Oligogenic Inheritance of Resistance to Plum Pox Virus in Apricots

Abstract

In order to determine the inheritance of resistance to PPV in apricot three crosses between resistant and susceptible cultivars and selections were performed. The B1 seedlings were inoculated with the PPV-M strain by an infected bud. PPV infection was evaluated over 5 consecutive growth periods through visual symptoms, ELISA and in some cases reverse transcriptase PCR assays. Chi-square analysis of each B1 progeny was performed to determine if the segregation ratio differed from the expected ratio. PPV resistance segregated in three apricot B1progenies in a 1:7 (resistant:susceptible) ratio, indicating that resistance was controlled by three independent dominant complementary genes. All three dominant genes are needed for the resistance to be expressed, and the lack of any one of the dominant alleles will result in susceptibility. This knowledge will help us in effective planning of apricot breeding programs with this subjective.

Keywords

• prunus armeniaca l.
• heritability
• sharka disease