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.
To minimize issues with this disease, space parsley plants apart and water in the morning. Septoria leaf spot â Septoria leaf spot on tomatoes is also a very common cause of yellowing or yellow to tan to brown lesions with yellow border on parsley leaves.light â Another reason your parsley plant has yellow spots on leaves may be from blight, with onset symptoms that include brownish patches on the foliage. As this infection progresses, typically the blotching overtakes the leaves, causing the plant to die.