Late symptoms of Sclerotinia sclerotiorum in Brassica napus

In the late stage of the disease, the stem pith is hollowed out, the cortex is longitudinally cracked, and after vascular infection, oily brown spots are produced, which lose luster and appear pale yellow, grow hyphae and form sclerotia when wet. The infection on the pod was waterlogged light brown at first, then turned to white spot, wet rot in the humid climate, white hyphae on the pod, and sclerotia formed inside and outside the pod. After the seed infection, the surface is rough, gray and dull, and some of the diseased seeds are wrapped by white hyphae, forming small sclerotia.