- Author: Brad Hanson
In late 2016 and early 2017, the Weed Science Society of America (WSSA) organized a series of seven "Herbicide Resistance Listening Sessions" around the country.
Brian Schutte (from New Mexico State University) and I co-hosted the Southwestern session in Tulare, CA on February 15, 2017 and, if you're a regular reader, this may sound vaguely familiar since I tried to drum up interest on the blog in November 2016 and Pratap shared
- Author: Lynn M. Sosnoskie
Glyphosate was commercialized in 1974. Since then, it has become one of the most widely used (and studied) herbicides. According to Duke (2018b), almost 20,000 scientific publications and patents have included glyphosate as a focus; only 2,4-D surpasses it with respect to citations. The articles in the 5th issue of the 74th volume of Pest Management Science all focus on glyphosate and arose from a day long symposium (which was also dedicated to the molecule) that was held at the 252nd annual meeting of the American Chemical Society (Duke 2018a).
Figure 1. The...
- Posted by: Gale Perez
Be sure to check out the following articles in the Good Fruit Grower magazine (April 24, 2018)
Herbicide resistance pushes California grape growers to try bringing back weed control strategies such as sheep and cultivation -- UC Cooperative Extension Weed Science Advisor John Roncoroni quoted in article
The evolution of herbicide resistance in weeds is an ongoing problem in California agriculture. Resistance to glyphosate has become particularly widespread across the state. Normally, glyphosate kills weedy plants by inhibiting 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an enzyme that is necessary for the production of some important amino acids in plants. However, repeated applications of glyphosate can result in the selection of rare mutant plants that have a unique ability (mechanism) to “resist” death by glyphosate. The mutant plants survive glyphosate application and produce seeds, which give rise to more resistant plants the following year. Over time, repeated glyphosate applications will result in a field,...
- Author: Mariano Galla
Italian ryegrass (Lolium perenne spp. Multiflorum), is an annual grass common in Sacramento Valley orchard and field crops (Figure 1). This species germinates and matures approximately at the same time as winter cereals and is highly competitive for soil nutrients during the time when wheat is tillering. It can also interfere with harvest and it has been reported that Italian ryegrass can cause up to 80% reduction in winter wheat grain yield due to competition for nutrients and water (Liu et al., 2016)
During this time of the year when your wheat is tillering, it is really important to monitor fields for weeds and Italian ryegrass infestations in particular.
Information about weed management can...