16 MASS. EXPERIMENT STATION BULLETIN 292 



vapors as far as possible. The pure chemical is highly inflammable and explosive 

 and for this reason the men should be cautioned against smokingcr lighting matches 

 when using it. 



SUMMARY 



In greenhouses, soil treatments with carbon disulfide emulsion have given good 

 control of the root-knot nematode and have restored normal yields. A stock 

 emulsion containing 68 per cent carbon disulfide, 26 per cent water, and 6 per cent 

 rosin fish oil soap was diluted in water to make a 1-50 concentration and applied 

 to the soil at the rate of 1 gallon per square foot. 



The cost for chemical materials is approximately nine-tenths of a cent per 

 square foot. 



Where soil inhabiting fungous pathogenes are also present, the addition of 2/3 

 gallon of formaldehyde to the above formula is recommended. 



Removal of the infested roots when the houses are cleaned out, decay of root 

 material remaining, and thoroughness of application contribute much to the 

 effectiveness of carbon disulfide emulsion in controlling the root-knot neniatode. 

 A delay of at least 2 to 3 weeks after the old crop is cleaned out before treatment, 

 during which interval the beds are kept moist and warm, assists in the decay of 

 the old roots. A further delay of one week after treatment is necessary before 

 planting. 



Exposure to carbon disulfide for more than five hours at one time maj- cause 

 illness and this is an objection to its use. Suggestions are offered for avoiding this 

 danger. 



LITERATURE CITED 



L Chapman, P. J., and Parker, N. M. Carbon disulfide emulsion for the control 

 of nematode. Science 70:18, 1929. 



2. Doran, \V. L. Acetic acid as a soil disinfectant. Jour. Agr. Research 



36:269-280, 1928. 



3. C.leisberg, J. Wirkung und Rentabilitat der Bodenentseuchung mit 



Schwefelkohlenstoffsapikatgemisch. Obst- u. Gemiisebau 76:33, 1930. 



4. Godfrey, G.H. The depth distribution of the root-knot nematode, Heterodera 



radicicola, in Florida soils. Jour. Agr. Research 29:93-98, 1924. 



5. Jones, L. H. The effect of environment on the neniatode of the tomato gall. 



Jour. Agr. Research 44:275-285, 1932. 



6. Newhall, A. G. Control of root-knot nematode in greenhouses. Ohio Agr. 



Expt.Sta.Bul.451, 1930. 



7. Schaffnit, E., and Weber, H. X'ersuche zur Bekampfung des Wurzelalchens, 



"Heterodera radicicola." Obst- u. Gemiisebau 75:77-78, 1929. 



8. Watson, J. R. Root-knot. Fla. Agr. Expt. Sta. Ann. Rept. 1928:47, 1929. 

 9 Root-knot investigations. Fla. Agr. Expt. Sta. Ann. Rept. 1929:54, 



1930. 



Publication of this Docu.ment Approved by Commission on Administration and 

 Finance. 



FIANCE. y 

 3M-l-'33. Nd, 7307 



