A FULL ANALYSIS OF A POTATO CHIMERA

In the variety Arran Victory, which has purple tubers, there was found a tuber half purple and half pink. The pink half produced a plant which had pink tubers with small purple patches. X-ray irradiation of these tubers gave plants which had about five per cent of pink tubers without the purple patches. Breeding and eye-excision experments showed that the pink tubers with small purple patches were periclinal chimeras in which gene P had been lost from L1, L2 plus L3 still having gene P as in normal Arran Victory. The pink tubers without the purple patches had no gene P in L1, L2 and L3. The chimerical pink tubers had purple sprouts, the full pink tubers pink sprouts. The pigmented layer in the tubers of Arran Victory is the phelloderm (secondary cortex), not the primary outer cortex. © 1969 Martinus Nijhoff.