2023-12-13 イリノイ大学アーバナ・シャンペーン校
◆研究では、49のトウモロコシ品種でトルピラテ感受性が確認され、通常はNsf1遺伝子によって引き起こされる感受性とは異なる遺伝的脆弱性が明らかになりました。トウモロコシ品種改良者や農家、化学企業に警鐘を鳴らし、今後のHPPD阻害剤の開発に対する遺伝的脆弱性の認識を促しています。感受性の生理的メカニズムや広がりについての更なる研究が必要とされています。
＜関連情報＞
- https://aces.illinois.edu/news/new-genetic-vulnerability-herbicide-found-nearly-50-sweet-and-field-corn-lines
- https://onlinelibrary.wiley.com/doi/10.1002/ps.7896
トウモロコシ（Zea mays）における重度のトルピラート感受性に関する初の報告により、除草剤に対する作物の反応をもたらす新たな遺伝的要因が発見された。 First report of severe tolpyralate sensitivity in corn (Zea mays) discovers a novel genetic factor conferring crop response to a herbicide Pest Management Science Published: 20 November 2023 DOI:https://doi.org/10.1002/ps.7896
Abstract
BACKGROUND
Tolpyralate, a relatively new inhibitor of 4-hydroxyphenylpyruvate dioxygenase (HPPD), is registered for postemergence use in all types of corn (Zea mays L.) and has a record of excellent crop tolerance. A report of severe crop injury to sweet corn inbred (XSEN187) led to the following objectives: (i) determine whether sensitivity to tolpyralate in XSEN187 exists, and if confirmed, (ii) determine the genetic basis of tolpyralate sensitivity, and (iii) screen other corn germplasm for sensitivity to tolpyralate.
RESULTS
Inbred XSEN187 was confirmed sensitive to tolpyralate. Inclusion of methylated seed oil or nonionic surfactant in the spray volume was necessary for severe crop injury. Tolpyralate sensitivity in XSEN187 is not conferred by alleles at Nsf1, a cytochrome P450-encoding gene (CYP81A9) conferring tolerance to many corn herbicides. Evidence suggests that tolpyralate sensitivity in XSEN187 is conferred by a single gene mapped to the Chr05: 283 240–1 222 909 bp interval. Moreover, tolpyralate sensitivity was observed in 48 other sweet corn and field corn inbreds.
CONCLUSIONS
Severe sensitivity to tolpyralate exists in sweet corn and field corn germplasm when the herbicide is applied according to label directions. Whereas the corn response to several other herbicides, including HPPD-inhibitors, is conferred by the Nsf1 locus, corn sensitivity to tolpyralate is the result of a different locus. The use of tolpyralate should consider herbicide tolerance in inbred lines from which corn hybrids were derived, whereas alleles that render corn germplasm sensitive to tolpyralate should be eliminated from breeding populations, inbreds, and commercial cultivars. © 2023 Illinois Foundation Seeds, Inc and The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
