DISEASES OF PLANTS. 963 



Investigations concerning the cereal fungus Rhynchosporium graminicola, 

 E. Heixsex [But. Mux., Aht. I'tldiizttiM'hntz, lldinhiin/, S [l!W)-19(Jl) , /iii. l.J, p/s. /,). — 

 For a number of years a disease of cereals due to Rln/nchosponum ijmminicola has 

 been under observation. It was first noticed as occurring upon rye and later upon 

 barley. The disease seems rather widely distributed throughout Germany, and it 

 produces an effect upon the host plant quite similar to that caused by the mildew 

 Erysiphe grdminls. Inoculation experiments show the disease could be rather easily 

 produced upon rye and Imrley, less easily upon wheat, and oats seem to be entirely 

 immune from attacks of the fungus. Frost injuries and the use of certain fertilizers, 

 such as those containing potassium perchlorate, seem to favor the spread of the dis- 

 ease. The different stages of the fungus are described at considerable length and its 

 possible affinities are pointed out. 



A California beet disease, Linhart {Oesterr. JJngar. Ztschr. Xuckerind. ». Landir., 

 1901, p. 26; aba. In Boi. Ccnthl, S7 {1901), No. 10, pp. 356,S57).—ln 1899 there 

 is said to have appeared a sugar-beet disease in California that in some localities 

 destroyed from 10 to 100 per cent of the beets. The cause of the disease was 

 attributed t() bacteria and it was thought probable it was the same disease as that 

 known to oc(.-ur in Germany. Diseased beets preserved in alcohol were examined 

 by the author and the symptoms of disease are described. The beets begin growth 

 in the usual way and the first symptom of disease is shown when they have put out 

 6 or 8 leaves. The root puts out numerous fine roots, often the body and main root 

 having a felted appearapce. The leaves are undeveloped and die, while the crown of 

 " the beet changes color from yellow to brown, and finally becomes l)lack and rotten. 

 The flesh of the beet becomes discolored and with a short exposure to the air turns 

 black. Sometimes the roots are uncolored; at other times they are discolored to the 

 tap root. ]Many specimens appearing normal are found upon examination to be 

 woody internally. The fundamental tissues are poorly developed, the cells being 

 much smaller than in normal beets. Numerous bacteria 1.5 to 2/^ in length with 

 about half that diameter were foimd that resembled those occurring in diseased Ijeets 

 in Europe, but as all available material had been in alcohol for some time no cultures 

 could be made. The author believes the bacteria are saprophytic in the soil and 

 find their way to beets whose growth had been interfered with l)y unfavorable con- 

 ditions. Attention should be given to the proper irrigation and fertilizing of the crop 

 and as an additional precaution seed should be soaked for 20 hours in a 22 per cent 

 solution of copper sulphate before planting. 



Abacterial disease of beans, G. Delacroix {Ann. Inst. Xaf. Agnm., 24 {1897- 

 1900), No. 16, pj). 151-160, figs. 3). — An account is given of a bacterial disease of 

 beans which has been noted in the environs of Paris, a preliminary notice of which 

 has already been given elsewhere (E. S. R., 11, p. 948). 



Orange and lemon rot, C. W. Woodworth {California Sta. Bnl. l.;<), ji/i. .1-11, 

 figs. 5). — During the past year considerable loss has been reported in early shipments 

 of oranges and lemons. The cause of the rot is said to be due to the presence of a 

 mold, PeniciUiuin digitutum. The characteristics and growth of the fungus are 

 described at some length and the method of attack is shown. The rot of these citrus 

 fruits is not usually an orchard disease. In lemons the infection occursalmost entirely 

 in the curing houses, and in oranges after they are packed and usually in transit to the 

 market. Navel oranges, however, often come to the packing house badly infected 

 by the disease. The trouble I)egins at the navel end and may be scarcely visible 

 from without, though connnoniy a slight split or perhai)S a little exudation of guni 

 will indicate the point of entrance of the fimgus. In this case the trouble clearly 

 began in the orchard and sometimes infection has taken jjlace before the fruit is 

 ripe. The conditions for the entrance of the fungus are described. .\ munl)er of 

 preventive measures are suggested, among them the use of refrigerator cars, and 



27718— No. 10—02 a 



