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.
Radishes are prone to seed rot or the collapse of seedlings when afflicted with damping off. Donât plant seeds in cold, moist soil and be sure the soil is well-draining. Septoria leaf spot â Septoria leaf spot is a fungal disease that often affects tomatoes but can afflict radishes too. This radish disease is appears as pale yellow, gray spots on foliage that look like water spots. The spots get a gray center and become more circular as the disease progresses.