Figure 4.

Botrytis bud rot development, caused by Botrytis cinerea, in a greenhouse production facility. (A) Early infection on developing inflorescence, showing browning and decay of leaves and bracts. (B, C) Advanced stages of bud rot, where the entire inflorescence has been destroyed. (D) Close-up of diseased harvested inflorescences, showing development of mycelium within the bud and decay. (E) Colony of B. cinerea recovered from diseased tissues showing prolific sporulation on the edge of the colony and sclerotial development in the center. (F, G) Scanning electron micrographs of conidiophores and conidia of B. cinerea from culture. The points of spore attachment to the conidiophore head can be seen. (H, I) Lesions on cannabis leaves resulting from spore deposition of B. cinerea from infected inflorescences to cause individual spots that enlarged into necrotic lesions.