Research Probes Herbicide Safety, Timing for Specialty Crops
Why is this important? Aggressive weed competition for light, water, and nutrients is a major concern for both snap bean and beet crops, necessitating a heavy reliance on synthetic herbicides to maintain yields and quality.
In the study, "Snap Bean (Phaseolus vulgaris L.) Response to Postemergence Herbicides at Different Growth Stages," researchers evaluated how snap beans respond to applications of bentazon, fomesafen, and imazamox applied alone or in combination-at multiple crop growth stages. Results showed that applying too early, particularly at the cotyledon or unifoliate stages, increased crop injury and reduced yield. The safest and most consistent performance occurred when herbicides were applied after the first trifoliate leaf had fully expanded. Bentazon alone caused the least injury and preserved yield most effectively, whereas combinations containing fomesafen or imazamox resulted in greater phytotoxicity and yield reductions when applied prematurely. The findings reinforce the importance of adhering to labeled growth-stage recommendations to minimize crop stress.
A companion study, "Performance and Safety of Acifluorfen in Processing Red Beets," examined the effectiveness and crop safety of acifluorfen a herbicide that has been explored for use in sugar beets for controlling problematic pigweed species in processing red beet production. Field trials demonstrated strong control of Powell amaranth, particularly at higher application rates. The herbicide was less effective
against common ragweed. However, early applications (4-6 leaf crop growth stage) and higher rates also increased the risk of leaf injury and stunting in red beets. Later applications, at the 10-12 leaf stage, significantly reduced crop injury and helped preserve root yield, although injury impacts could be amplified by weather conditions. The herbicide was less effective against common ragweed, underscoring the need for integrated weed management strategies.
Together, these findings contribute to a clearer understanding of how herbicide selection and application timing affect two important specialty crops. By identifying safe and effective practices, this research supports efforts to optimize weed management while safeguarding crop performance and grower profitability.
Lynn Sosnoskie is Assistant Professor in the School of Integrative Plant Science, at Cornell University. Her work includes tree and vine drops in addition to fresh and processing vegetables.
Co-authors include Thierry Besancon, Associate Professor at Rutgers University, Mark VanGessel, Professor at the University of Delaware, and Dwight Lingenfelter, Extension Associate at Penn State University.
The full article can be read on the ASHS HortTech electronic Journal website at: https://doi.org/10.21273/HORTTECH05669-25 and https://doi.org/10.21273/HORTTECH05667-25
Established in 1903, the American Society for Horticultural Science is recognized around the world as one of the most respected and influential professional societies for horticultural scientists. ASHS is committed to promoting and encouraging national and international interest in scientific research and education in all branches of horticulture.
Comprised of thousands of members worldwide, ASHS represents a broad cross-section of the horticultural community-scientists, educators, students, landscape and turf managers, government, extension agents and industry professionals. ASHS members focus on practices and problems in horticulture: breeding, propagation, production and management, harvesting, handling and storage, processing, marketing and use of horticultural plants and products. To learn more, visit ashs.org.
https://ashs.org/news/news.asp?id=720613
View Original | AusPol.co Disclaimer