Investigation of physiological and molecular mechanisms conferring diurnal variation in auxinic herbicide efficacy.

The efficacy of auxinic herbicides, a valuable weed control tool for growers worldwide, has been shown to vary with the time of day in which applications are made. However, little is known about the mechanisms causing this phenomenon. Investigating the differential in planta behavior of these herbicides across different times of application may grant an ability to advise which properties of auxinic herbicides are desirable when applications must be made around the clock.

Gene amplification confers glyphosate resistance in Amaranthus palmeri.

The herbicide glyphosate became widely used in the United States and other parts of the world after the commercialization of glyphosate-resistant crops. These crops have constitutive overexpression of a glyphosate-insensitive form of the herbicide target site gene, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Increased use of glyphosate over multiple years imposes selective genetic pressure on weed populations.

Human oncogenes detected by a defined medium culture assay.

Oncogenes in DNAs from human tumor cell lines have been detected by a new transformation assay. Cellular DNAs are transfected into NIH3T3 murine fibroblasts, and transformed cells are selected by maintaining cell cultures in a defined medium lacking platelet-derived or fibroblast growth factors. DNAs from eight of 17 human tumor cell lines have yielded transformants by this method.