152 EXPEEIMENT STATIOISr EECOKD. 



For proper spraying the fungicide should be applied under sufficient pressure 

 to thoroughly vaporize the solution. In order better to cover the grapes, the 

 removal of some of the leaves on the vine is recommended. 



Comparative tests of difEerent fungicides for the control of the downy 

 mildew of grapes, J. Mahoux (Rev. Yit., 41 (1914), No. lOJfO, pp. 91-94).— The 

 author reports upon the comparative value of a dozen fungicides for the con- 

 trol of the downy mildew of grapes, comparisons being made with ordinary 

 Burgundy mixture. 



The season of 1913 is said to have been a very favorable one for the de- 

 velopment of the fungus. The best results were obtained with Burgundy 

 mixture, to which were added casein, saponin, and gelatin to increase the 

 spreading power of the mixture, copper acetate solution, and an iron-copper 

 sulphate solution. Ordinary Burgundy mixture gave nearly as good results, 

 but the others tested were not favorable in their action, especially if used in 

 more dilute strengths than advocated by their manufacturers. When sprayed 

 upon the upper side of the foliage, as is most commonly done, none of the 

 mixtures showed any superiority over ordinary Burgundy mixture if the amount 

 of copper in them was less than that in the Burgundy mixture. Where the 

 more adhesive fungicides are used, the author recommends that they should 

 be applied from below and in such quantities as are necessary to cover the 

 leaves and grapes. He claims there is no economy in attempting to lower the 

 cost by reducing the amount of fungicide used in seasons that are favorable for 

 the growth of the fungus. 



Notes on diseases of citraceous plants, E. Jarvis (Queensland Agr. Jour., 

 n. scr., 1 (1914), A'o. 4, pp. 268-271). — As the result of recent investigations the 

 author has found a number of diseases of citrus trees, and he describes a collar 

 rot due to Fusarium limonis, a root rot caused by Arniillaria sp., and a gumming 

 disease, the cause of which is not definitely stated. In connection with these 

 disease preventive measures are suggested for their control. 



Some notes on the scab of grapefruit, G. L. Fawcett (Porto Rico Prog., 

 6 (1914), No. 22, pp. 6, 7). — A brief description is given of the scab of grape- 

 fruit. This the author says may be controlled by sprayiug with Bordeaux 

 mixture, but as the use of the fungicide would tend to destroy beneficial fungi 

 which hold in check scale insects, it is not thought advisable to spray except as 

 a last resort, in which case an insecticide should follow the use of a fungicide. 

 Control measures involve the removal of any growth that is infected, and he 

 states that fungi occurring on cover crops, such as pigeon peas and the sword 

 bean, will produce scabs resembling the true citrus scab. As yet no definite 

 connection between these diseases has been determined. 



The author states that his attention has recently been called to the claims 

 that DipJodia natalensis causes considerable decay on fruit shipped from Porto 

 Rico, but that he has been unable to discover it in typically affected specimens. 

 The fruits were, however, infected with the well-known withertip fungus (Col- 

 Jetotrichum gloeosporioides ) . 



[A fungus disease of coffee] (Planters' Chron., 9 (1914), No. 3, pp. 32, 33).— 

 An injurious disease of coffee trees is described as noted in the Province of 

 Coorg, British India. It is said to occur in patches on the collar of the trees 

 with little or no tendency to spread, but all the trees affected are usually killed, 

 as are young healthy trees planted in their places, the fungus remaining active 

 in the soil. It is thought the organism may be Irpex flavm. Remedial meas- 

 ures recommended include burning all affected wood, heavy liming of the soil, 

 use of Bordeaux mixture painted on the stems, and the free admission of light 

 and air to the affected parts. 



