DISEASES OF PLANTS. 641 



Infection experiments were carried on with a number of local rust-proof 

 wheats, but none of them showed immunity to the rust P. triticina, and only 

 one toward F. graminis. As a result of his studies the author thinks that rust- 

 proof and rust-rosistaiit are terms that should be used with great caution. 



Diseases and pests of cereals. H. I've (Jour. Dciit. A(/r. Victoria, 7 (1909), 

 Xo. 0. y>/>. 3lS8-.n\i). — The results of ohser* ations are given on the occurrence 

 of wheat smuts, and experiments on the production of snnit-resistant varieties 

 of cereals are desirlbed. Comparative tests have been carried on w.itli varie- 

 ties of wheat in regard to their resistance to the stinking smut, and decided 

 differences are noted in their susceptibility to the fungus attack. A durum 

 variety, Medeah, has proved almost entirely free from this disease. Some other 

 varieties proved resistant to a consideraole extent, although not entirely 

 immune. 



In the report of the experiments the relative values of ditferent treatments 

 for the prevention of smut and effect of fungicides on germination ai-e given. 

 Soaking the seed in corrosive sublimate solution or a strong solution of copper 

 sulphate proved the best treatment for the prevention of the smut, while the 

 tests to determine the effect of these fungicides on germination were so variable 

 as to be inconclusive. The results of breeding experiments with different varie- 

 ties of wheat to produce smut resistance are briefly described. 



The mildews of cereals, G. M. Kekd (Bui. Torrey Bot. Club, 36 (WO'J), 

 Xo. 7, pp. So3-.iHS). — In a previous paper (E. S. R., 21. p. oO). the author has 

 given a suunuary of the work that has been done on the physiological speciali- 

 zation of the Erysipliaceie. In the present paper an account is given of investi- 

 gations with the mildews of barley, rye. wheat, and oats that supplement those 

 previously described ( E. S. K.. 18. p. 244). 



In the experiments the author has obtained all (»f the iivailable si)ecies and 

 fornis of Triticum, Secale. Hordeuni. and Aveua, and cross inoculations have 

 been made with conidia. So far as tested all species of Avena are susceptible 

 to the oat mildew. All varieties of Tritiruiii nihjarc are likewise suscei)tiblc to 

 the wheat mildew. There were, however, certain varieties of 7'. (licoccuiit which 

 were liractically immune to the wheat mildew, while other vai-ieties of this 

 same species were quite snsce|)tible. Some si)ecies of Hordeum were found 

 immune to the barley mildew, and the same seems to be true of certain sjjecies 

 of Secale with reference to rye mildew. It appeal's that under ntunial condi- 

 tions there are well-detlned forms of l-UiiHiplic (jnnninis occurring on the different 

 species of each of the 4 cereals enumerated above. Some interesting facts were 

 brought out relating to the susceptibility of a hybrid between tlie rye and wheat, 

 this hybrid proving resistant to both tlie rye and wheat mildew. 



A brief bibliography of litei-ature r(>lating to this sul)ject is given. 



Experiments relating to rust and smut resistance, I). McAlpink (Jour. 

 Dcpt. Agr. Victoria, 7 (l!)0!)). Xo. .'/, pp. 2')'>-2()0, figs. 2). — Preliminary experi- 

 ments have been conducted in testing varieties for rust resistance .and for 

 liability to stinking smut, and witJi the flag smut of wheat. In connection with 

 the rust, the investigations involved both I'uccinia triticina and also /'. graininis, 

 the latter being by far the more destructive. 



In testing for smut resistance the author sought to confirm tlie claims made 

 that the varieties Florence and (ienoa are i)racticaiiy snnil proof, and that as 

 a consecpience the seeds do not recpiire treatment with fungicides for the pre- 

 vention of smut. In the e.xperiments reported seed was dusted witli spores of 

 stinking smut prior to sowing. The results obtained upon tabulation showed 

 that Florence may have as much as 12 per cent and (Jenoa <>2 |u>r cent of stink- 

 ing smut, although on a whole they are fairly resistant. This seems to dispose 

 of the claim of hereditary resistance on the itart of these varieties. The author 



