Submitted to: Weed Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/1997
Publication Date: N/A
Citation: AL-KHATIB, K., LIBBEY, C., KADIR, S., BOYDSTON, R.A. DIFFERENTIAL VARIETAL RESPONSE OF GREEN PEA (PISUM SATIVUM) TO METRIBUZIN. WEED TECHNOLOGY. 11:775-781. 1997. Interpretive Summary: Weed Control in green peas is mainly accomplished with herbicides. Metribuzin herbicide is labeled for weed control in green peas, but often can injure the crop depending on the weather, soil type, and pea variety. Knowing which pea varieties are the most sensitive to metribuzin and what environmental conditions contribute to metribuzin injury could help growers adjust herbicide rates to minimize pea injury. Fifteen green pea varieties were ranked according to their response to metribuzin. Four pea varieties were ranked tolerant and two were ranked susceptible to metribuzin. Peas grown under warmer temperatures were injured more by metribuzin as were peas grown in soil watered to field capacity. With this information growers can avoid using metribuzin or reduce metribuzin rates on susceptible pea varieties and when soils are saturated or warm weather is expected.
Technical Abstract: Field and green house experiments evaluated the differential response of 15 green pea varieties to metribuzin applied preemergence. 'Charo,' 'CMG 298', 'Leah,' 'Scout,' and 'Puget' were the most tolerant, whereas 'Bolero' and 'Sundance' were the most susceptible varieties under greenhouse conditions. Variable chlorophyll fluorescence efficiency of photosystem II, and leaf area were reduced sharply by metribuzin in susceptible varieties and metribuzin susceptibility correlated highly with the reduction in shoot dry weight. Green pea varieties grown under field conditions responded to metribuzin similarly to pea varieties grown under greenhouse conditions. Metribuzin reduced shoot dry weight more in peas grown at 30/25 C than in those grown at 25/20 and 20/15 C. Also, metribuzin injured peas more when grown in soil watered to field capacity compared to soil at 70 and 40% of field capacity.