Abstract

Peanut bud necrosis disease is one of the major diseases in peanut. Interspecific pre-breeding lines were identified as resistant to bud necrosis disease. Molecular diversity analysis in 115 lines resistant to bud necrosis disease using simple sequence repeat markers revealed wide genetic diversity among lines. Out of 219 bands amplified, 205 were found polymorphic. Polymorphism information content (PIC) value ranged from 0.5 to 0.94, with an average of 0.82. The cluster analysis and PCoA grouped 115 resistant lines and one susceptible cultivar into three major clusters sharing 58% similarity. Susceptible cultivar KRG-1 was distantly related to resistant lines NRCGCS-28 and NRCGCS-86. AMOVA predicted 96% variation within population and 4% among populations. NRCGCS-28 and NRCGCS-86 were found to be moderately resistant and KRG-1 as highly susceptible under artificially challenged inoculation conditions. The incubation period for appearance of disease symptoms were longer in NRCGCS-28 and NRCGCS-86 than KRG-1 under artificially challenged inoculation conditions. Thus, the present study reports additional sources for resistance to peanut bud necrosis disease (PBND).

Key Words: Peanut, peanut bud necrosis disease (PBND), simple sequence repeat (SSR), genetic diversity.

Abbreviation

Abbreviations: PBND, Peanut bud necrosis disease; PBNV, peanut bud necrosis virus; RAPD, random amplification of polymorphic DNA; ISSR, inter-simple sequence repeat; AFLP, amplified fragment length polymorphism; SSR, simple sequence repeat; CTAB, cetyle trimethyl ammonium bromide; PCR, polymerase chain reaction;  PIC, polymorphism information content; MI, marker Index; PCoA, principal coordinate analysis; AMOVA, analysis of molecular variance.