Cultivated species are susceptible to fungal infections including downy and powdery mildew. Lilac bushes can be prone to powdery mildew disease. It is susceptible to powdery mildew. It has extremely soft powdery clean white sand. Sesame Oil is a mixture effective against powdery mildew. Lacosamide is a powdery, white to light yellow crystalline compound. It is a powdery, granular, light brownish to white substance. The grapes ripen early but can be prone to powdery mildew. It has good resistance to powdery mildew. Other fungal diseases are black knot, "Alternaria" spot and fruit rot, and powdery mildew. Viognier can be a difficult grape to grow because it is prone to powdery mildew. "Sawadaea tulasnei" is a fungus that causes powdery mildew on tree leaves. Milk has proven effective in treating powdery mildew of summer squash, pumpkins, grapes, and roses. Cross pollination has resulted in some varieties developing resistance to powdery mildew. Later in development, powdery mildew causes discoloured, small seeds.