Prevention is better than cure and its also applicable when it comes to dealing with most plant diseases. Many diseases cannot be effectively controlled once symptoms develop or become severe. Various diseases related to plantation crops have been extensively discussed in this book. Wheat may suffer from the attack of insects at the root; from blight, which primarily affects the leaf or straw, and ultimately deprives the grain of sufficient nourishment; from mildew on the ear; and from gum of different shades, which lodges on the chaff or cups in which the grain is deposited.