Figure 1.

Arabidopsis—fungus interaction. (a) Necrotrophic interaction—Sclerotinia sclerotiorum infects Arabidopsis by killing host tissues in advance of hyphal colonization. Trypan blue stains necrotic dead tissues. (b) Hemibiotrophic interaction—Colletotrichum higginsianum initiates infection process by a biotrophic phase at 3–4 days post-inoculation (dpi), which is associated with infection vesicles (iv) and large primary hyphae (ph). Thin secondary hyphae (sh) appear in the necrotrophic phase at 5 dpi. (c) Biotrophic interaction—Erysiphe cichoracearum colonizes the plant surface by producing haustorium (ha) into epidermal cells for nutrient uptake and keeps the host cell in survival till the pathogen completes its life cycle by conidiation.