Root growth profiles of Aveneae and Poeae plants in optically active α‐methylbenzyl‐3‐p‐tolylurea media

Abstract

Using a root growth inhibition assay, we studied the diverse chiral responses of plants in the tribes, Aveneae and Poeae, to the optically active compounds, R-and S-1-a-methylbenzyl-3-p-tolylurea (MBTU).We specifically examined the responses of grasses belonging to the Poeae tribe (Lolium, Briza, Poa, Dactylis, and Festuca) and the Aveneae tribe (Avena, Holcus, Agrostis, Alopecurus, Beckmannia, and Phleum). These plants include companion weeds of wheat and barley, and turf grass. The companion weeds of cereal crops, such as Poa annua, Poa pratensis, Dactylis glomerata, Avena fatua, Avena sativa, Holcus lanatus, Agrostis stolonifera, Alopecurus myosuroides, Al. aequalis, and Beckmannia syzigachne, showed significantly inhibited root growth in response to 20 mmol L -1 R-MBTU, whereas the root growth of Triticum aestivum was not inhibited at this concentration. Like Oryza sativa, almost all the Poeae and Aveneae plants tested here preferentially responded to R-MBTU, but the four grasses, Lolium multiflorum, D. glomerata, Alopecurus species, and Phleum pratense, preferentially responded to S-MBTU.Among them, the Agrostis species were highly sensitive to R-MBTU and the Alopecurus species were highly sensitive to S-MBTU. All the plants among the genera, Poa, Avena, and Alopecurus, showed a homogeneous chiral preference.