NOTES AND ABSTRACTS. 



163 



Tobacco Wildfire. By F. A. Wolf and A. C. Foster {Jour. Agr. Res. xii. 

 pp. 449-458 ; Feb. 191 8 ; plates). — A disease of tobacco causing death of leaves 

 is described, its origin being the attack of the bacillus Bacterium tabacum. A large 

 amount of damage has been reported although the disease seems a comparatively 

 new one. — F. J. C. 



Tomato, &c, A Disease of, caused by a Nsw Species of Phytophthora. By 



G. H. Pethybridge and H. A. Lafferty (Sci. Proc. Roy. Dublin Soc. xv. pp. 487- 

 505, Feb. 1919 ; plates). — The root system and lower part of stem are caused 

 to rot, leading ultimately to the death of the plant. The authors propose " foot- 

 rot " as the name of the disease. A species of Phytophthora, for which the name P. 

 cryptogea is proposed, has been isolated and proved to be the cause of the disease. 

 The same type of disease associated with the same fungus has been found in 

 Petunia, and something very similar, if not identical, in Aster and Cheiranthus. 

 The disease is contracted from the soil, and may be prevented by thorough heat- 

 sterilizing of the soil [and pots]. The tops of diseased plants may be rooted 

 and will grow away to fruit healthily. — F. J. C. 



Tomato- growing. By C. W. Waid (U.S.A. Exp. Stn., Michigan, Bull. 89.' 

 9 figs.). — The usual cultural directions are given. Caterpillars are destructive. 

 They can be poisoned with a mixture of Paris green, molasses and bran. 



Cracking of the fruit is due to sudden changes in the supply of water in the 

 soil. Dry or blossom end rot is due to the same cause. Leaf-spot (Septoria), 

 Leaf Mould (Cladosporium) and Downy Mildew (Phytopthora) can be controlled 

 by spraying with Bordeaux mixture. When tomatos are repeatedly grown 

 on the same soil they are liable to suffer from Fusarium Wilt and Rhizoctonia . 



S. E. W. 



Tomato Seeds, Utilization of. By F. Rabak {U.S.A. Dep. Agr., Bull. 632). — 

 The waste material in pulping tomatos is dried and the seeds separated from 

 the skins by a separator. Oil is extracted from the seeds by pressure or by 

 extraction with carbon tetrachloride. The former process yields the purer 

 product, but the latter gives the larger yield. The refined oil is pale yellow 

 and has a nutty taste and smell. It may be used as an edible oil or for making 

 soap. The meal from the extracted seed is mixed with the skins and used for 

 feeding cattle. — S. E. W. 



Vanda luzonica Loher. By R. A. Rolfe (Bot. Mag. t. 8709 ; May 1917). — 

 A native of the Philippine Islands. A plant for the tropical house. Flowers 

 showy, over two inches wide, sepals and petals white, with a tinge of purple to- 

 wards the apex, lip three-lobed, pouched at the base. — L. C. E. 



Vegetables, Supposed Deterioration of. By C. F. Kinman and T. B. 

 McClelland (U.S.A. Exp. Stn., Porto Rico, Bull. 20). — The generally accepted 

 view that vegetables from temperate zones deteriorate when grown through 

 several generations in the tropics, is proved by prolonged series of experiments 

 to be incorrect. The yield and character of vegetables is greatly influenced 

 by the season of planting. Seed rapidly deteriorates in the tropics, when exposed 

 to the humid atmosphere. This accounts for many of the bad results. 



The difficulty may be overcome by preserving the seed in bags, which are 

 placed in air-tight vessels, at the bottom of which calcium chloride is placed. 

 A disc of wire gauze is placed between the calcium chloride and the seed bags. 



5. E. W. 



Vegetation and Reproduction with Special Reference to the Tomato. By 



E. J. Kraus and H. R. Kraybill (U.S.A. Exp. Stn., Bull. 149, Jan. 1918 ; figs.).— 

 The authors discuss the causes of flower, and leaf-shoot production, giving the 

 results of experiments and observations, and conclude : Plants grown with 

 abundance of available nitrogen and ample opportunity for assimilation are 

 vigorously vegetative, but unfruitful. Plants grown at first with much, then 

 with a moderate, supply of available nitrogen are less vegetative, but fruitful. 

 Those grown at first with abundance of nitrogen, then with a very low supply, 

 are neither vigorous nor fruitful. The conditions for the initiation of floral 

 primordia, and probably also blooming, are not necessarily those accompanying 

 fruit-setting ; nor is the failure of the latter entirely due to lack of pollination or 

 fertilization. Markedly vegetative plants may shed their flowers entirely, and 

 markedly non-vegetative retain them many days without development. The 

 conditions conducive to fruitfulness are largely due to a proper balance between 

 carbohydrate and nitrogen constituents of the plant ; and pruning promotes 

 or retards fruitfulness by affecting this balance. More exact information is 

 required before an accurate estimate of the causes of unfruitfulness and sterility 

 can be made. — F. J. C. 



