PN-5222 



Figure 8. — Rooted stem cutting of D. rotundata. 



Only healthy plants should be selected as sources of planting 

 material. 



The crown or head piece of large tubers is also excellent 

 planting material. Tips of the tubers (tails) and midsections are 

 also good planting materials, but because they lack preformed 

 buds, are slower to sprout than are head pieces and whole tubers. 



Tubers to be cut for planting should be selected at harvest. 

 Such tubers should be large, true to type, and free of insect dam- 

 age. They should be stored at cool temperatures, protected from 

 the sun, and inspected periodically. Tubers are normally cut to 

 size (100 to 500 grams) and allowed to dry 1 or 2 days before 

 planting. Small pieces yield proportionately greater tubers per 

 unit of weight than do large pieces, but large tuber pieces are 

 usually planted to obtain large individual tubers. Wood ashes have 



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