448 EXPERIMENT STATION RECORD. [Vol.43 



secured from diseased tomato fruits in West Virginia ; tbe second from diseased 

 potatoes in West Virginia ; tiie third from diseased potatoes in Maine. 

 Tliirty tomato plants were used in each experiment, and it was found 

 that plants inoculated with tlie strain of the organism from tomatoes 

 showed pronounced willing of tlie younger growtlis and several stem 

 lesions, while the plants inoculated with the strains isolated from potatoes 

 showed no evidence of wilting or of stem lesions but did have numerous spots 

 on the lower leaves. The differences are said to have become more marked 

 daily until all plants inoculated from the tomato were dead, while tliose inocu- j 

 lated from the strains of the potato grew nicely and shed their lower leaves 

 so that no evidence of infection remained. 



Cultures isolated from the potato when inoculated upon tomato produced 

 leaf spots, but did not produce the scalded, wilted appearance that is always 

 considered characteristic of the late blight, while the cultures isolated from the 

 tomato produced typica.1 late blight symptoms on the tomato. 



" Crinkle " on Xorthwestern Greening, R. H. Roberts {Phy to pathology, 

 9 (1919), No. 6, pp. 261-263, pis. 2). — An account is gi,ven of an unusual injury 

 on Northwestern Greening apples in Wisconsin in 1918. The trouble is con- 

 sidered apparently the same as the physiological crinkle reported by McAlpine 

 (E. S. R., 31, p. 244). Limited observations are believed to indicate that the 

 cause of this disease is comparable to that of the injury mentioned by Brooks 

 and Fisher (E. S. R., 36. p. 50). It was not determined when the browning 

 or injury began, but it was presumed to be associated with the extreme 

 drought conditions which prevailed during the season. 



Reversion in black currants {Gard. Chron., 3. set:, 66 (1919), No. 1115, 

 p. 233).— This work of Lees has already been noted (E. S. R., 42, p. 150). 



Diseases of orange and other citrus plants, J. R. Johnston and S. C. 

 Bruneb (Estac. Expt. Agron. Cuba Bol. 38 (1918), pp. 7-54, pis. i5).— This 

 body of information regarding the character, causation, results, and control 

 of diseases affecting citrus plants in Cuba is intended to bring this general 

 subject so far as possible up to the date of its publication. 



Forest botany [and pathology], R. S. Hole (Rpt. Forest Research Inst. 

 [Dchra Dun], 1917-18, pp. 2-4). — Studies continued during the year regarding 

 the amount of oxygen and carbon dioxid present in badly aerated soils and the 

 relation of these gases to inferior root development in sal (Shorea robusta) 

 gave reason to believe that the trouble is correlated with a deficiency of oxygen 

 and an accumulation of carbon dioxid, possibly also of other substances. 

 Absence of reproduction by sal in certain forests appears to be due chiefly 

 to denudation and drying of the soil. 



The gradual weakening of ulla grass (Anthistiria gigantea) observed in 

 areas protected fi'oni fire is believed to be due to an accumulation of dead 

 leaves and culms and the consequent suppression of the young shoots. A 

 system of annual cropping prevents this trouble. 



Spike disease of sandal was studied in the field. Experiments were inaugu- 

 rated to test the effects of px'olonged action of such factors as deficiency of an 

 essential nutrient substance, acid soil, deficiency of water, interference with 

 translocation of organic food, and fungi, and in general the relation between 

 such factors (when acting continuously or rapidly) and the occurrence of 

 starch in the parts above ground. 



Black canker of chestnut, L. Petri (.Ann. R. 1st. Super. Forestale Naz. 

 Firenze, S (1917-18), pp. 151-185, pi. 1, figs. S). — This is a morphological and 

 biological study of the black canker of chestnut and of its association with 

 fungi, notably Blepharospora cambivora and Coryneum pemiciosum. The 



