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.
What causes tomato plant leaves to turn yellow? Yellow leaves that have purple, distorted veins are a sign that psyllids have infested the tomato plant. Treatment involves looking on the bottom of leaves for insects, removing them and applying a pesticide to the growing area. Tomato plants that stop growing and turn yellow all over may have the curly top virus. The beet leafhopper transmits this disease by jumping from plant to plant.