346 EXPERIMENT STATION RECORD. '[Vol.40 



caused by these two species of smut are described, and It is thought that the 

 dwarfing of the host by T. tritici probably contributes materially to the smut 

 problem in the Palouse region of Washington and Idaho. Varietal resistance 

 is believed to be a factor of considerable importance in respect to these 

 diseases, some varieties being affected as much as 50 per cent. Attention is 

 called to these two smuts in order that observations may be made which may 

 confirm the authors' conclusions and also furnish more accurate data regarding 

 their present distribution. 



Resistance of Manitoba wheat to fungus diseases (Compt. Rend. Acad. Ayr. 

 France, 4 (1918), No. 17, pp. 530-584). — This includes information bearing upon 

 the practically complete resistance to smut of the wheat variety Manitoba. 



Comparative smut resistance of Washington wheats, E. F. Gaim.s {dour. 

 Amcr. Soc. Apron., 10 (1918), Xo. 5, pp. 21S-222). — Observations on the com- 

 parative resistance to stinking smut of 13 varieties and strains of winter 

 wheat, made at the Washington Experiment station during 1915, 191G, aud 

 1017, inclusive, showed marked differences between varieties, the reduction In 

 yield ranging From 1.8 per cenl Cor Turkey to 92.16 per cent for Hybrid 128 

 under conditions of maximum Infection. The extreme differences noted are 

 thought to point to two distinct factors whieli tend to control the resistance of 

 wheat to smut, namely, the prevention of Infection as indicated by the marked 

 variations In the percentage of Infected plants among the varieties studied 

 and the prevention «>r smut-ball formation after Infection, as evidenced by wide 

 differences in yield of wheat produced by Infected plants of the different 

 varieties. 



A possible new fungicide for wheat and barley smut, W. W. Mackjk 

 [Science, ». ser., V : {1918), Vo. /.'J7. vp. v ~>i- r >. $16). — Formaldehyde, which is 



very effective for the treatment of seed wheat for stinking smut where Boll 



Infection does uot occur, is said to i>e Ineffective in the Pacific Ooasl sta- 

 in this region, copper sulphate is more widely used, and this, by adhering to 

 the seed, usually prevents si>n infection of the crop. As Btrong solutions of 

 copper sulphate tend to lower the germination of the seed, the expedient of 

 dipping the treated seed in lime solutions has been widely adopted, but this 

 involves a double dipping and a considerable increase in the cost of the 

 treatment. 



In attempting to devise some other method of treatment, the author tested 

 lime-sulphur dip, and the preliminary results with wheat and barley showed 

 that rather dilute solutions of lime-sulphur are very effective against both 

 the stinking smut of wheat and the covered smut of barley. A solution as strong 

 as l part lime-sulphur to l part water had no apparent deleterious effect on 

 the germination of seed wheat and barley. 



The Alternaria leaf spot of cotton. R. C. Faulwettkk [Phytopatlioiogy, 8 

 (1918), No. 3, pp. 98-105, figs. S). — A report is given of a disease of cotton 

 leaves said to be common in South Carolina and believed to be present in other 

 cotton-growing States. 



The lesions of the disease arise in and spread from earlier injuries in the 

 leaf in the majority of instances. The spot is characterized at first by a pale 

 green color, later becoming straw yellow and finally rusty brown, at which 

 stage it has a brittle, papery texture and irregular, concentric zonations. The 

 Alternaria spots are usually found growing from and finally surrounding spots 

 caused by Bacterium malvaoearum and also injuries caused by the red spider. 

 but they are also present where no previous Injury can be detected. The 

 fungus causing the disease has not been definitely determined, but it is con- 

 sidered very similar to 1. ttiiuis. Artificial inoculations haw shown the fungus 



