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.
Defeating Tomato Disease. Q. I have 4'x 8' raised beds in my garden. My peppers, squash, and beans grow well, but my tomatoes have a horrible disease. The leaves get spotty, turn yellow, and eventually fall off. The fruits do fine, but the vines look horrible. Through the help of garden books, I think it's Verticillium Wilt, Fusarium Wilt, or Septoria Leaf Spot.