PN-5866 



Figure 8. — Typical clusters of tubers from the collection in Guadeloupe, 

 showing differences in tuber shape, size, and number, and length of 

 stolons. 



riod of about 2 months. After that, seeds will germinate uniformly 

 in about 30 days. The viability can be preserved for about 1 year 

 by dry, cool storage. 



Open-pollinated seedlings have been produced in abundance, 

 especially in Guadaloupe. These have been the chief materials used 

 for the selection of new varieties. 



The seedlings produce successively two to six stems, each of 

 increased size. These stems form a rosette at first, until a climbing 

 stem develops. A few seedlings remain for a prolonged period in the 

 rosette stage. Meanwhile, the primary nodal complex forms and 

 becomes the source of fibrous roots and stolons. 



Seedlings grow rapidly to a normal size within the first year 

 and exhibit from the beginning some of the physiological and 

 morphological traits that clones derived from them will show. Be- 

 cause of high variability in growth rates and earliness, selections 

 can be made at an early stage. Some seedlings do not bear tubers, 

 and yield variations in tuber-bearing seedlings are obvious even at 

 the first harvest. Seedlings can also be selected reliably for tuber 

 type and color. 



Plants also vary in stolon production, length of stolons, pro- 

 portion of stolons that tuberize, time of initiation of tuberizations. 



11 



