THE MECHANISM OF RESISTANCE TO PARAQUAT IS STRONGLY TEMPERATURE-DEPENDENT IN RESISTANT HORDEUM-LEPORINUM LINK AND H-GLAUCUM STEUD

E Purba, C Preston, Stephen Powles

    Research output: Contribution to journalArticle

    39 Citations (Scopus)

    Abstract

    Paraquat-resistant biotypes of the closely-related weed species Hordeum leporinum Link and H. glaucum Steud. are highly resistant to paraquat when grown during the normal winter growing season. However, when grown and treated with paraquat in summer, these biotypes are markedly less resistant to paraquat. This reduced resistance to paraquat in summer is primarily a result of increased temperature following herbicide treatment. The mechanism governing this decrease in resistance at high temperature was examined in H. leporinum. No differences were observed between susceptible and resistant biotypes in the interaction of paraquat with isolated thylakoids when assayed at 15, 25, or 35 degrees C. About 98 and 65% of applied paraquat was absorbed through the leaf cuticle of both biotypes at 15 and 30 degrees C, respectively. Following application to leaves, more herbicide was translocated in a basipetal direction in the susceptible biotype compared to the resistant biotype at 15 degrees C. However, at 30 degrees C more paraquat was translocated in a basipetal direction in the resistant biotype. Photosynthetic activity of young leaf tissue from within the leaf sheath which had not been directly exposed to paraquat was measured 24 h after treatment of plants with paraquat. This activity was inhibited in the susceptible biotype when plants were maintained at either 15 degrees C or 30 degrees C after treatment. In contrast, photosynthetic activity of such tissue of the resistant biotype was not inhibited when plants were maintained at 15 degrees C after treatment, but was inhibited at 30 degrees C. The mechanism of resistance in this biotype of H. leporinum correlates with decreased translocation of paraquat and decreased penetration to the active site. This mechanism is temperature sensitive and breaks down at higher temperatures.
    Original languageEnglish
    Pages (from-to)464-468
    JournalPlanta
    Volume196
    Publication statusPublished - 1995

    Fingerprint

    Hordeum murinum subsp. leporinum
    Paraquat
    paraquat
    Hordeum
    resistance mechanisms
    biotypes
    Temperature
    temperature
    Herbicides
    Hordeum murinum subsp. glaucum
    leaves
    herbicides
    Thylakoids
    summer
    thylakoids
    active sites

    Cite this

    @article{19040e3d69b3493eb606d4434359ff85,
    title = "THE MECHANISM OF RESISTANCE TO PARAQUAT IS STRONGLY TEMPERATURE-DEPENDENT IN RESISTANT HORDEUM-LEPORINUM LINK AND H-GLAUCUM STEUD",
    abstract = "Paraquat-resistant biotypes of the closely-related weed species Hordeum leporinum Link and H. glaucum Steud. are highly resistant to paraquat when grown during the normal winter growing season. However, when grown and treated with paraquat in summer, these biotypes are markedly less resistant to paraquat. This reduced resistance to paraquat in summer is primarily a result of increased temperature following herbicide treatment. The mechanism governing this decrease in resistance at high temperature was examined in H. leporinum. No differences were observed between susceptible and resistant biotypes in the interaction of paraquat with isolated thylakoids when assayed at 15, 25, or 35 degrees C. About 98 and 65{\%} of applied paraquat was absorbed through the leaf cuticle of both biotypes at 15 and 30 degrees C, respectively. Following application to leaves, more herbicide was translocated in a basipetal direction in the susceptible biotype compared to the resistant biotype at 15 degrees C. However, at 30 degrees C more paraquat was translocated in a basipetal direction in the resistant biotype. Photosynthetic activity of young leaf tissue from within the leaf sheath which had not been directly exposed to paraquat was measured 24 h after treatment of plants with paraquat. This activity was inhibited in the susceptible biotype when plants were maintained at either 15 degrees C or 30 degrees C after treatment. In contrast, photosynthetic activity of such tissue of the resistant biotype was not inhibited when plants were maintained at 15 degrees C after treatment, but was inhibited at 30 degrees C. The mechanism of resistance in this biotype of H. leporinum correlates with decreased translocation of paraquat and decreased penetration to the active site. This mechanism is temperature sensitive and breaks down at higher temperatures.",
    author = "E Purba and C Preston and Stephen Powles",
    year = "1995",
    language = "English",
    volume = "196",
    pages = "464--468",
    journal = "Planta - an international journal of plant biology",
    issn = "0032-0935",
    publisher = "Springer",

    }

    THE MECHANISM OF RESISTANCE TO PARAQUAT IS STRONGLY TEMPERATURE-DEPENDENT IN RESISTANT HORDEUM-LEPORINUM LINK AND H-GLAUCUM STEUD. / Purba, E; Preston, C; Powles, Stephen.

