IDENTIFYING PECAN CULTIVARS BY ISOZYMES AND INHERITANCE OF LEUCINE AMINOPEPTIDASE

More than 170 pecan [Carya illinoensis (Wangenh.) K. Koch] cultivars w ere evaluated for malate dehydrogenase, phosphoglucose isomerase, phos phoglucomutase, leucine aminopeptidase (LAP), and diaphorase (DIA). Is ozymes of LAP were observed in two regions after starch gel electropho resis. The faster region of activity (Lap-1) was polymorphic and consi stently expressed in leaves, wood, and roots. Controlled crosses sugge st that Lap-1 is simply inherited and controlled by at least two allel es. DIA was well resolved and scorable only from leaf material and pro duced a complex banding pattern. The ability to differentiate among cu ltivars by isozymes was good. The 177 cultivars sorted into 72 classes . Forty of the cultivars (23%) possessed a unique series of isozyme pa tterns. Most cultivars (124 of 177) shared common banding patterns wit h less than four other cultivars. From the inheritance models of four isozymes, some historical pedigrees can be questioned. Most notably, ' Western Schley' could not have been parented by 'San Saba' based on th e inheritance of Mdh-1 and Lap-1.