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.
There are two primary fungus diseases that can produce black spots on tomato plant leaves: Septoria leaf spot and Alternaria leaf spot, also known as early blight. Septoria and Alternaria differ slightly in appearance and prefer slightly different weather climates.
Stem has gone brown halfway up. Q. My tomatoes are grown in a greenhouse along with pepper plants. The stems have gone completely brown about half way up the stem, with a brown patch about 2 inches long. Some leaves have gone brown as well. Some of the tomatoes went brown. I have picked them off.