    In: Planta, Vol. 196, 1995, p. 464-468.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - THE MECHANISM OF RESISTANCE TO PARAQUAT IS STRONGLY TEMPERATURE-DEPENDENT IN RESISTANT HORDEUM-LEPORINUM LINK AND H-GLAUCUM STEUD

    AU - Purba, E

    AU - Preston, C

    AU - Powles, Stephen

    PY - 1995

    Y1 - 1995

    N2 - Paraquat-resistant biotypes of the closely-related weed species Hordeum leporinum Link and H. glaucum Steud. are highly resistant to paraquat when grown during the normal winter growing season. However, when grown and treated with paraquat in summer, these biotypes are markedly less resistant to paraquat. This reduced resistance to paraquat in summer is primarily a result of increased temperature following herbicide treatment. The mechanism governing this decrease in resistance at high temperature was examined in H. leporinum. No differences were observed between susceptible and resistant biotypes in the interaction of paraquat with isolated thylakoids when assayed at 15, 25, or 35 degrees C. About 98 and 65% of applied paraquat was absorbed through the leaf cuticle of both biotypes at 15 and 30 degrees C, respectively. Following application to leaves, more herbicide was translocated in a basipetal direction in the susceptible biotype compared to the resistant biotype at 15 degrees C. However, at 30 degrees C more paraquat was translocated in a basipetal direction in the resistant biotype. Photosynthetic activity of young leaf tissue from within the leaf sheath which had not been directly exposed to paraquat was measured 24 h after treatment of plants with paraquat. This activity was inhibited in the susceptible biotype when plants were maintained at either 15 degrees C or 30 degrees C after treatment. In contrast, photosynthetic activity of such tissue of the resistant biotype was not inhibited when plants were maintained at 15 degrees C after treatment, but was inhibited at 30 degrees C. The mechanism of resistance in this biotype of H. leporinum correlates with decreased translocation of paraquat and decreased penetration to the active site. This mechanism is temperature sensitive and breaks down at higher temperatures.

    AB - Paraquat-resistant biotypes of the closely-related weed species Hordeum leporinum Link and H. glaucum Steud. are highly resistant to paraquat when grown during the normal winter growing season. However, when grown and treated with paraquat in summer, these biotypes are markedly less resistant to paraquat. This reduced resistance to paraquat in summer is primarily a result of increased temperature following herbicide treatment. The mechanism governing this decrease in resistance at high temperature was examined in H. leporinum. No differences were observed between susceptible and resistant biotypes in the interaction of paraquat with isolated thylakoids when assayed at 15, 25, or 35 degrees C. About 98 and 65% of applied paraquat was absorbed through the leaf cuticle of both biotypes at 15 and 30 degrees C, respectively. Following application to leaves, more herbicide was translocated in a basipetal direction in the susceptible biotype compared to the resistant biotype at 15 degrees C. However, at 30 degrees C more paraquat was translocated in a basipetal direction in the resistant biotype. Photosynthetic activity of young leaf tissue from within the leaf sheath which had not been directly exposed to paraquat was measured 24 h after treatment of plants with paraquat. This activity was inhibited in the susceptible biotype when plants were maintained at either 15 degrees C or 30 degrees C after treatment. In contrast, photosynthetic activity of such tissue of the resistant biotype was not inhibited when plants were maintained at 15 degrees C after treatment, but was inhibited at 30 degrees C. The mechanism of resistance in this biotype of H. leporinum correlates with decreased translocation of paraquat and decreased penetration to the active site. This mechanism is temperature sensitive and breaks down at higher temperatures.

    M3 - Article

    VL - 196

    SP - 464

    EP - 468

    JO - Planta - an international journal of plant biology

    JF - Planta - an international journal of plant biology

    SN - 0032-0935

    ER -