f>12 SUMMARY OF CURRENT RESEARCHES RELATING TO 



J. B. Rorer * directs attention to the diseases of Cassava (Manihot sp. ) 



in Trinidad. The question lias become important there as the cultiva- 

 tion of the plant has very much increased of late years. He finds the 

 leaf-diseases it is liable to are caused by several species of Gercospora 

 causing leaf-spots, and by Glocosporium Manihotis, which attacks the 

 petiole : the latter fungus also attacks the stem. On the roots there has 

 been recorded a disease of little-known fungoid origin in Jamaica, and 

 in the East a bacterial disease bas been diagnosed. 



A root-rot of tomato has been traced by Clara 0. Jamieson f to the 

 fungus Piioma destructiva. The fungus forms spots on the leaves of 

 tomatoes and potatoes, and is an active wound parasite on ripe tomatoes. 

 A long series of inoculation experiments were made and the vitality of 

 tbe Phoma was found to be. considerable ; no more advanced fruiting 

 stage was discovered. 



J. W. Roberts % has investigated the wintering of Glomerella cingulata, 

 tbe fungus that causes bitter-rot of apple in America. He found that 

 tbe fungus lived during the winter in mummified fruits, and also in 

 cankers produced by the fungus, and there serve as a source of infection 

 in the succeeding year. The cutting out of cankers and all dead parts 

 of the trees should be carried out as far as possible. 



James R. Weir § has identified Rhizina inflata as the fungus causing 

 tbe death of pine seedlings. The white mycelium with whicb their roots 

 were covered was believed at first to be that of Armillaria mettea, as it 

 bad penetrated the cortical and bast tissues whicb were choked with 

 resin. Later in the season tbe fruiting bodies of Rhizina appeared, and 

 inoculation experiments proved that it was tbe source of the mischief. 



M. Savelli |] bas investigated the fungus Glwosporium musarum witb 

 reference to the barm it causes to bananas exported to Europe from the 

 Canaries. He describes the appearance of the fungus on the fruit ; it 

 causes splitting of the skin and rotting of the tissues. Cultures were 

 made and tbe behaviour of the fungus in artificial conditions is de- 

 scribed. It does not attack leaves in the open unless as a wound 

 parasite. 



J. Franklin Collins IT records tbe finding of chestnut bark disease on 

 the fruits of the tree. The fungus Endothia parasitica forms elongate 

 blisters on the nuts. In one case they were found on nuts still within 

 the burrs. The writer warns the public as to the danger of disseminat- 

 ing the disease with nuts which are to all appearance healthy. 



Y. Oemun and P. J. Anderson ** describe the ravages in America of 



* Bull. Dept. Agric. Trinidad and Tobago, xvi. No. 2 (1915) pp. 36-68. See also 

 Bull. Agric. Intell. Rome, vi. (1915) pp. 996-7. 



f Journ. Agric. Research, Washington, iv. No. 1 (1915) pp. 1-20 (8 pis.). See 

 also Bull. Agric. Intell. Rome, vi. (1915) pp. 998-9. 



\ Journ. Agric. Research, Washington, iv. No. 1 (1915) pp. 59-64 (1 pi.). See 

 also Bull. Agric. Intell. Rome, vi. (1915) pp. 999-1000. 



§ Journ. Agric. Research, Washington, iv. No. 1 (1915) pp. 91-5 (1 pi.). See 

 also Bull. Agric. Intell. Rome, vi. (1915) p. 1001. 



|| Ann. R. Accad. Agric. Torino, lvii, 1914 (Turin, 1915) pp. 184-92 (1 pi.). See 

 also Bull. Agric. Intell. Rome, vi. (1915) pp 883-4. 



f Phytopath., v. (1915) pp. 233-5 (1 rig.). 

 ** Phytopath., v. (1915) pp. 260-5 (4 figs.). 



