Bacteria Causing Pith Necrosis and Tissue Discoloration in Tomato

Abstract

Tomato is one of the most widely cultivated and consumed vegetables in Costa Rica, where favorable environmental conditions enabled year-round production. However, these same conditions also promote the development of plant diseases. Diverse bacterial infections causing pith necrosis in tomato crops have become of frequent observation in recent years. Nevertheless, the causal agents in Costa Rica remain unidentified, and management strategies are poorly documented. This study evaluated the pathogenicity of bacterial isolates obtained from tomato plants collected in Costa Rica’s Central Valley. Isolates of Pseudomonas alliivorans, P. flavescens, and P. capsici were identified as causal agents of pith necrosis in tomatoes. Additionally, P. straminea and Cedecea sp. were associated with tissue discoloration. These findings provide valuable information to the tomato production sector in Costa Rica by identifying previously unreported pathogenic bacteria and expanding their known distribution and host ranges. These findings also demonstrate the ability of these isolates to cause pith necrosis.