Matiru Viviene N, Dakora Felix D
Botany Department, University of Cape Town, Private Bag, Rondebosch 7701, South Africa.
New Phytol. 2005 May;166(2):439-44. doi: 10.1111/j.1469-8137.2005.01344.x.
The stimulatory role of lumichrome, a rhizosphere metabolite, was assessed on the growth of legume and cereal seedlings. At a very low nanomolar concentration (5 nm), lumichrome elicited growth promotion in cowpea, soybean, sorghum, millet and maize, but not in common bean, Bambara groundnut and Sudan grass. In soybean and cowpea only, 5 nm lumichrome caused early initiation of trifoliate leaf development, expansion in unifoliate and trifoliate leaves, increased stem elongation and, as a result, an increase in shoot and plant total biomass relative to control. Lumichrome (5 nm) also increased leaf area in maize and sorghum, and thus raised shoot and total biomass but there was no effect on the leaf area of the other cereals. Root growth was also stimulated in sorghum and millet by the supply of 5 nm lumichrome. By contrast, the application of a higher dose of lumichrome (50 nm) depressed development of unifoliate leaves in soybean, the second trifoliate leaf in cowpea, and shoot biomass in soybean. The 50 nm concentration also consistently decreased root development in cowpea and millet, but had no effect on the other species. These data show that lumichrome is a rhizosphere signal molecule that affects seedling development in both monocots and dicots.
对根际代谢物核黄素对豆类和谷类幼苗生长的刺激作用进行了评估。在极低的纳摩尔浓度（5纳米）下，核黄素促进了豇豆、大豆、高粱、粟和玉米的生长，但对菜豆、斑巴拉花生和苏丹草没有促进作用。仅在大豆和豇豆中，5纳米的核黄素导致三出复叶发育提前启动，单叶和三出复叶展开，茎伸长增加，结果相对于对照，地上部和植株总生物量增加。5纳米的核黄素还增加了玉米和高粱的叶面积，从而提高了地上部和总生物量，但对其他谷类作物的叶面积没有影响。供应5纳米的核黄素也刺激了高粱和粟的根系生长。相比之下，施用较高剂量的核黄素（50纳米）会抑制大豆单叶的发育、豇豆第二片三出复叶的发育以及大豆地上部生物量。50纳米的浓度也持续降低了豇豆和粟的根系发育，但对其他物种没有影响。这些数据表明，核黄素是一种根际信号分子，影响单子叶植物和双子叶植物的幼苗发育。
