Fig. 2
From: Apple Valsa canker: insights into pathogenesis and disease control
Conidial germination of Vm and infection to apple bark tissues. a Conidium (Co) germinates to form germ tubes (Gt) that penetrate the cortex (CTX) through ostioles. b Germ tubes (Gt) invading dead host tissue at an infection site (Is). c Spread of pathogenic hyphae (Hy) in the cortex (CTX) and the production of new invasion site (Is). d Hyphae (Hy) invade the bark tissues and spread in host cells (Hc) and intercellular spaces, causing tissue decay