CHEMICAL AND PHYSICAL DISINFECTION OF PEANUT PODS FOR IMPROVED SEED QUALITY

Peanut pod wart is a new disease in Israel that causes ugly warts on t he pod. The causal agent, Streptomyces sp., contaminates seed during m echanical cracking of pods. Low-volume application of 3% iodine dissol ved in glacial acetic acid resulted in effective pod disinfection and reduced the surface pods microflora by 4 log orders, but this mixture causes eye irritation and has an unpleasant smell. A 4 s exposure of t he pods to a butane-air flame at 740 degrees C eradicated the pathogen and even a 6 s exposure did not affect seed germination or yield. Thi s physical treatment also reduced significantly the incidence of other seedborne fungi, e.g. Aspergillus niger and Rhizopus stolonifer, in t he laboratory and in a large-scale field test. Flaming enables the tre atment of large quantities of pods prior to cracking. (C) 1997 Elsevie r Science Ltd.