260 EXPERIMENT STATION RECORD. 



of Agriculture relating to a number of functional and unknown disorders of culti- 

 vated plants. 



Report of the botanist, H. L. Bolley (North Dakota Sta. Upt. 1904, pt. 1, i>i>. 

 33-56, ph. 7). — In studying the cause of the wheat blight, which results in the 

 so-called "white heads," or unfilled heads of a white color, the author has been 

 unable to isolate a definite organism causing the disease, but he believes that the 

 trouble is due to a fungus which is transmitted by way of the soil, in a somewhat 

 similar manner to that causing the wilt of flax. The disease seems to be more gen- 

 eral in poorly drained areas and in fields in which wheat has been continuously 

 cropped, and for the present the author recommends draining of the heavy areas and 

 rotation of crops as means for preventing this disease. 



Considerable attention has been given to the cause of "starchy," spotted grains in 

 hard wheats, the trouble being locally known as "white belly." Grains of this 

 character are generally graded as soft wheats, and are believed to be inferior to the 

 hard wheats of the Northwest. A number of experiments were carried on in w T hich 

 germination trials, microscopical tests, and cross-fertilization trials were made, and 

 also the effect studied of exposure of harvested bundles to the ordinary weather 

 conditions. 



From the results the author believes that the white spots are not due to crossing, 

 nor are they matters of heredity, but that this peculiar mottling is due to the action 

 of moisture, air, and sun upon the grain while it is yet in the chaff. If the weather- 

 ing action is long continued, the grains become evenly bleached over their entire 

 surface. The color and hardness of the grain can be maintained by proper care in 

 harvesting and curing. 



Experiments to determine whether an efficient dry process of treating wheat for 

 the prevention of smut could be discovered indicated that while this might be pos- 

 sible the methods tested were not as efficient as the use of formaldehyde, etc., and 

 required quite as much care in their application. The claims for Ozoflet pow T der as 

 a smut preventive were not found to be justified. 



In tests of the effect of evaporation upon solutions of formaldehyde, covering 

 periods of from 1 to 15 days, it was found that the solutions, instead of becoming 

 weaker on standing, became more concentrated. Hence, solutions which have stood 

 open for a number of days may be depended upon as being fully as strong as when 

 first made. Experiments on the effect of different types of water on formaldehyde 

 treatment showed little or no influence. 



Regarding the popular belief that smutted wheat may be safely used for seed after 

 it has been stored for a period of years, tests of the influence of age upon the germi- 

 nation of smut spores showed that they do not lose their vitality under ordinary 

 methods of keeping for a period of at least 7 years. An account is given of investiga- 

 tions on the breeding of wheat for resistance to smut and rust, with a general discus- 

 sion of the effect of rust on the wheat crop. The author suggests that seed may be 

 used from rusted crops providing it is thoroughly screened, and where this practice 

 is carried out the effect of breeding will be secured to some extent. 



Notes are given on the germination of light-weight wheat from a rusted crop, and 

 also germination tests of frosted grains. From a microscopical examination of frosted 

 grains the author states that apparently the injury is confined to the outer bran 

 layer, and that there is no apparent change in the inner layer or contents of the 

 grain. Whether the quality of the grain for producing flour is injured would be deter- 

 mined only by a chemical and manufacturing test, 



For more than 12 years the author has been carrying on experiments on potato 

 seal), and during these studies he has often noticed what appeared to be a tendency 

 to immunity on the part of certain individuals or strains. From 1893 to 1900 some 

 selective work was carried on with the Early Ohio potato, and the results obtained 

 show that it is possible to increase resistance to disease to a considerable extent. 



