ISSN:
1432-2242
Keywords:
Conyza bonariensis
;
Superoxide-dismutase
;
Glutathione-reductase
;
Ascorbate-peroxidase
;
Paraquat resistance
;
Oxygen-radical detoxification
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary The genetics of paraquat-resistance in Conyza bonariensis was studied. Reciprocal crosses were prepared between resistant and sensitive individuals. The enzymes of the pathway that detoxifies superoxide to innocuous oxygen species involved in resistance were evaluated in the F1 and F2 generations. All F1 plants were as resistant as the resistant parent, irrespective of parental sex, demonstrating dominance and excluding maternal inheritance. The activities of superoxide-dismutase, ascorbate-peroxidase and glutathione-reductase in the F1 were constitutively as high as in the resistant parent. Resistance in the F2 generation was distributed in a 3∶1 ratio (resistant to sensitive). Leaves from F2 plants were removed for a resistance assay and enzyme immuno-assays of single plants were performed. The high levels of superoxide-dismutase and glutathione-reductase, the two enzymes for which antibodies were available, were similar in resistant individuals to the levels in the resistant parent; the levels were low in the susceptible individuals. These results indicate either a very tight linkage, or more probably, that one dominant nuclear gene controls resistance by pleiotropically controlling the levels of enzymes of the activeoxygen detoxification pathway.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00258044
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