Peanut bud necrosis disease (PBND) caused by Peanut bud necrosis virus (PBNV) is an important disease of peanut (Arachis hypogaea L.) in Thailand especially during the dry season. Host plant resistance is one of the effective methods to control the disease. The objectives of this study were to estimate broad sense heritability and to evaluate phenotypic and genotypic correlation between PBND score and PBND incidence in the F4 generation of 10 crosses of peanut. A randomized complete block design with 4 replications was used for testing the mentioned F3 families in F4 generation at two locations in Kalasin province in the Northeast of Thailand. Characters under study were PBND score and PBND incidence (percent infected plants) evaluated at 30, 40, 50, 60, 70, and 90 days after sowing (DAS). The 50 and 60 day data are reported herein. There were significant differences among crosses for PBND score and PBND incidence. Means for PBND score and PBND incidence of resistant x susceptible group were intermediate between resistant x resistant group and susceptible x susceptible one. ICGV 86388 x IC 34 and IC 10 x KK 4 had lower PBND score and PBND incidence than the other crosses. Heritability estimates for PBND score and PBND incidence evaluated at 50 and 60 DAS were moderate to high, ranging from 0.27 to 0.90, revealing that families that had low PBND score and PBND incidence could be readily identified in the F4 generation. Phenotypic and genotypic correlations between PBND score and PBND incidence were closely associated, indicating that single parameter evaluation is sufficient. PBND incidence is more suitable than PBND score because of its simplicity.
