50 EXPERIMENT STATION EECOED. [VoL 37 



tubers when used for seed. The disease Is not strictly localized at or near 

 the heel end of the tuber, as forn)erly supposed. The fungus grows well as a 

 saprophyte. The disease is reproduced on infecting sound plants with pure 

 cultxires. It is considered advisable to remove this disease from the category 

 of those usually designated by such terms as leaf roll and curl, since the Ver- 

 ticilliura disease is regarded as a specific type of those in which the mycelium 

 affects the wood ve.ssels and for which the term hadromycosis is suggested. 



The disease does not appear to be very common or destructive in the British 

 Isles at present. Preventive measures include rotation and use of seed known 

 to be free from infection. 



Potato spraying experiments for the control of early blight (Alternaria 

 Bolani), R. W. Jack {Rhodesia Agr. Jour., 10 (1913), No. 6, pp. 852-862, pi. 

 1). — A preliminary account is given of the methods and results of spraying 

 tests for control of early blight, the only leaf disease of potatoes prevalent in 

 this territory at the time of the report. 



The author states that the disease may be treated profitably with a 

 4^ : H : 50 Bordeaux mixture, if commenced when the plants are from 4 to 6 

 in. high (but not when the disease has become apparent on the leaves), three 

 or four sprayings giving good results, but seven weekly sprayings being prefer- 

 able. Not less than 75 gal. per acre should be employed. Knapsack pumps with 

 copper tanks have been found suitable to local conditions. An arsenical may 

 be added for Insists if desired. 



Does it pay to spray potatoes in southern RhodesiaP R. W. Jack (Rhodesia 

 Agr. Jour., IS (1916), No. S, pp. 554-S60, ph. 2). — In a progre.ss report of work 

 continued for three years following that above noted. It Is stated that Alter- 

 naria solani, while not usually severe on early crops grown on Irrigated ground, 

 causes losses sometimes amounting to 50 per cent on ground depending on 

 rainfall alone if not properly sprayed. The work herein reported, which dealt 

 with the fairly resistant variety Up-to-Date, Is said to show that the employ- 

 ment of a 4 : 4 : 40 Bordeaux mixture, begun early and repeated weekly. Is 

 profitable to growers in localities where the disease is prevalent. 



Weather injury to rice in 1915 in Italy, B. Marcabelli (Gior. Risicolt., 5 

 (1915), No. IS, pp. 212-216, fig. 1; abs. i« Internal. Inst. Agr. [Rome], Mo. Bui. 

 Agr. Intel, and Plant Diseases, 6 (1915), No. 9, p. 125S). — A period of cool. 

 moist weather from May 27 to June 4, 1915, was associated with an unusually 

 severe chlorosis, soiuetimes death of the foliage, of rice plants and weakness 

 of tlio stalk, these conditions being only In part relieved by the return of more 

 favorable weather. Puceinia oryzce, though found on the foliage In numerous 

 cases, was regarded as only secondary in Its attack, which was supposedly In- 

 duced by the condition of lowered vitality in the rice plants. 



Fusarium blight, or wilt disease, of the soy bean, R. O. Cbomwktx (!7. S. 

 Dept. Agr., Jour. Agr. Research, 8 (1917), No. 11. pp. 421-440. pi. 1, fig. 1).— 

 In a contribution from the North Carolina Experiment Station, the author 

 describes a disease of soy beans due to F. tracheiphilum and gives the results 

 of Investigations to determine the parasitism of this species of Fusarium and 

 the relationship of the species on the soy bean to that causing a wilt disease of 

 cowpeas. 



The disease on the soy bean Is characterized by a chlorosis and shedding of 

 the leaves or leaflets, followed by the death of the plants. It has been observed 

 In several localities In North Carolina on soils lnfecte<l with cowpea wUt. Cul- 

 tural and morphological studies, as well as reciprocal Inoculation experiments, 

 have shown that the two diseases are caused by the same species of Fusarium. 

 Infection Is thought to occur through the roots, but the presence of nematodes 

 does not appear to increase the percentage of blight. The character of the soil 



