Journal of Plant Pathology & Microbiology

Assessing root and shoot traits associated with herbicide resistance in weeds

International Conference on Plant Physiology & Pathology

June 09-10, 2016 Dallas, USA

Te-Ming Tseng

Mississippi State University, USA

Posters & Accepted Abstracts: J Plant Pathol Microbiol

Abstract:

As the incidences of herbicide resistance in weeds continue to worsen, the necessity to screen weed samples for herbicide resistance has become more important. Numerous techniques have evolved that can confirm herbicide resistance in weed species. However, most of these techniques either take long to complete (3-5 weeks), or lack strong association of shoot and root traits with herbicide resistance. In this study, we used annual bluegrass as a model weed to demonstrate rapid root and shoot phenotyping for herbicide resistance. Acetolactate synthase (ALS) inhibitors are most commonly used for control of annual bluegrass. However, repeated usage of these herbicides has resulted in resistance reported in Alabama, Tennessee, and Mississippi. The objectives of this study is to develop a rapid Murashige and Skoog (MS) plate assay for herbicide resistant trait, which can then be used for confirming resistance of any annual bluegrass sample from residential or commercial turfgrass, in less than two weeks. Greenhouse dose response studies revealed resistant population (Reunion) to be 45 times more resistant to foramsulfuron than the susceptible annual bluegrass population (commercially purchased). The resistant population requires 331 g of foramsulfuron ha-1, whereas the susceptible population only requires 7.2 g of foramsulfuron ha-1, to achieve 50% control. For the plate assay, plants were grown in MS medium, and three inoculation techniques were tested. The seed and root tip inoculation proved to be the most effective in discriminating between resistant and susceptible population. Total time involved from planting of seed to confirming resistance was about 2 weeks. Daily non-destructive root scans were able to identify changes in root characteristics (number of laterals, root length, root area, and root growth rate) between resistant and susceptible population. This plate assay can potentially be used with any weed species to effectively detect resistance trait, and can be combined with molecular assays to further confirm resistance.

Biography :

Email: tt1024@msstate.edu