Abstract:The symbiosis of Armillaria spp. and Gastrodia elata is an interaction consequence of the infection system of Amillaria spp. and the digestive and/or antifungi system of G. elata, and this may be regulated by temperature. In order to reveal the influence of altitude on the yield and quality of Gastrodia spp., and the mechanism how increased temperature damage the symbiosis of Armillaria biological species and G. elata, this study determined the yield of G. elata cultivated at different altitudes, and the contents of the main medicinal components gastrodin and phydroxybenzyl alcohol. The symbionts of G. elata were heated up in the room, then activity of chitinase, β1, 3glucanase, phenylalanine ammonia enzyme and polyphenol oxidase were determined, as well as the inhibition effects of homogenate of the G. elata tube on Armillaria mycelial growth. Results showed that: (1) altitude had a significant effect on the yield and effective medicinal components of hybrid of G. elata B1. f. elata × G. elata B1. f. glauca, with the highest yield at 1 600 m and the highest content of effective components at 1 600 m. (2) Temperature significantly affected the antifungal system of G. elata, and the response of G. elata digestive enzymes and defense enzyme systems to temperature is different. The specific manifestation is that the digestive enzyme system activity of G. elata increases under low temperature conditions and the activity of defense enzyme system at high temperature. (3) The increase in temperature leads to a significant decrease in the inhibitory effect of G. elata tissue fluid on the mycelium of Armillaria. There may be heatinactivating factors in living G. elata that promote the growth of Armillaria. Studies have shown that the increase in temperature caused by the decrease in altitude in Gastrodia planting areas may weaken the ability of G. elata to digest and inhibit Armillaria, thereby destroy the symbiosis balance between G. elata and Armillaria. This research has important scientific value for revealing the symbiosis mechanism of ArmillariaGastrodia elata, and has practical significance for the zoning of G. elata cultivation.