Brabham Chad, Norsworthy Jason K, González-Torralva Fidel
Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR 72704, USA.
Plants (Basel). 2020 Nov 14;9(11):1576. doi: 10.3390/plants9111576.
Benzobicyclon has shown varying results in controlling weedy rice, including those with imidazolinone (IMI) resistance. Tolerance to benzobicyclon in cultivated rice, but not or -like cultivars, is conferred by a fully functional () gene. Herein, a diagnostic Kompetitive Allele Specific PCR (KASP) assay was developed to predict the genotype of weedy rice plants from 37 accessions and correlated to their response to benzobicyclon in the field. Two-thirds of the 693 weedy rice plants screened were tolerant to benzobicyclon (371 g ai ha, SC formulation) at 30 days after treatment (DAT). Thirty-four percent of plants were homozygous for the allele and 98% of these plants exhibited field tolerance. However, the genotype did not always correlate with field data. Only 52% of plants were considered sensitive, indicating that the single nucleotide polymorphisms (SNPs) chosen in the KASP assay are not a reliable tool in predicting homozygous plants. In an additional experiment, 86% of the 344 plants with at least one copy of the ALS trait harbored a allele, suggesting fields infested with IMI herbicide-resistant weedy rice are unlikely to be controlled with benzobicyclon.
双环苯草酮在控制杂草稻方面表现出不同的效果，包括那些对咪唑啉酮（IMI）具有抗性的杂草稻。栽培稻对双环苯草酮具有耐受性，但粳稻品种或类似品种则不然，这是由一个功能完整的（）基因赋予的。在此，开发了一种诊断性竞争性等位基因特异性PCR（KASP）检测方法，以预测来自37个种质的杂草稻植株的基因型，并将其与它们在田间对双环苯草酮的反应相关联。在处理后30天（DAT），筛选的693株杂草稻植株中有三分之二对双环苯草酮（371克活性成分/公顷，悬浮剂配方）具有耐受性。34%的植株为等位基因纯合子，其中98%的植株表现出田间耐受性。然而，基因型并不总是与田间数据相关。只有52%的植株被认为是敏感的，这表明KASP检测中选择的单核苷酸多态性（SNP）并不是预测纯合植株的可靠工具。在另一项实验中，344株至少有一个ALS性状拷贝的植株中有86%携带等位基因，这表明用双环苯草酮不太可能控制受IMI除草剂抗性杂草稻侵染的田地。
