銀膠菊(Parthenium hysterophorus L.)發芽特性及化學防治

Abstract

Parthenium weed is native to the subtropics of North and South America. It is regarded as one of the worst weeds in many countries because its invasiveness, potential for spread, and economic and environmental impacts. In this study, the effects of temperature, pH, osmotic potential and planting depth were determined for parthenium weed under controlled environments. The optimum temperatures for seed germination ranged from 12 to 28 ℃ of parthenium weed. Germination decreased between the water potentials -0.4 to -1.0 MPa, and germinated well between pH 5.5 and 9. Seedling emergence was maximum from soil surface on parthenium weed, no emerged seedling was observed buried beyond 1cm. We tested normal field used rate (x) and reduced rate (0.75x) of 12 herbicides on seeded parthenium weed. Pre-emergence test showed that atrazine, dimethenamid, diuron, metazachlor, metribuzin, oxyfluorfen provided 96.5% control and the same control in 0.75X rate. Post-emergence application of glufosinate, glyphosate, paraquat and metribuzin resulted in 85% reduction of fresh weight at 21 days after foliar application, pyrozosulfuron, triclopyr, 2,4D provided 70% control, and these herbicides at reduced rates were less effective.