Resistance to paraquat in Mazus pumilus

• Published in: Weed research Vol. 53; no. 3; pp. 176 - 182
• Main Authors: Tsuji, K, Hosokawa, M, Morita, S, Miura, R, Tominaga, T
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01.06.2013; Wiley-Blackwell; Wiley Subscription Services, Inc
• Subjects: antioxidative enzymes; Biological and medical sciences; Chemical control; chlorophyll; ferric reducing antioxidant power; Fundamental and applied biological sciences. Psychology; Japanese Mazus; methyl viologen; Parasitic plants. Weeds; Phytopathology. Animal pests. Plant and forest protection; superoxide dismutase; Weeds; Chlorophyll; Enzyme; Biochemical compound; Pesticides; Japanese Mazus; Superoxide dismutase; Systemic; Antioxidant; Herbicide; antioxidative enzymes; Quaternary ammonium compound; Chemical reduction; Resistance; Iron III; methyl viologen; Chemical reaction; Photosynthetic pigment; Weed science; Paraquat; ferric reducing antioxidant power; Oxidoreductases
• ISSN: 0043-1737; 1365-3180
• DOI: 10.1111/wre.12012

Summary Mazus pumilus is an annual self‐pollinating weed that is commonly found in arable land, vegetable gardens and roadsides. This weed harbours insects and pathogens that attack vegetables. The mechanism of resistance to paraquat of M. pumilus found in Ohita, Japan, was studied. Whole plant bioassays revealed that the resistant (R) biotypes were four to six times less susceptible than controls. Chlorophyll destruction of leaf discs by paraquat treatment in R biotypes was 4–20 times lower than those of susceptible (S) biotypes. Ferric reducing antioxidant power (FRAP) values in R biotypes were higher than those of S biotypes before and after paraquat treatments. The activity of superoxide dismutase (SOD) was also higher in R biotypes than those of S biotypes before and after treatment with paraquat, but the activities of ascorbate peroxidase (APX) and catalase (CAT) were not different between R and S biotypes. Change of ascorbate (AsA) contents before and after paraquat treatment was equivalent in both biotypes. These results indicate that the increased SOD activity and antioxidant capacity in R biotypes contribute to the resistance to paraquat of M. pumilus.