Brown Rot Disease Caused by Trichoderma hamatum on the Edible Lily, Lilium leichtlinii var. maximowiczii

Lilium leichtlinii var. maximowiczii is commonly known as the edible lily or sweet lily. Bulbs of this edible lily are frequently used in traditional Chinese medicine, and they are revered for their nutritional content. As of 2018, brown rot disease on cultivated L. leichtlinii var. maximowiczii bulbs has become a disease of concern in Jilin Province, China, with a disease incidence of 29.43%. The bulbs infected with brown rot disease appear as large, regularly shaped, and yellow-brown or black-brown lesions. However, the causal agent is not yet known. Therefore, this study aims to confi rm both the causal pathogen by using Koch’s postulates and to further establish, to the species level, the identity of this organism via morphological and molecular methods. The pathogen was later identifi ed as Trichoderma hamatum. Healthy bulbs were inoculated with T. hamatum, which produced the initial disease symptoms with brown spots appearing at the inoculation sites; the same pathogen was then isolated again from diseased bulbs. To the best of our knowledge, this is the fi rst report of bulb rot disease of cultivated L. leichtlinii var. maximowiczii caused by T. hamatum in China. Our work may be benefi cial, especially for designing control measures for bulb rot disease in the commercial cultivation of L. leichtlinii var. maximowiczii.