760 EXPERIMENT STATION RECORD. 



The hypothesis seems warranted, from the facts known, that the first 

 rust spots do not either directly or indirectly owe their origin to a more 

 or less close proximity to barberry, but to a pathological condition of 

 the grass plant itself, a condition which may have originated from an 

 in lection of the young plant in the spring by the winter spores of the 

 rust, or from a disease germ carried in the plant from one year to 

 another.— f. W. woll. 



Investigations on the specialization of the grain rusts, J. Eriks- 

 son (Ztschr. Pflanzenlcranlc., 7 (1897), Wo. 4, pp. 198-202).— The author 

 continues his observations on the grain rusts. In this paper an account 

 is given of numerous inoculation experiments. In the first series 10 

 species of grass, representing G genera— Lamarkia, Triticum, Hordeum, 

 Secale, Dactylis, andPoa — were inoculated with Puccinia graminis from 

 barberry in 1896; and the results of these experiments are reviewed. 

 In every case definite results were secured showing the susceptibility 

 of these species to barberry rust. 



Iu the second series of experiments the inoculation material was 

 taken from the plants previously inoculated from the barberry. It 

 appears that the forms developed on wheat successfully inoculated 

 barley and wheat, but failed on oats and rye. The form grown on 

 Lamarkia aurea inoculated that grass and oats. A second form from 

 wheat gave some evidence of successful transfer to barley, but failed 

 on oats, rye, and wheat. The form developed on Triticum desertorum 

 failed on wheat and oats, but was successful on the host species, barley, 

 and rye. A third form originated on wheat was very successful in 

 inoculating wheat, but less so when applied to barley, rye, and oats. 

 Spores from Trisetum disticJiophyllum inoculated oats, but failed on 

 wheat and rye. A form from barley infected rye and oats, but pro- 

 duced no rust on wheat or barley. Spores from Poa ccesia produced 

 rust abundantly when transferred to that species of grass. 



The information relative to the experiments is tabulated and shows 

 the origin of the inoculation material, inoculated plants, number of 

 infections, and time within which rust pustules developed, etc. The 

 time between the inoculation and appearance of rust pustules varied 

 from 10 to 52 days. 



Eighth annual report of the station, M. Hollrung (Jahresber. Vers. 

 Stat. Ifematodenvertil. u. Pflanzenschutz, Halle, 8 (1896); abs. in Centbl. 

 Bait, u. Par., 2. Abt., 3(1897), No. 19-20, pp. 535-538).— The report gives 

 an account of the principal fungus and insect enemies of the sugar 

 beet, potato, chicory, garden plants, cereals, legumes, fruits, and forest 

 trees, and the means adopted for combating them. 



It is stated that the potato rot due to Phytoplitliora infestans was 

 especially severe on crops grown on heavy soils, while those grown on 

 light sandy soils were almost exempt from injury. Experiments with 

 Bordeaux mixture on the diseased plants are said not to have given 

 entirely satisfactory results. The presence of organisms in the soil 



