Onion White Rot

Onion white rot Common name Onion white rot Causal agent It is a fungal disease caused by a fungus in the genus stromatinia. Scientific name Stromatinia cepivora Symptoms & Signs The leaves turn yellow, wilt, and eventually fall off, especially in dry conditions. The roots and bulbs also show white, fuzzy fungal growth covered with small black sclerotia. Mature, older leaves are more prone to show signs of infection. Transmission Unlike most fungi, this one does not produce spores. Instead, it stays in the soil as sclerotia and produces fungal growth that attacks the roots. The sclerotia can spread to other healthy plants through infected tools, water, or wind. Cool, moist weather conditions favor the growth of this disease. Time of concern Midsummer to early fall Common hosts Onion Garlic Leeks Shallots