Characterization of pathogenic endogeneous pararetrovirus (EPRV) of Banana streak virus (BSV) in polyploid bananas : Sequencing and molecular mapping. Musa balbisiana strain:Pisang klutuk Wulung

Some 400 million people in developing countries around the world depend on bananas and plantain as staple food. Cultivated bananas are mostly triploid, highly sterile, parthenocapic and originate from two wild diploid species noted A and B for Musa acuminata Colla and M. Balbisana Colla., respectively. Plant breeders need access to as much diversity as possible in order to develop higher yielding varieties with resistance to pests and diseases and other desired traits. Is one of the reasons why the international “challenge program generation” initiative initiates the large scale characterization of the banana germplasm. Unfortunately in the past 10 years, the massive emerging of BSV in banana observed certainly result from the triggering of BSV EPRVs. Nevertheless, the real economic importance at this time is explained not only by the direct effect of the disease on crop yield but by restrictions imposed on the deployment of improved hybrids because the occurrence of BSV EPRVs in many genotypes. Then, within a very short time BSV has become the major constraint for banana breeding programs worldwide. In consequence, all reported banana inter-specific hybrids are considered at risk for a wide and rapid dissemination of BSV; the international Musa germplasm movement for breeding purposes becomes considerably risked. The identification of BSV EPRVs present in banana genome was a first step towards unlocking the breeding programs, the characterization of pathogenic banana BSV EPRVs is required to define adapted molecular markers for a rational use of the genetic resources. EPRV context seems to be widely distributed in a whole range of crops relevant to European and tropical agriculture, including tomato, pepper, potatoes, rice, yam and sugar cane and could therefore threat the performance of numerous breeding programs as well as germplasm conservation.