El Niño-Southern Oscillation (ENSO): Impact on tomato spotted wilt intensity in peanut and the implication on yield

The impact of El Nino – Southern Oscillation (ENSO) on weather patterns could have cascading effects on several diseases of important crops in the southeastern United States. One such disease is spotted wilt of peanut caused by the Tomato spotted wilt virus (TSWV). Significant economic losses have been recorded by peanut growers in the southeastern United States since the disease was first reported in 1986. The virus is transmitted by western flower thrips Frankliniella occidentalis and tobacco thrips, Frankliniella fusca . The objective of this study was to examine the influence of El Nino – Southern Oscillation on spotted wilt intensity and peanut yield. Our analysis was based on field trials conducted between 1994 and 2005 at field locations in Georgia and Florida in the United States. The spotted wilt intensity (%) in two peanut genotypes and the corresponding yield were recorded and evaluated. Each season was categorized by ENSO (El Nino, Neutral or La Nina) based on the NOAA Climate Prediction Center classification scheme. Results showed that the interaction between ENSO and peanut genotypes significantly affected spotted wilt intensity. Spotted wilt intensity was significantly lower during La Nina when compared to El Nino or Neutral years. The results also showed a significant correlation between spotted wilt intensity and peanut yield. Incorporating findings from this study into the existing TWSV risk index could aid peanut producers in making management decisions for reducing spotted wilt.