17 



be directed towards prevention rather than cure. The following 

 methods will serve to check the disease : 



1. The use of rotation by which other crops are grown on in- 

 fected soil for a number of years. 



2. Control of insect pests as these serve to spread the disease. 



3. In the case of cauliflowers and white turnips, destined for 

 immediate consumption, early harvesting of the crop is recommended, 

 as the disease is worse when the plants are a])proaching maturity. 



4. In cases where the turnips are stored they should be placed in 

 a well-ventilated and dry cellar in which the temperature can be con- 

 trolled. The minimum temperature for growth of the germ is about 

 45^ ; hence if the cellar can be cooled to this temperature no rot Avill 

 take place. 



5. The planting of immune varieties. There are a number of 

 varieties which do not seem subject to the rot, thus the Jersey Navet 

 is almost immune and, ander flel4. conditions, the following varieties 

 show less than 5 per cent, of rot : Greystone Improved, Purple Top 

 Mammoth, Early American Purple Top, White Egg, White Lily, Red 

 Top. 



SOFT ROT OF SWEDE OR YELLOW TURNIPS. 



This disease of Swedes has been observed in the Province for a 

 number of years. In the year 1896, considerable damage was done to 

 the turnip crop before the time of harvesting by soft rot. In many 

 cases the turnips which had been culled out as unfit for storage were 

 left out in the field and were ploughed down in future cultivation, and 

 thus the soil was infected. The turnip crop of 1902 was also infected 

 with rot. Many farmers estimated their loss that season at about 

 one-third of the entire rrop. The disease was particularly bad in the 

 London district. 



Cause. This rot is .so caused by a microbe which has a similar 

 action on the plant to the organism already described as being the 

 cause of the soft rot of white turnips. 



Symptoms. Growing Swedes affected with the rot are usually 

 distinguished from the sound turnips by the appearance of the leaves. 

 At first the lower leaves bc^^me flabby and have a dull green color 

 which gradually changes to a yellow shade as the leaves dry. The 

 lower leaves appear to be the first aflfected, and the growth continues 

 in the upper or middle leaves as the lower ones drop ofl", thus produc- 

 ing what is commonly called " necky turnips." The plant by this 



