146 EXPERLMENT STATION. [Jan. 



A SPINACH DISEASE NEW TO IVIASSACHU- 



SETTS. 



BY HARRY M. JENNISON, B.S. 



Earlv in the spring of 1010 the writer's attention was at- 

 tracted to a plot of winter spinach growing on the college, 

 grounds Avhich had been practically mined by a fungus causing 

 a Slotting of the leaves. The olivaceous color of the spots on 

 the diseased leaves suggested the possible presence of a Clad- 

 osporiuni as the causal organism, but upon microscopical exam- 

 ination the fungus was determined to be Heterosporiuni varia- 

 Ue, Cke. This organism is closely related to that causing the 

 lleterosporium disease of cultivated carnations, known as 

 " fairy ring." 



It was su]iposed that a disease which could so comjdetely 

 devastate this crop would have been extensively reported, but 

 ujjon thorough search of the literature only a few references to 

 this particular spotting of spinach could be found. In 1905 

 Clinton ^ reports having collected in the open market in New 

 Haven. Conn., specimens of spinach leaves affected with the 

 above-mentioned fungus, and he refers to it as " leaf mold." 

 IIalst(Ml - in his investigations on ihe fungi attacking the 

 si)inach pbint does not include Ifrfcrospnrlin)! in his list. Since 

 1!)0S lieed ^ has been studying its occurrence and injurious 

 effects in the truck crop regions of N^irginia, where it causes 

 hirgc losses nnniially to the truck farmers of that State. At 

 Amherst the disease was found infecting winter spinach, grow- 

 ing on two widely separated ])lots. Immediately adjacent to 

 one of these was a considerable area set with young spinach 



• Clinton, O. P., Connecticut Agriciiltural Experiment Station, report for 1905, Part V., p. 275. 

 2 Halstead, B. D., New .leraey Aa:riciiUural Experiment Station BiiUetiti No. 70, 1890. 

 ' Reed, H. S., in Virginia Agricultural Experiment Station circular No. 7, revised edition, 

 p. 80, 1910. 



