Scotia Seeds, Brechin, UK.
Dipartimento di Scienze della Terra e dell'Ambiente, Università di Pavia, Pavia, Italy.
Plant Biol (Stuttg). 2019 May;21(3):470-479. doi: 10.1111/plb.12707. Epub 2018 Mar 8.
The facultative root hemi-parasite Rhinanthus minor is often used in grassland habitat restoration projects to regulate ecosystem structure and function. Its impact on community productivity and diversity as a function of resource supply, sward composition and management has been widely investigated. However, there is a lack of information about the possible influence of seed quality on the efficacy of the hemi-parasite. Ten seed lots from commercial sources were sown in the field and their germination characteristics investigated in the laboratory. Seeds from four lots were also germinated and sown in pots alongside plants of two host species, Lotus corniculatus and Holcus lanatus. Plant establishment, height and flowering density were evaluated for the hemi-parasite, while plant biomass was measured for both R. minor and its host. Two aspects of seed quality influenced the field emergence of seed lots of R. minor, the radicle emergence (%) and the length of the lag period from the beginning of imbibition to germination (mean germination time), which indicates seed vigour. A longer lag period (lower vigour) was associated with higher levels of seedling mortality and lower plant vigour, in terms of plant height and biomass accumulation and was also reflected in the parasitic impact of the seed lots. Seed quality, specifically germination and vigour, can influence the establishment, survival, subsequent plant productivity and parasitic impact of R. minor in vegetation restoration projects. Seed quality is discussed as a key factor to consider when predicting the impact of the hemi-parasite on community productivity and diversity.
兼性根半寄生植物米氏列当通常用于草原生境恢复项目中，以调节生态系统的结构和功能。它对群落生产力和多样性的影响作为资源供应、草丛组成和管理的函数已经得到了广泛的研究。然而，关于种子质量对半寄生植物功效的可能影响的信息还很缺乏。从商业来源收集了十个种子批，在田间播种，并在实验室研究了它们的发芽特征。四个种子批的种子也在与两种宿主植物——角果毛茛和黑麦草一起种植的花盆中发芽和播种。对半寄生植物的植物建立、高度和开花密度进行了评估，同时测量了 R. minor 和其宿主的植物生物量。有两个方面的种子质量影响了米氏列当种子批在田间的萌发，胚根萌发（%）和从吸胀开始到萌发的滞后时间（平均发芽时间），这表明了种子活力。较长的滞后时间（较低的活力）与较高的幼苗死亡率和较低的植物活力相关，表现在植物高度和生物量积累方面，也反映在种子批的寄生影响上。种子质量，特别是发芽和活力，可以影响 R. minor 在植被恢复项目中的建立、存活、随后的植物生产力和寄生影响。讨论了种子质量作为预测半寄生植物对群落生产力和多样性影响的关键因素。
