202 



INJURIOUS INSKCTS AND FUNGI. 



[Dec, 1894. 



wheats and their milling qualities be held two years hence at 

 Melbourne, and that such Conference be composed of wheat 

 growers, millers, and scientific men having a knowledge of 

 wheat and its diseases." 



The Conference further affirmed the desirability of experiments 

 of many kinds in the next two years, and as there are several 

 experts engaged in, and devoted to, this work, including Dr. Cobb 

 and Mr, I'arrer, of New South Wales, and Mr. McAlpine, of 

 Victoria, it is hoped that important results may be obtained. 



It is no small matter to have established the fact enunciated 

 at the last Conference, that there are several varieties of wheat 

 pioved capable of resisting rust to an eminent degree. There 

 can be little doubt that other varieties will be found resistant 

 or made resistant by careful selection as advised by Dr. Cobb. 



BOUILLIE BORDELAISE AND POTATO DISEASE. 



In the Zeitschrift fur PflanzenkrankJieiten, Dr. Paul Sorauer 

 reports the results of an interesting experiment with bouillie 

 bordelaise as a remedy for potato disease, which was carried out 

 in the dry season of 1893. 



The experiment was made in a season in which the disease 

 failed to make an appearance, and there was scarcely any pro- 

 longation of the period of vegetation of the haulms dressed 

 with sulphate of copper. In the late varieties the foliage of the 

 dressed plants remained green only a day longer than that of 

 the untreated plants, and in the case of an early variety (Early 

 Rose), the cessation of vegetation in the treated plot was simul- 

 taneous with that on the undressed plot. There was also very 

 little difference in the yields. On a plot of Daberschen potatoes 

 the yield of the undressed section was equal to that of the 

 treated section, and on another plot sown with a variety known 

 as Euphyllos, the undressed plants furnished a larger yield than 

 the dressed. But, on the whole, the average yield from the 

 plants which had been treated with the bouillie was 2 per cent, 

 in excess of the produce of the undressed plots, and even this 

 small increase sufficed to cover the cost of the treatment. Dr. 

 Sorauer remarks that, in other experiments, it has also been 

 found that the copper treatment somewhat retards the develop- 

 ment of the potato plants, and this result corresponds with the 

 results recorded above, and with those of most other similar 

 experiments. This retarding influence, however, is only observed 

 in the period before the outbreak of the disease in early varieties, 

 the haulms of which had not fully developed their foliage. The 

 yields obtained before the appearance of the disease were larger 

 on the undressed plots ; but this result was changed in favour of 

 the treatment m soon as the disease had made its appearance. 



