420 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



by transference of " sick" soil, by wind, water, or animals to " healthy " soil ; 

 or by transplanting diseased plants from infected seed-beds. 



Of two varieties of tobacco (« Connecticut Havana ' and * White Burley ') 

 planted side by side in fresh soil, the Burley variety produced a much greater 

 yield, plant for plant, than the Havana variety, but the opposite holds good 

 if the two varieties are planted on soil which has already carried a crop 

 or two of Burley in previous seasons. Efforts have been made to produce 

 resistant varieties, and the paper describes experiments with various types of 

 tobacco. The drooping leaf varieties of Burley are recommended for this 

 purpose. — A. B. 



Tomato Diseases. By C. C. Brittlebank {Jour. Agr. Vict. April 1919, pp. 



231). — Seven, diseases of tomato plants are found in Victoria : — 



Leaf-mould or Target spot {Alternaria solani E. et M.). 



Leaf-spot, Rust or Leaf Blight {Septoria lycopersici Speg.). 



Wilt or Sleepy disease (Fusarium solani (Mart.) Sacc). 



Sclerotium disease (Sderotinia). 



Root-rot {Rhizoctonia solani Kuhn). 



Irish potato blight {Phytophthora infestans De Bary). 



Brown-rot or Wilt {Bacillus solanacearum) . 



Also a new tomato disease, " Spotted Wilt," which has appeared within the 

 last three years, which is carefully described. In the summary it is thought to 

 be identical with one which American plant pathologists have had under 

 investigation as a troublesome disease in winter tomatos. — C. H. h . 



Tomato Diseases in Ohio. By J. G. Humbert {U.S.A. Dep. Agr., Exp. 

 Stn. Ohio, Bull. 321, pp. 159-196; 12 figs.). — The following diseases of the tomato 

 are described : — 



Damping off {Rhizoctonia, Pythium, Fusarium), stems and roots attacked. 

 Fusarium Wilt {Fusarium lycopersici), roots and stems attacked. Bacterial 

 Wilt {Bacillus solanacearum), roots and stems attacked. Stem Rot {Sderotinia 

 Libertiana) , stems near ground are attacked. Leaf Spot {Septoria Lycopersici) , 

 leaves turn yellow. Early Blight {Alternaria Solani), leaves become blotched. 

 Late Blight {Phytophthora infestans), leaves turn black. Anthracnose {Col- 

 letotrichum phomoides), fruit spotted. Rot {Botrytis sp.) (fruit rot). Nematodes 

 {Heterodera radicicola), swollen knots on roots. 



The control measures include soil sterilization, rotation of crops, spraying 

 and ventilation. — A. B. 



Tomato Products. By B. J. Howard and C. Stephenson {U.S.A. Dep. Agr., 

 Bull. 581, pp. 1-24). — The use of unsound material in the manufacture of tomato 

 products is revealed by the number of moulds and other micro-organisms when 

 examined under the microscope. Tomato pulp stored in barrels invariably 

 shows a large number of moulds. This indicates that it is inadvisable to use 

 barrels for storing tomato pulp. — 5. E. W. 



Tomatos, Pollination. By A. G. B. Bouquet {U.S. A . Dep. Agr., Exp. Stn. Oregon, 

 Bull. 158, pp. 1-29 ; 5 figs.). — The yield of tomatos grown under glass is largely in- 

 creased by artificial pollination. The best system is to apply pollen collected 

 on the first and second fingers of the left hand, to the pistils of emasculated 

 flowers. Those flowers are selected for pollination which have fully opened 

 and later closed their petals. The petals and stamens are removed by the 

 thumb and third finger of the left hand, leaving the pistil exposed to receive the 

 pollen. Pollination is carried out every third day when the air of the house is 

 dry. The increased yield of fruit amply repays the cost of extra labour for 

 pollination. — S. E. W. 



Tomatos, S trine Disease of. By S. G. Paine and W. F. Bewlay {Jour. Min. 

 Agr. vol. xxvi. No. 10, Jan. 1920). — The disease known as " Stripe " is very 

 common in tomato nurseries and causes considerable losses, sometimes a total 

 loss in badly infected houses. The symptoms are characteristic and consist 

 of brown stripes on the stems, brown sunken patches on the fruit and 

 brown shrivelled areas on the leaves. It frequently occurs in the seed-bed and 

 necessitates fresh sowings, but commonly does not show itself until the tops are 

 developed. 



The plants arc generally attacked underground, the causal organism being 

 introduced through wounds made by insects, but parts above ground may also 

 be infected through insect bites or infected pruning- knives. 



