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Northern corn-leaf blight and southern corn-leaf blight have been found in suscep- 

 tible fields this weekT Only trace amounts are present. These diseases are 

 caused by fungi. Northern corn-leaf blight is characterized by elliptical lesions, 

 that are typically 2 to 4 inches long by a half inch wide. Southern corn- leaf 

 blight is characterized by lesions 1 inch or less in length by a quarter inch wide 

 that have parallel sides. The color of lesions in both diseases is grayish green 

 at first. Later as the tissue dies, they become tan. Northern corn-leaf blight 

 occurs throughout Illinois. Southern corn- leaf blight is usually found in only 

 the southern half of the state. 



Both diseases are effectively controlled by using resistant hybrids. 



Soybeans 



Some soybean fields in southern Illinois have plants infected with bud blight. 

 This virus disease usually appears at the margin of fields, especially when the 

 soybeans are planted next to clover, alfalfa, or pastures. 



Symptoms vary with the stage of development at which plants become infected. In 

 young plants, the terminal bud turns brown and bends sharply downward forming a 

 crook. The buds become dry and brittle. Leaves may be bronzed and the plants 

 remain dwarfed. Plants infected near flowering time are somewhat dwarfed and 

 produce few or no pods, or a few poorly filled pods. Infected plants usually 

 remain green until killed by frost. 



Phytophthora blight is more prevalent this year than it has been for several years. 

 This is probably caused by the large acreage of susceptible soybean varieties 

 planted and by the ideal conditions for infection by the phytophthora fungus. 

 Plants may be killed at any stage of growth. The infected plants usually turn 

 yellow, the leaves wilt and droop, and the plant dies. Usually, brown lesions 

 can be found on the basal part of the stem of the large dead plants. 



SEED TREATMENT OF WHEAT 



The mercury seed treatment fungicides can be used on wheat planted this fall. 

 Seed treatment of wheat is recommended for the control of seedling diseases caused 

 by seed and soil-borne fungi that cause stand reductions, and for the control of 

 stinking smut or bunt. Mercury seed- treatment fungicides will not control loose 

 smut. 



The best results have been obtained with seed that has been custom treated at 

 elevators and at seed and feed houses. Satisfactory results can be obtained with 

 drill box formulations of the mercury seed -treatment fungicides. The use of drill 

 box mixing assures that only the seed that is planted is treated. TREATED SEED 

 IS HIGHLY POISONOUS: IT MUST NOT BE USED FOR FOOD OR FEED. DO NOT PUT TREATED 

 SEED IN GRAIN GOING TO MARKET. 



The new systemic fungicide, Vitavax, used for smut control in small grains, will 

 not be available for use on certified or market wheat seed this year. The Uni- 

 Royal Company has requested label clearance for the use of this fungicide on 

 foundation and registered seed only, and at this date, they have not been granted 

 a label for such use. The company expects a decision from the Food and Drug 

 Administration within a week. We will keep you informed on developments. 



