THE POTATO 369 



of corrosive sublimate (bichloride of mercury) in thirty gallons 

 of water. Place the potatoes in a gunny sack and suspend in the 

 solution for two hours. Then empty them out on the floor or in 

 the sun to dry before planting. Various methods are used for 

 treatment, but the above is satisfactory and possibly as easily 

 done as any. 



397. Dry Rot (Fusarium oxysporium) is widespread over the 

 potato regions of this country and Europe. It is a fungous dis- 

 ease which attacks the base of the plant, penetrating into the 

 roots and tubers and causing the final wilting and early maturity 

 of the plant. It causes a further development of dry rot in 

 storage. There is a tip burn and yellowing of the leaves, to- 

 gether with a rolling up of the foliage. Affected tubers can be 

 determined by cutting off the stem end slightly and observing a 

 browned ring near the skin and occasionally a browning going 

 entirely through the tuber. Spraying will not control the disease, 

 but care in selecting disease-free seed and planting on soils which 

 have not become inoculated with the disease will be the proper 

 precautions to keep it under control. 



