Sorgoleone-358 is an important allelochemical of the oily droplets exuded from root hairs of various species in the Sorghum genus. Due to its hydrophobic nature, sorgoleone-358 can be strongly adsorbed onto soil organic matter, resulting in increased sorgoleone soil persistence. Because of the herbicidal activity of sorgoleone on many small-seeded weeds, concerns have been raised that sorghum residues may have a detrimental effect on emergence of wheat used as a double crop in the southeastern United States. Laboratory experiments were conducted to evaluate root exudate production and its sorgoleone-358 content for 36 cultivated sorghum cultivars as well as eight shattercane [Sorghum bicolor (L.) Moench ssp. arundinaceum (Desv.) de Wet & Harlan] accessions and one johnsongrass [S. halepense (L.) Pers.] accession. Using a capillary growing mat system, root exudate was extracted with dichloromethane and subjected to chromatography analysis to determine sorgoleone-358 content. Root biomass of 7- to 12-d-old seedlings averaged 18.8 mg g-1 seed, and root exudate production ranged from 0.2 and 4.8 mg g-1 root fresh weight (RFW). The amount of sorgoleone produced varied greatly among sorghum accessions. Sorgoleone-358 amount in the root exudate averaged 0.5 mg g-1 RFW and varied from 0.13 to 1.05 mg g-1 for shattercane cultivar S7 and cultivated sorghum cultivar 992123, respectively. Regarding volume of root biomass, sorgoleone-358 levels averaged 0.49 mg g-1 (range, 0.06-1.46 mg g-1 ) for sorghum cultivar AAS3479 and shattercane cultivar S2, respectively. Segregation of commercial sorghum cultivars according to their maturity group did not show any difference in root biomass and dry extract production, but early-maturing cultivars produced on average 18% less sorgoleone-358 compared with medium- and late-maturing cultivars. These results suggest that sorgoleone production may be genetically constitutive because sorghum growing conditions were identical across cultivars.

中文翻译：

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高粱物种 sorgoleone 生产的保护和分化

Sorgoleone-358 是高粱属不同物种根毛渗出的油性液滴的重要化感化学物质。由于其疏水性，sorgoleone-358 可以强烈吸附到土壤有机质上，从而增加土壤中的 sorgoleone 持久性。由于 sorgoleone 对许多小种子杂草的除草活性，有人担心高粱残留可能对美国东南部用作双季作物的小麦的出苗产生不利影响。进行了实验室实验以评估 36 个栽培高粱品种和 8 个碎茎 [Sorghum bicolor (L.) Moench ssp. 的根系分泌物产生及其 sorgoleone-358 含量。arundinaceum (Desv.) de Wet & Harlan] 种质和一个 johnsongrass [S. halepense (L.) Pers.] 加入。使用毛细管生长垫系统，用二氯甲烷提取根系分泌物并进行色谱分析以确定 sorgoleone-358 含量。7 至 12 天龄幼苗的根生物量平均为 18.8 mg g-1 种子，根系分泌物产量介于 0.2 和 4.8 mg g-1 根鲜重 (RFW) 之间。高粱种质之间产生的高岭土的量差异很大。根系分泌物中的 Sorgoleone-358 含量平均为 0.5 mg g-1 RFW，对于 shattercane 品种 S7 和栽培高粱品种 992123，分别为 0.13 至 1.05 mg g-1。关于根生物量的体积，高粱栽培品种 AAS3479 和碎茎栽培品种 S2 的 sorgoleone-358 水平分别平均为 0.49 mg g-1（范围，0.06-1.46 mg g-1）。根据成熟组对商业高粱品种的分离在根生物量和干提取物产量方面没有显示出任何差异，但与中熟和晚熟品种相比，早熟品种生产的 sorgoleone-358 平均少 18%。这些结果表明，高粱的生产可能是遗传组成的，因为高粱的生长条件在不同品种之间是相同的。