A preliminary study of the genetic diversity of Bolivian oca (Oxalis tuberosa Mol.) varieties maintained in situ and ex situ through the utilization of ISSR molecular markers

ISSR molecular markers have been used to investigate genetic diversity of oca (Oxalis tuberosa Mol.), an Andean neglected tuber crop species. Sampling procedure allowed a preliminary study of the genetic diversity at the intra- and intervarietal levels. Twenty tuber lots conserved in situ in the microcentre of Candelaria and ex situ in the Toralapa Centre (Bolivia) were identified. Four ISSR primers amplified a total of 25 fragments of which 17 (68%) were polymorphic. These experiments show that the structure of oca varieties is mainly based upon vernacular names with a greater differentiation among tuber lots than within them, supporting agromorphological data. ISSR technique enlightened the existence of heterogeneous varieties in oca and divergence between in situ and ex situ conservation, strategies. These observations are potentially linked to the different ways of management of tubers in these two conservation systems

Genomic introgression in laboratory evolved hybrid races, Cytorace 1 and Fissioncytorace-1 of Nasuta-albomicans

Nasuta-albomicans complex (NAC) of Drosophila is an artificial hybrid zone comprising of Drosophila nasuta nasuta, Drosophila nasuta albomicans and 16 Cytoraces, which are the evolutionary products of a long range hybridization experiment conducted in the laboratory environment. Occurrence of centric fission in the X3 chromosome of Cytorace 1 led to the derivation of Fissioncytorace-1. Molecular techniques have emerged as powerful and valuable tools for detection and exploitation of genetic polymorphism. In the present study, Cytorace 1 and Fissioncytorace-1 were subjected to Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) analyses to determine the introgression of D. n. nasuta and D. n. albomicans genomes. It was found that Cytorace 1 and Fissioncytorace-1 exhibit similarities in RAPD and ISSR profiles although different combinations of genomic regions could have favoured Fissioncytorace-1, for better morphophenotypes and fitness, when compared to Cytorace 1, which has existed for over 15 years from the time of its evolution in the laboratory environment