[dam-ping-awf, -of] 
| a disease of seedlings, occurring either before or immediately after emerging from the soil, characterized by rotting of the stem at soil level and eventual collapse of the plant, caused by any of several soil fungi. |
damping-off
disease of plant seedlings, caused by such seed- and soil-borne fungi as Rhizoctonia solani, Aphanomyces cochlioides, and species of Pythium, Phytophthora, Botrytis, Fusarium, Cylindrocladium, Diplodia, Phoma, and Alternaria. There are two types of damping-off: preemergence, in which sprouting seeds decay in soil and young seedlings rot before emergence; and postemergence, in which newly emerged seedlings suddenly wilt, collapse, and die from a soft rot at the soil line. Woody seedlings wilt and wither but remain upright; root decay often follows. Greatest losses occur in cold, wet soils in which germination and emergence are slow, often in indoor conditions
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