Demonstration of Fungicides for the Control of Neck Rot in Stored Onions (2011) - 3 pages
Botrytis neck rot is a common problem in stored onions in Saskatchewan. Sweet and white onions are most susceptible to neck rot, followed by the reds, with the yellow storage types showing the greatest resistance to the disease. There is no genetic resistance to botrytis neck rot, but for reasons of growth habit cultivars do show differing degrees of sensitivity to neck rot. The initial inoculum for neck rot arises from infected crop residues left in the soil or from cull piles. During cool, moist weather these disease sources produce air-borne spores which blow onto the foliage of onion crops developing in adjacent fields. If field conditions are suitable some species of botrytis (ie; B. squamosa) may produce lesions on the onion leaves but in dry environments like Saskatchewan the resulting damage to the foliage is rarely sufficient to jeopardize yields. The real damage is done when the fungus invades the bulb via the wound created when the onion top is removed at harvest.