The volume of flame, however, is increased by inert gas, and there is a proportionate diminution of the heating effect. Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3 Various. Nitrogen by itself is an inert gas, colorless and uninflammable. Scientific American Supplement No. 819 Various.
Tomato Spotted Wilt Virus. The tomato spotted wilt virus (TSWV) causes dark brown, purple or black spots on leaves. The spots can spread to the stems, causing cankers and streaks. The foliage begins to wilt once the disease spreads, and the leaves become stiff.
Do not can tomatoes with late blight. Tomatoes showing signs of late blight disease have firm, dark brown lesions that quickly become large, wrinkled and somewhat sunken. Diseases such as this may lower the acidity of the tomato flesh to a level that makes it unsafe for canning.ate blight in both tomatoes and potatoes is caused by the oomycete Phytophthora infestans, and is a worldwide destructive disease. Under favorable weather conditions, tomato and potato crops can be destroyed within days.