FUSARIUM WILT OF HERBS

A vascular wilt disease caused by the fungus Fusarium oxysporum has been reported on several species of herbs, including cumin (Cuminum cyminum), coriander (Coriandrum sativum), and Japanese mint (Mentha arvensis haplocalyx var. piperescens). None of the above mentioned disease, however, have been observed in the United States. A wilt disease of basil (Ocimum basilicum), caused by Fusarium oxysporum f. sp. basilicum, was first discovered in Russia in 1956. The disease has recently become a significant problem in the United States, and is being extensively studied at the University of Massachusetts. A survey of 28 commercial seed lots from four countries revealed that 59% of the lots exhibited 1 – 27 % Fusarium contamination. Methods of eliminating the causal agent from the basil seed through hot water and other treatments were investigated. Hot water treatments of 56 – 58°C for 20 minutes decreased Fusarium contamination by nearly 100%, without significantly affecting germination rates. A hot water treatment of 60°C for 20 minutes completely eliminated Fusarium; however, germination rates were decreased by approximately 56%.