Pathogens Identification and Study on Regularity of Mildew in Cigar Tobacco Leaves from Sichuan

LIU Mengfen; MAI Xuan; LIU Mengmeng; XUE Fang; LI Dong; YE Changwen; ZHU Beibei; XU Pengfei; CHEN Guokang; HUANG Kuo

doi:10.15933/j.cnki.1004-3268.2025.08.011

Abstract：In order to clarify the mildew species that cause mildew during the storage of cigar tobacco stacks and their mildew-causing pattern,the molds were systematically identified by means of selective medium screening,combined with morphology,MALDI-TOF MS identification and molecular biology,and the mildew-causing rules of molds under different environmental temperature and humidity conditions were studied.The results showed as follows,the molds causing mildew in Sichuan cigar tobacco were Aspergillus montevidensis,Aspergillus cristatus and Syncephalastrum monosporum.Aspergillus montevidensis and Aspergillus cristatus grew faster on Salt Czapek Dox Agar,the number of germinable spores in spore suspension decreased with the increase of treatment temperature,heat treatment at temperatures above 50℃for 10 minutes could significantly reduce the number of germinable spores,and high temperature would kill their spores.The growth rate of Syncephalastrum monosporum was faster on Sabouraud Dextrose Agar,and the number of germinable spores was less affected by temperature.The Aspergillus montevidensis grew most favorably at a temperature of 20℃and a humidity of 60%,while Aspergillus cristatus preferred 28℃and 70%.Temperature and humidity had no significant effect on the growth of Syncephalastrum monosporum.It was found that Aspergillus montevidensis had the strongest mildew causing ability under the condition of 60%or 70%humidity and 20℃.Aspergillus cristatus had the highest mildew causing ability at 28℃and 90%humidity.Syncephalastrum monosporum had the highest mildew causing ability at 28℃and 70%humidity.In conclusion,the growth and propagation of major molds can be inhibited by reasonable control of storage temperature and other environmental conditions during tobacco stacking storage,thus reducing the possibility of tobacco mildew.