Author
SAMTANI, JAYESH - Virginia Polytechnic Institution & State University | |
RACHUY, JOHN - University Of California | |
Mou, Beiquan | |
FENNIMORE, STEVEN - University Of California |
Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/14/2014 Publication Date: 7/1/2014 Citation: Samtani, J.B., Rachuy, J.S., Mou, B., Fennimore, S.A. 2014. Evaluation of tribenuron-methyl on sulfonylurea herbicide tolerant lettuce germplasm. Weed Technology. 28(3):510-517. Interpretive Summary: California lettuce growers have limited herbicide choices and there is no post-emergence herbicide available. The gene for sulfonylurea (SU) herbicide resistance discovered in a prickly lettuce population in Idaho was transferred to domestic lettuce by University of Idaho researchers. California researchers acquired the Idaho lettuce germplasm, “IDBR-1” and transferred the SU resistance gene to five common commercial lettuce types: butterhead, crisphead, green leaf, red leaf and romaine. Field trials were conducted at Salinas, CA during 2011 and 2012 to evaluate the tolerance of SU-susceptible and resistant lettuce types to post-emergence applications of a SU herbicide, Tribenuron-methyl. Treatments included a non-treated control, pronamide (standard herbicide) applied pre-emergence at 1.4 kg ai ha-1, and tribenuron-methyl at 0.004, 0.01, and 0.017 kg ha-1 applied post-emergence. Data collected were: weed control, injury estimates, lettuce stand counts, and lettuce yields. Injury to lettuce from tribenuron-methyl was high in SU-susceptible lettuce types and low in SU-tolerant lines. With the exceptions of some greenleaf and romaine lettuce lines that still may have some susceptible individuals, tribenuron-methyl did not reduce the stand or yield of SU-resistant lettuce, but did reduce the stand and yield of SU-susceptible lettuce. Tribenuron-methyl should be considered for registration as a lettuce herbicide for SU-tolerant lettuce types. This post-emergence herbicide gives lettuce growers more weed management options. Technical Abstract: The gene for sulfonylurea (SU) herbicide resistance discovered in a prickly lettuce population in Idaho was transferred to domestic lettuce by University of Idaho researchers. California researchers acquired the Idaho lettuce germplasm, “IDBR-1” and transferred the SU resistance gene to five common commercial lettuce types: butterhead, crisphead, green leaf, red leaf and romaine. Field trials were conducted at Salinas, CA during 2011 and 2012 to evaluate the tolerance of SU-susceptible and resistant lettuce types to postemergence applications of Tribenuron-methyl. Treatments included a non-treated control, pronamide applied preemergence at 1.4 kg ai ha-1, and tribenuron-methyl at 0.004, 0.01, and 0.017 kg ha-1 applied postemergence. Data collected were: weed control, injury estimates, lettuce stand counts, and lettuce yields. Injury to lettuce from tribenuron-methyl was high in SU-susceptible lettuce types and low in SU-tolerant lines. With the exceptions of some greenleaf and romaine lettuce lines that still may have some susceptible individuals, tribenuron-methyl did not reduce the stand or yield of SU-resistant lettuce, but did reduce the stand and yield of SU-susceptible lettuce. Tribenuron-methyl should be considered for registration as a lettuce herbicide for SU-tolerant lettuce types. |