The biosynthesis and accumulation of secondary metabolites in plant tissues interact strongly with environmental conditions and breeding systems. Limited knowledge is available on the effects of breeding system (self vs. open pollination) and deficit irrigation on the composition of flavonolignans, seed yield, and oil content of different genotypes of milk thistle (Silybum marianum L.). Four ecotypes of Iranian milk thistle collected from diverse geographical regions were each self- and open-pollinated; they were then assessed in the field under both normal and deficit irrigation for seed yield, oil percentage, silymarin, and its components during 2014 and 2015. Deficit irrigation decreased seed yield and silybin A but increased total silymarin content, silybin B, and silydianin. In both moisture environments, seed yield was positively associated with oil percentage and silybin A. Open pollination improved seed yield, oil percentage, total silymarin, and its components in milk thistle ecotypes as compared with self-pollination. Considerable genetic variability was observed among the evaluated ecotypes in their response to moisture environments and pollination status. Under open pollination, the northern Iranian ecotypes Mashhad and Sari were identified as promising varieties for further studies.

中文翻译：

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授粉系统和亏缺灌溉影响水飞蓟素的黄酮木脂素成分、油和奶蓟的生产力

植物组织中次生代谢物的生物合成和积累与环境条件和育种系统密切相关。关于育种系统（自花授粉与开放授粉）和亏缺灌溉对不同基因型奶蓟 ( Silybum marianum)黄酮木脂素组成、种子产量和油含量的影响的知识有限L.）。从不同地理区域收集的四种伊朗奶蓟生态型分别是自花授粉和开放授粉的；然后，在 2014 年和 2015 年期间，在正常灌溉和亏缺灌溉下的田间对种子产量、含油率、水飞蓟素及其成分进行了评估。亏缺灌溉降低了种子产量和水飞蓟素 A，但增加了总水飞蓟素含量、水飞蓟素 B 和水飞蓟素。在这两种潮湿环境中，种子产量与油百分比和水飞蓟宾 A 呈正相关。与自花授粉相比，开放授粉提高了奶蓟生态型的种子产量、油百分比、总水飞蓟素及其成分。在评估的生态型中观察到相当大的遗传变异性，以反映它们对水分环境和授粉状态的反应。在开放授粉下，