Fungus diseases of sugar beet
There is no doubt that intensified culture of the sugar beet has made it much susceptible to the attacks of animal and vegetable parasites. In Europe parasitic diseases of the sugar beet are much more numerous than in this country. Several have long been known to cause serious injury to sugar beet culture.
European growers have long been accustomed to ascribe certain diseased conditions to soil exhaustion. The term “beet sickness” has been given to a large number of poorly defined diseases. Practical growers believe that want of potash or phosphates causes this condition. From the very exhaustive researches of Liebscher and Kuehn it appears that none of the chemical elements have been found wanting, nor has the addition of manure or fertilizers restored the conditions essential for the growth of the sugar beet. It has also been observed that a soil capable of producing a good crop was rendered "beet sick” by the introduction of root parasites. Among the parasites which cause the soil to become “beet sick” certain eel worms (Heterodera schachtii) and root-rot fungi should be mentioned. Kuehn has shown that when these enemies are removed from the soil beet culture again is possible. These diseases cause a destruction of the beet itself, but there are other enemies that indirectly lessen the yield, among these Spot Disease of the Beet (Cercospora beticola), Beet Rust (Uromyces beta), White Rust of Beels (Cystopus bltii) and Downy Mildew of the Beet (Peronospora schachtii) are the principal fungi which affect the leaves. Two of these diseases have only been recorded for America: Spot disease and beet rust. To bring together the matter of fungus diseases I give here a short account of the fungus enemies of the sugar beet in America.