1906.] ''Black Stripe" of Tomatoes. 



369 



The twigs cut away must not be allowed to lie about on the 

 ground, but must be burnt. 



2. Spraying or sponging the plants with paraffin emulsion, 

 made by boiling together i lb. of soft soap and one gallon of 

 soft water ; remove this from the fire, and while still boiling add 

 two gallons of paraffin. Then churn very thoroughly, till a 

 butter-like mass is produced. The churning should be done 

 with a force pump, as on the thoroughness of the mixing largely 

 depends the efficiency of the material. For sponging down or 

 spraying the bark, add nine times the quantity of water and 

 mix w^ell. For spraying the foliage more water should be added 

 to prevent scorching. It is a good plan to rub the paraffin 

 emulsion with a stiff brush into crevices and ragged bark, where 

 the scales are often found under cover. 



3. A mixture of soft soap and sulphur in hot water has also 

 proved effective. 



A repetition of the paraffin emulsion spray to the bark early 

 in the following spring has been found serviceable. 



The Board have received an inquiry for information as to the 



" Black Stripe" or Black ^ot{Macrospormin tomato) of tomatoes. 



Information regarding this disease will be 

 " Black Stripe " , , . ^ . ^ \ r 01 . t^- 

 of Tomatoes. lound m the Text-Book of Plant Diseases, 



by Mr. George Massee, from which the 



following paragraphs are taken. 



This disease appears to be present wherever the tomato is 



cultivated. The fruit is most frequently attacked, but the fungus 



is also often present on the stem and leaves. The fungus is a 



'wound-parasite, and on the fruit most frequently effects an 



entrance through minute cracks round the style, or at the point 



of insertion of the stem, but may appear on any part of the fruit 



where a puncture of the skin large enough to admit of the 



entrance of the germ-tube of a spore is present. A dark- 



coloured mycelium forms in the tissues, and rapidly destroys the 



cells, consequently the area occupied by the fungus sinks a little 



below the general surface of the healthy part of the fruit. At a 



later stage the sunken surface of a diseased spot becomes covered 



with a delicate, velvety pile of a brownish or blackish-olive colour. 



Microscopic examination shows this pile to consist of closely 



G G 



