The present study was to identify the communities of B. tournefortii Gouan in Al-Jouf areas in northern Saudi Arabia, to determine soil factors controlling its genetic variability and its allelopathic control. The plant communities dominated by B. tournefortii were investigated in fifteen localities. A collection of fifteen Saudi Arabian B. tournefortii populations was evaluated using five morphological traits. Analysis of variance and correlation coefficient were performed based on R software package. Soils representing each community were analyzed using eleven physico-chemical parameters. The allelopathic effects of Portulaca oleracea and Pulicaria undulata and their mixtures on germination, seedling root and shoot growth of B. tournefortii were investigated. The dendrogram based on trait variation using UPGMA method, shows genetic difference between the studied populations. Genetic variability analysis showed a important variability of number of seeds per plant (cv = 19.522) and number of pods per plant (cv = 11.663). The water extracts of Portulaca oleracea and Pulicaria undulata could be applied at a concentration of 10 g/L for the management of this species.

中文翻译：

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土壤化感特性对沙特阿拉伯北部不同种群白菜遗传、生理和形态参数的影响

本研究旨在确定沙特阿拉伯北部 Al-Jouf 地区的 B. tournefortii Gouan 群落，以确定控制其遗传变异和化感控制的土壤因素。在十五个地点调查了以 B. tournefortii 为主的植物群落。使用五种形态特征评估了 15 个沙特阿拉伯 B. tournefortii 种群的集合。基于R软件包进行方差和相关系数分析。使用十一种物理化学参数分析代表每个群落的土壤。研究了马齿苋和蒲公英及其混合物对马齿苋萌发、幼苗根和芽生长的化感作用。使用UPGMA方法基于性状变异的树状图，显示了研究群体之间的遗传差异。遗传变异分析显示每株植物的种子数 (cv = 19.522) 和每株植物的豆荚数 (cv = 11.663) 存在重要变异。马齿苋和蒲公英的水提取物可以以 10 g/L 的浓度施用来管理该物种。