Phenolic compounds are natural phytotoxins which play role as chemical defense compounds in wheat species. However, the contribution and role of phenolic compounds in ancient and modern wheat genotypes for plant-to-plant interference are equivocal. Biological screening of seven wheat genotypes including five emmer wheat genotypes of Triticum turgidum ssp. dicoccum (Zarneh, Singerd, Shahrekord, Khoygan and Joneghan), one modern hexaploid wheat genotype (Triticum aestivum var. Roushan) and one modern tetraploid wheat genotype (Triticum turgidum var. Yavaroos) demonstrated that all wheat genotypes suppressed the seedling growth of Raphanus sativus L. by shoot aqueous extract in a dose–response bioassay. Modern hexaploid wheat genotypes along with ancient tetraploid emmer wheat genotypes possessed a high allelopathic capability. High-performance liquid chromatography diode array detection analysis of aqueous extracts indicated that the ability to synthesise polyphenolic compounds is different among genotypes. The total amount of polyphenolics and flavonoid compounds in shoot aqueous showed a significant correlation to the R. sativus growth suppression. These results suggest that the number of polyphenolics in general and syringic acid in particular may have contributed to the allelopathic effects of ancient tetraploid and modern hexaploid wheat genotypes. At the same time, results showed that ancient tetraploid emmer wheat may offer promising values for their unique composition of allelochemicals, indicating their potential in sustainable crop production systems.

酚类化合物是天然植物毒素，在小麦中起化学防御作用。然而，酚类化合物在古代和现代小麦基因型中对植物间干扰的贡献和作用是模棱两可的。7小麦品种包括5个二粒小麦基因型的生物筛选圆锥小麦SSP。dicoccum（Zarneh，Singerd，Shahrekord，Khoygan和Joneghan），一种现代六倍体小麦基因型（Triticum aestivum var。Roushan）和一种现代四倍体小麦基因型（Triticum turgidum var。Yavaroos）表明，所有小麦基因型均抑制了Raphanus的幼苗生长。  L.通过芽生水提取物进行剂量反应生物测定。现代六倍体小麦基因型与古代四倍体Emmer小麦基因型具有很高的化感能力。水提取物的高效液相色谱二极管阵列检测分析表明，基因型之间合成多酚化合物的能力不同。枝条水溶液中多酚和黄酮类化合物的总量与栽培番茄呈显着相关性。生长抑制。这些结果表明，多酚类化合物的数量，特别是丁香酸的数量，可能与古代四倍体和现代六倍体小麦基因型的化感作用有关。同时，结果表明，古老的四倍体Emmer小麦因其独特的化感物质组成可能具有广阔的价值，表明其在可持续作物生产系统中的潜力。