874 EXPERIMENT STATION RECORD? 



in which inoculations were made of various species and races of grass with 

 Erysiphe graniinis. 



The leaves were injured and thereby rendered susceptible to the attacks of 

 conidia and ascospores. The injuries were inflicted by bruising the leaves, 

 pressing them under weights, the action of narcotics, heat, etc.. and it is pointed 

 out that injuries similar to these artificially produced in the experiments are 

 constantly inflicted on plants in nature by animals, frost, wind. hail. etc. In the 

 experiments with barley leaves they were rendered susceptible by the agricul- 

 tural practice of rolling the crop. 



As an explanation of the susceptibility of injured leaves, the author assumes 

 that in consequence of the vitality of the leaf cells being affected the pro- 

 tection normally afforded by enzyms or similar substances ceases. 



The results obtained in these experiments show that "susceptibility can be 

 induced not only by various kinds of mechanical injury, but also by such inter- 

 ference with the normal functions of the cell as follows the application of anes- 

 thetics and heat. The conidia of the Grst generation produced on leaves of a 

 strange host plant previously subjected to the action of* alcohol, ether, or heat 

 retain the power of infecting their original host, and do not acquire the power 

 of infecting normal leaves of their temporary host.*' 



The vegetative life of some Uredineae, J. Ertkssox (Ann. lint., 19 (1005), 

 No. 73, i>i>. 55-59; aos. in Bot. Cental., 98 (1905), No. Vi. p. ',15).— The author 

 presents in a paper read before the British Association some additional evidence 

 to substantiate his mycoplasm theory regarding rust infection. 



Report of the botanist and geologist, W. Lochhead (Ann. Rpt. Ontario 

 Agr. Col. <m<l Expt. Farm. .>'/ (1905), i>}>. %3-58, figs. 2). — A review is given of 

 the progress in this department during the author's occupancy as professor of 

 botany and geology, after which an account is given of some spraying experi- 

 ments with grapes for the protection of the vines against grape rot and experi- 

 ments for the destruction of the San Jose scale. 



The season was unsatisfactory for spraying experiments, as there was but 

 little disease present in any of the vineyards, and the experiments will be re- 

 peated. In the spraying experiments for the protection against the San Jose 

 scale a number of mixtures were tested, but none of them proved as effective as 

 the lime-sulphur washes in common use. A brief account is given of potato 

 spraying in which Bordeaux mixture and Paris green were compared with a 

 number of other combined insecticides and fungicides, and the best results were 

 obtained where the Paris green-Bordeaux mixture was applied. 



Notes are given on a number of fungus diseases which have been given some 

 attention during the past season, and the report concludes with a discussion of 

 the injurious action of Bordeaux mixture in apple orchards. An instance of 

 possible injury to the foliage and fruit is cited, and experiment station and other 

 literature is ([noted to show the possibility of injury from the improper use of 

 Bordeaux mixture, bid the author concludes from his observations that it is prob- 

 able that the leaf spot was caused by the scorching of the leaves by the hot sun 

 shining through the moistened surfaces of the leaves. He does not consider it 

 demonstrated that the injury was due f ( > the spraying with Bordeaux mixture. 



Treatment of grain for smut, ('. A. Zavitz (Ann. Rpt. Ontario Agr. To/, and 

 Expt. Farm. 31{ 1905), }>i>. 182-185) . — The results of treating 2 varieties of oats 

 and 2 of winter wheat with solutions of formalin, copper sulphate, potassium 

 sulphid, etc., for the prevention of smut are described. It is shown that from 

 the untreated seed an average of about per cent of the smut occurred in the 

 case of winter wheat and 4 per cent in the case of oats, while the crop produced 

 from the seed which had been treated with formalin was entirely free from 



