Comparative assessment of variation in the USA Arachis pintoi (Krap. and Greg.) germplasm collection using RAPD profiling and tissue culture regeneration ability

Arachis pintoi accessions were used to study genetic diversity using RAPD markers. Concurrently, two tissue culture protocols were evaluated for organogenesis and the capacity to generate somaclonal variation. Data were collected on callus growth, callus weight gain, and number of regenerated plants. Robust RAPD profiles were obtained and eight primers amplified 100 different bands with 98% polymorphisms. The proportion of polymorphic RAPD loci was 89%. Average genetic distance was 0.36 and indicated that a large amount of genetic diversity exists within the germplasm evaluated. Genetic distances were used to prepare a dendogram for the A. pintoi accessions that separated them into four groups. A large degree of variability for callus induction and callus weight gain was observed among the accessions. Shoot regeneration was achieved for several accessions on both media with no structures indicative of somatic embryogenesis detected. Root induction was difficult to obtain, and many shoots died during this process. RAPD band profiles of regenerated tissue culture plants were similar to their parent plants, and therefore no somaclonal variation was evident using these methods.