Cooking and purifying the base. 3 Next, the gum base is cooked in kettles at 243 degrees Fahrenheit (116 degrees Celsius) until it has melted into a thick syrup. To purify it, workers pass it through screens and place it in a high speed centrifuge before refiltering it, this time through finer screens.
When unusually heavy rains saturate the soil, a tomato plant's leaves may curl. Plant roots need air, just like the above ground parts. When heavy rains saturate the soil, the roots can't get enough air. This can result in root damage, which causes the tomato to react in a similar way to sudden hot weather.
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.