Xu Hongle, Zhang Wenpan, Zhang Teng, Li Jun, Wu Xian, Dong Liyao
College of Plant Protection, Nanjing Agricultural University, Nanjing, China; Key Laboratory of Integrated Pest Management on Crops in East China (Nanjing Agricultural University), Ministry of Agriculture, Beijing, China.
College of Plant Protection, Nanjing Agricultural University, Nanjing, China; National Key Laboratory of Crop Genetic & Germplasm Enhancement, Cotton Research Institute, Nanjing Agricultural University, Nanjing, China.
PLoS One. 2014 Dec 11;9(12):e114712. doi: 10.1371/journal.pone.0114712. eCollection 2014.
Ploidy level is important in biodiversity studies and in developing strategies for isolating important plant genes. Many herbicide-resistant weed species are polyploids, but our understanding of these polyploid weeds is limited. Japanese foxtail, a noxious agricultural grass weed, has evolved herbicide resistance. However, most studies on this weed have ignored the fact that there are multiple copies of target genes. This may complicate the study of resistance mechanisms. Japanese foxtail was found to be a tetraploid by flow cytometer and chromosome counting, two commonly used methods in the determination of ploidy levels. We found that there are two copies of the gene encoding plastidic acetyl-CoA carboxylase (ACCase) in Japanese foxtail and all the homologous genes are expressed. Additionally, no difference in ploidy levels or ACCase gene copy numbers was observed between an ACCase-inhibiting herbicide-resistant and a herbicide-sensitive population in this study.
倍性水平在生物多样性研究以及制定分离重要植物基因的策略方面都很重要。许多抗除草剂杂草物种都是多倍体，但我们对这些多倍体杂草的了解有限。有害农业禾本科杂草日本狗尾草已进化出抗除草剂能力。然而，大多数关于这种杂草的研究都忽略了目标基因存在多个拷贝这一事实。这可能会使抗性机制的研究变得复杂。通过流式细胞仪和染色体计数这两种常用于确定倍性水平的方法，发现日本狗尾草是四倍体。我们发现日本狗尾草中编码质体乙酰辅酶A羧化酶（ACCase）的基因有两个拷贝，并且所有同源基因都有表达。此外，在本研究中，对ACCase抑制型抗除草剂种群和除草剂敏感种群之间的倍性水平或ACCase基因拷贝数未观察到差异。
