54 EXPERIMENT STATION RECORD. 



author reaches the conclusion that there is no evidence to support the theory 

 that an epidemic of late blight can originate fi'om the planting of infected 

 seed tubers. 



An explanation of " sereh " of sugar cane, H. H. Zeijlstba (Ber. Dent. 

 Bot. GeselL, 29 (1011), No. 6, pp. 330-333).— It is claimed that sugar cane is 

 of hybrid origin, varying in its susceptibility to the attack of the " sereh " 

 disease, which is an infectious disease the cause of which is as yet unknoAvn. 



The susceptibility of wlieat to bunt (Tilletia) in relation to the time of 

 sowing', O. MuNEEATi (Atti R. Accad. Lincei, Rend. CI. Soi. Fis., Mat. e Nat., 

 5. scr., 20 {1911), I, No. 11, pp. 835-840). — The results of experiments on the 

 susceptibility of wheat to stinking smut are given. 



It was found that independent of certain other factors which are more or less 

 favorable to the propagation of Tilletia on wheat, the temperature at the time 

 of sowing and during the first stages of germination exercises a decisive in- 

 fluence on the receptivity of the wheat to the smut. A very early sowing of the 

 fall wheats and a very late sowing of the spring wheats generally gave healthy 

 plants. Late autumn or early spring sowings, accompanied by low temperatures 

 and by the normal humidity during the first developmental stages of the plants, 

 produced the greatest amount of bunt infection. 



A spot disease of cauliflower, Lucia McCulloch ( U. 8. Dcpt. Agr., Bur. 

 Plant Indus. Bui. 225, pp. 15, pis. 8). — A description is given of a spot disease 

 of cauliflower which was first called to the attention of the Department in 

 1909. 



The leaves of the diseased plants were closely covered with brownish to 

 purplish-gray spots 1 to 3 mm. in diameter. There were also larger diseased 

 areas due to the coalescing of the spots. From these spots the bacterium was 

 isolated and successful inoculation experiments made on the leaves of cabbage 

 and cauliflower. 



The organism is believed to be an undescribed form, and the name Bac- 

 terium maculicolum n. sp. is given it. A description is given of its morphology, 

 cultural characters, and temperature and other relations. 



Inoculation experiments seemed to indicate that it affects the leaves of 

 cauliflower and cabbage, but the heads of cauliflower gave no satisfactory 

 results when inoculated with the organism. The temperature relations are 

 such that inoculations made during July, 1909, proved unsuccessful on account 

 of the high external temperature. The organism is able to grow at tempera- 

 tures below freezing, but it fails to grow at a temperature of 85° F. Usually 

 the leaves attacked bj' the disease fall from the plant. 



The effect of club root disease upon the ash constituent of the cabbage root, 

 H. S. Reed (Abs. in Science, n. ser., 3-J (1911), No. 868, p. 218).— There was 

 found in the roots of cabbage plants diseased by club root an appreciable 

 increase in the amounts of calcium, magnesium, potassium, and phosphoric 

 and sulpliuric acids. The greatest increase was found in the potassium and 

 appeared to be coupled with an increase of protoplasmic substance and an 

 accumulation of starch. The proportion of calcium to magnesium and of 

 potassium to sodium was greater in the diseased roots than in healthy ones. 



Fusarium disease of cucumbers and other plants, G. E. Stone {Massachn- 

 setts Sta. Rpt. 1910, lit. 2, pp. 62-65). — The occurence of Fusarium diseases 

 on a considerable number of plants is mentioned, after which a brief descrip- 

 tion is given of this fungus on cucumbers and other plants. In cucumber 

 houses the disease has become serious within the past year, and in addition 

 to cucumbers a summer crop of muskmelons was practically destroyed. 



An opportunity has not been given for a thorough study of remedies, but as 

 cucumber and other crops are generally severely forced, it is thought that mis- 



