A REVIEW OF PRSV-P RESISTANCE GENES IN VASCONCELLEA SPECIES AND THEIR APPLICATION TO PRSV-P RESISTANCE IN CARICA PAPAYA
Papaya is one of the major tropical fruit crops worldwide, however it suffers from several debilitating diseases and pests. Papaya ring spot virus type P (PRSV-P) is a severe, widespread disease of Carica papaya and is transmitted by numerous species of aphid, including Myzus persicae and Aphis gossypii, in a non-persistent manner. Development of PRSV-P resistant papaya is considered the best strategy for long-term virus control. Previous genetic studies of an interspecific mapping population of papaya relatives, Vasconcellea pubescens (resistant to PRSV-P) and V. parviflora (susceptible to PRSV-P), identified four markers linked to PRSV resistance in V. pubescens. One was a functional marker that collocated with prsv-1 exhibited homology to serine threonine protein kinase (STK) genes. It was considered to be a possible resistance gene candidate, as prsv-1 conferred immunity to the virus as a single dominant gene based on the segregation analysis. These genes are presumed to work together with a nucleotide binding site (NBS) gene involved in a guarding mechanism to provide resistance to the plant pathogenic organism. The regulation and functions of these putative R genes towards PRSV-P resistance in papaya could be determined through gene transformation without the need for backcrossing to recover an original phenotype in addition to saving a great deal of time that was previously required in extensive backcrossing programs.
Razali, R.H.M. and Drew, R. (2014). A REVIEW OF PRSV-P RESISTANCE GENES IN VASCONCELLEA SPECIES AND THEIR APPLICATION TO PRSV-P RESISTANCE IN CARICA PAPAYA. Acta Hortic. 1048, 65-74
papaya, Papaya ring spot virus, guarding mechanism, resistance gene candidate, transformation