The Fungus Pests of Garden Plants 



germinating zoospore, the germ-tube of which has pierced the cell- 

 wall, and is^growing inside the cell, as shown at + . 



No. 4 



No. 5 affords a view of another piece of tissue of the stem of a 

 Potato plant, and shows the hyphse of Pkytophtkora infestans running 

 in -the cell-walls ; (a) nucleus of a cell ; the other contents shown 

 are crystals and chlorophyll corpuscles. 



No. 6 



No. 6 is a section of a Potato tuber : A, the cell-walls ; B, the 

 starch grains ; C, the mycelial hyphse. 



Spraying Potato plants twice or thrice with the mixture known 

 in France as bouillie bordelaise (Bordeaux stirabout) prolongs the 

 growth of the plant until late in the season, and in some instances, 

 especially in certain districts in the West of Ireland, it has proved 

 effective in warding off the attack of Phytophthora infestans, thereby 

 increasing the weight of the produce. The mixture is made in the 

 proportion of 20 Ib. of sulphate of copper and 10 Ib. of lime to 

 100 gallons of water. 



Those who leave Potatoes to rot in the ground because the crop 



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