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AGRICULTURAL AND MISCELLANEOUS NOTES. 



Root-Knot Disease in Cucumbers and Tomatoes. 



Cucumbers and tomatoes are often affected by a disease 

 induced by the Root-knot Eel worm [Keterodera radicicola). 



The first symptom of attack is a drooping and yellowing of 

 the foliage, followed by the stem becoming limp and a collapse 

 of the entire plant. 



The finer branches of the root are more or less studded with 

 swollen portions or " knots," varying in size up to one quarter 

 of an inch across; knots of larger size are also often present 

 on the thicker branches of the root (see illustration). 



Microscopic examination shows the presence of numerous 

 eelworms in the knots. 



The eelworms escape from the knots into the soil, where 

 they remain for a time and then enter the roots of other 

 plants. 



There is no method known by which eelworms in the roots of 

 plants, or in the soil in which plants are growing, can be 

 destroyed without injuring the plants. 



To destroy eelworms present in soil, it must be thoroughly 

 saturated three times, at intervals of a fortnight, with the follow- 

 ing solution : — Carbolic acid one part to twenty parts of water. 



A second remedy is mixing the soil intimately with gas- 

 lime. 



In either instance the soil so treated must remain for at least 

 six weeks before it can be used. 



When soil in a house is infected, it is safest to remove the 

 whole and treat it outside ; the interior of the house should 

 then be thoroughly washed with carbolic acid one part, water 

 eight parts.* 



* Copies of this article maybe obtained in leaflet form free of charge and post free 

 on application to the Secretary, Board of Agriculture, 4, Whitehall Place, London, 

 S.W. Letters of application so addressed need not be stamped, 



