44 FIRST REPORT ON ECONOMIC BIOLOGY. 



It is important that the lime should be freshly burnt lime, and the 

 sulphate of copper of at least 98 per cent, purity. In the following- 

 winter, just before the bursting- of the buds, spray ag-ain with 2 Ibs. 

 of sulphate of copper, | Ib. soft soap, and 50 gallons of water. 



SLEEPY DISEASE OF TOMATOES. 



Fusarium lycopersici (Sacc.). 



This is undoubtedly the worst disease tomato growers have to 

 contend with at the present moment, and unfortunately it is spreading 

 and making- its appearance in new areas. 



A very large number of inquiries have been received respecting it 

 during the past year, and scores of diseased plants. 



Experiments have been made with seedlings from affected soil, 

 by transplanting- them to soil dressed with strong- solutions of copper 

 sulphate, and in other cases to soil dressed with sulphur. The latter 

 have given better results, but in neither case were the plants saved. 



Frequent watering with a weak solution of copper sulphate was 

 also tried, and up to a certain stage g-ave great promise, but on the 

 plants reaching a height of about eighteen inches, they suddenly 

 collapsed, and quickly died. 



The disease is due to a soil fungus, which enters the plants by 

 the roots. The first signs of attack are noticeable by the leaves droop- 

 ing- and changing- colour; later the stem collapses, and ultimately 

 becomes covered with a delicate white mould, which produces spindle- 

 shaped spores in large numbers. If allowed to remain in the ground, 

 irregular yellowish patches appear on the decaying stem. If a trans- 

 verse section be made of the lower portion of the stem a brownish 

 ring is noticeable just below the epidermis. 



So far as is known plants that are once attacked always die. 

 Spraying is useless. 



Soil in which the disease has appeared should be treated with 

 ground unslaked lime, which should be thoroughly incorporated with 

 the soil. After a week it should be watered, and then allowed to lie 

 for a time before planting anything in it. 



When grown under glass, every part of the house should be well 

 washed with a carbolic acid solution, consisting of one part of acid 

 to twenty parts of water. 



All affected plants should be removed and burnt upon the first 

 appearance of the disease. 



