Alligatorweed Produces Viable Stem Fragments in Response to Herbicide Treatment

作者：Dugdale Tony M^*; Clements D; Hunt T D; Butler K L

来源：Journal of Aquatic Plant Management, 2010, 48: 84-91.

• allofragments
• Alternanthera philoxeroides
• autofragments
• diclobenil
• eradication
• glyphosate
• metsulfuron-methyl

Alligatorweed (Alternanthera philoxeroides [Mart.] Griseb.) is subject to an eradication program in Victoria, Australia. In aquatic situations the herbicides glyphosate (N-(phosphonomethyl) glycine, present as the isopropylamine salt) or metsulfuron-methyl (2-(4-methoxy-6-methyl-1,3,5-triazin-2-yl-carbamoylsulfamoyl) benzoic acid) are used. Anecdotal observations suggest that herbicide application results in the production of many alligatorweed stem fragments and that some of these are viable and capable of colonization. We applied herbicide to alligatorweed growing in waterlogged containers (glyphosate, mesulfuron-methyl and dichlobenil (2,6-dichlorobenzonitrile)) and collected the resulting stem fragments. Herbicide treatment resulted in many more stem fragments than no herbicide treatment, with 382 stem fragments m(-2) for glyphosate-treated plants, 165 m-2 for metsulfuron-methyl, 129 m(-2) for dichlobenil, and 7 m(-2) for untreated plants. A proportion of stem fragments collected were viable and varied between herbicides (2, 41, 1, and 23% for glyphosate, metsulfuron-methyl, dichlobenil and untreated plants, respectively). Overall viable stem fragment production was greatest for metsulfuron-methyl-treated plants, which produced 66 m(-2) viable stem fragments compared to 9 m(-2) for glyphosate and 3 m(-2) for dichlobenil and untreated plants. We also applied glyphosate or metsulfuron-methyl to patches of alligatorweed in field situations. A high proportion of stem fragments were viable (60 to 80%), regardless of herbicide used, for patches >5 m(2). For patches <5 m(2), viability was low (<5%). We postulate that viable fragments are produced by a combination of poor herbicide coverage to lower stems and poor translocation of herbicide within the plant. Successful aquatic alligatorweed eradication programs will require actions to manage viable stem fragment production.

• 出版日期2010-7