Cutting the Gordian knot: taking a stab at corky root rot of tomato

Abstract

Corky root rot (CRR) is an escalating plant disease of tomato (Solanum esculentum), caused by a soil-borne fungus, Pyrenochaeta lycopersici. During the last two decades there have almost been no progress in the understanding of the molecular mechanisms promoting infection and plant susceptibility. As there are no CRR-resistant lines of cultivated tomato on the market and no other known means for plant protection, a deeper molecular knowledge about the infection process is urgently needed. We have therefore outlined an efficient strategy to search for corky root rot-resistance genes in wild tomato. In addition, we are investigating the genetic determinants for infection and virulence of the fungal pathogen, P. lycopersici. In this review we summarize the quite limited molecular knowledge about the pathogen and the disease, and discuss the possibilities to overcome previous technical obstacles in this new era of molecular biology.