Emergence timing and control of dandelion (Taraxacum officinale) using fall or spring applications of glyphosate and florasulam in spring wheat fields.

摘要

The control of dandelion (Taraxacum officinale Weber in Wiggers) in annual field crops can vary tremendously but the cause for this variation is unknown.; Field studies were conducted to determine the emergence period of dandelion arising either from seed or rootstock, and to determine the efficacy on dandelion of florasulam (a new ALS inhibitor with short soil residual activity) and glyphosate versus other herbicidal compounds applied at various rates in the fall (post-harvest) or spring (pre-seed). Results from the study show that dandelion emergence from rootstock was greatest early in the spring, commencing at less than 250 GDD, and diminished throughout the remainder of the year, while the majority of dandelion seedlings emerged at approximately 650 GDD, after the time when in-crop (post-emergence) herbicides would normally be applied. Differences in environmental conditions between the two years of the study (2003 and 2004) had a significant effect on dandelion flowering period and seedling survivorship. (Abstract shortened by UMI.)