression analysis and path analysis. [Result] Both rearing materials and JHIII significantly affected the growth and development of larvae with a significant interaction effect (P＜0.05) .Path analysis showed that JHIII had the greatest direct effect on larval head width, body length, body weight and survival rate (P=-2.56, P=-1.89, P=-3.66, P=2.36) .Crude protein had the greatest indirect promoting effect on head width and body length (P=3.99, P=3.79), soluble sugar had the greatest indirect promoting effect on body weight (P=5.40), and crude ash had the greatest indirect inhibitory effect on survival (P=-5.14), and crude protein, soluble sugar, and crude ash all had the greatest indirect effects on head width and body length, body weight, and survival through JHIII (P=2.23, P=1.64, P=2.93, P=-2.86) . [Conclusion] The paper preliminarily finds the simple mechanism of feeding materials affecting the growth and development of larvae.JHIII is a direct factor affecting the growth and development of larvae, while nutrients in rearing materials are an indirect factor and affect larval growth and development through changes in JHIII titer.The nutrients of rearing materials lead to inconsistent growth and development of larvae by affecting the JHIII titer of the larvae.Among them, crude protein, soluble sugar and crude ash promote the growth of head width and body length of larvae, promote the development of body weight and reduce the survival rate of larvae by inhibiting the JHIII titer.The study provides a scientific reference for the artificial domestication and succession rearing of H.menyuanicus. [ABSTRACT FROM AUTHOR]

【Objective】The present study aimed to obtain strains of Paecilomyces hepiali with higher combined content of biomass（dry weight, fresh weight, colony growth rate） and metabolites（polysaccharide, protein, adenosine, mannitol）.【Method】The spore suspension of strain YS-01 diluted to 10-3 concentration was placed under UVC UV lamp（30 W） at 30 cm for 40 s for mutagenesis treatment, and 20 mutagenic strains with faster colony growth, more biomass, better color and round colony shape were initially screened and named YS-A,YS-B,YS-C,YS-D,YS-E,YS-F,YS-G,YS-H,YS-I,YS-J,YS-K,YS-L,YS-M,YS-N,YS-O,YS-P,YS-Q,YS-R,YS-S,YS-T.The 21 strains were evaluated by using the gray correlation analysis.【Result】The best strain for mycelium dry mass, fresh mass, growth diameter and adenosine was YS-A（P＜0.05）; The highest strain for polysaccharide production was YS-C（P＜0.05）; The highest strain for adenosine, protein and mannitol production was YS-B（P＜0.05）.The highest biomass production strain was YS-A, and the highest metabolite production and combined production strain was YS-B. The genetic stability of dry mass, fresh mass and mycelial growth diameter was good within 10 generations for YS-A strain; The genetic stability of polysaccharide production was good within 10 generations for YS-C strain; The genetic stability of mycelial growth diameter and mannitol production was good within 10 generations for YS-B strain; The genetic stability of dry weight, fresh mass and adenosine was good within 9 generations; The genetic stability of polysaccharide production was good within 10 generations for YS-B strain. The inheritance of polysaccharide and protein was stable within 8 generations.【Conclusion】Strain YS-A can be used for strains aiming at mycelial dry mass, fresh mass, growth diameter, adenosine and biomass production; YS-C can be used for strains aiming at polysaccharide production; YS-B can be used for strains aiming at adenosine, protein, mannitol, metabolite production and combined production. [ABSTRACT FROM AUTHOR]