AP.STUACTS OF PUBLICATIONS OF Till*: AGIIICULTIIRAL EXPERIMENT STATIONS 

 IN THE I'NITEI) STATES. 



Alabama College station, Bulletin No. 21 (New Series), December, 1890 (pp. 16). 



A NKW KOOT-ROT DISEASE OF COTTON, G. F. ATKINSON, PH. B. 



(pp. .)-ll, illustrated). — Notes on observations by the author on a root 

 rot of cotton occuring in Alabama, which was caused b^^ the root gall 

 nematode {Iletcrodcra radicicola, Miill.). The article is illustrated with 

 a plate made from a photograph of specimens of the diseased roots of 

 cotton. 



The external manifestations of the disease in cotton are strikingly similar to 

 tliose of tbe root-rot diwaso caused by Ozonium auricomum as described by Paniniel 

 [8oe Texas Station Bulletin No. 7, oj- Experiment Station Record Vol. I, p. :>18J, tbe 

 irregular distribution of tbe spots as well as tbe tendency to increase in extent, and 

 t-oniclinies tbe cbanging of tbe spots. Also as iii tbe case o[ Ozonii(m, the firstexterual 

 sign of tbe disease is tbe sudden wilting of a plant on a hot, sunshiny daj', espec- 

 ially a(fcr rain. This similarity in external ai)pearance is easily accounted for from 

 tbe nature of the disease, since the condition of the roots prevents the absori)tion of 

 water in quantities equal to that transpired by tbe leaves, though there be an abun- 

 dance of water in the soil. From this time tbe plant rapidly declines. 



Tbe disc^afed plants begin to die about the time of " chopping out" the cotton in 

 May, when the plants are quite small, and the disease continues throughout tbe 

 season . 



An account of the nematode worm is given, together with sugges- 

 tious as to remedies, which are largely taken from the author's article 

 on nematode root-galls in Bulletin No. (new series) of the station 

 (See l^Lxpcriment Station Record Vol. I, p. 1S5). The importance of 

 keeping the soil free from the nematodes by taking care not to plant 

 infected roots or tubers is strongly urged, especially in view of the 

 lact that no sure remedy for the worms is known after the land is once 

 infected with them. Itotation of crops and clean cultivation are the 

 chief means advised for reducing the numbers of these worms. 



Beport ofthe Alabama weather service for November, 1890, 

 P. n. Mell, Ph. D., and J. M. Quarles (pp. 12-15). — Notes on the 

 weather and a tabnhited monthly summary of meteorological observa- 

 tions and of soil temperatures at dei)ths of from 1 to 90 inches. 



547 



