CONTROL OF XANTHOMONAS CAMPESTRIS pv. VIGNICOIA IN COWPEA FOLLOWING SEED AND SEEDLING TREATMENT WITH HYDROGEN PEROXIDE AND N-HETEROCYCLIC PYRIDINIUM CHLOROCHROMATE

• Published in: Journal of plant pathology Vol. 89; no. 3; pp. 361 - 367
• Main Authors: Kotchoni, O.S., Torimiro, N., Gachomo, E.W.
• Format: Journal Article
• Language: English
• Published: An International Journal of the Italian Phytopathological Society 01-11-2007
• Subjects: Blight; Chemical treatment; Fungal infections; Pathogens; Phytopathology; Plant diseases; Plants; Seedlings; Seeds; Sterilization
• ISSN: 1125-4653; 2239-7264

This study was carried out with the aim of assessing the antibacterial effect of hydrogen peroxide (H₂O₂) and N-heterocyclic pyridinium chlorochromate (PCC) on Xanthomonas campestris pv. vignicola, the causal agent of bacterial blight of cowpea. Disease severity in cowpea was analysed after seed and seedling treatment with the chemicals at different stages of growth. Pretreatment of cowpea seeds and seedlings with 1 mM H₂O₂ or PCC led to a reduced disease severity compared to untreated controls. A combination of H₂O₂ and PCC treatment conferred a better suppression of the disease in greenhouse trials than when H₂O₂ or PCC were used individually. In addition, the efficacy of PCC and H₂O₂ when used together to sterilise seeds was higher than that of sodium hypochlorite (NaOCl), a well-known seed sterilizer. The induction of NADHperoxidase activity mediating disease defence response in chemically treated cowpea seedlings is discussed. Our results suggest that PCC and H₂O₂ inhibited pathogen growth in seeds and seedlings and can be used to control seed-borne diseases under laboratory conditions.