Population of castor species as source of creation initial material of different ripeness groups

It is showed that a wide range of variability in node quantity on main (to central cluster) - from 5 to 16 and more nodes - is observed in populations of castor species. It is note that plants with 4-5 nodes are ultra-precocious and plants with 16-17 nodes are late-ripening. This clear morphological marker should be used for selection of plants of different ripeness groups and be included in breeding process of castor species with different vegetation period. A scale is suggested for selection and evaluation of varieties and families on various ripeness groups as well as for classification of breeding material of castor by this marker.