Qu Luping, Widrlechner Mark P
USDA-ARS, North Central Regional Plant Introduction Station, G212 Agronomy Hall, Iowa State University, Ames, IA 50011-1170.
HortScience. 2011 May;46(5):688-692.
Prunella vulgaris (Lamiaceae), commonly known as selfheal, is a perennial herb with a long history of use in traditional medicine. Recent studies have found that P. vulgaris possesses anti-inflammatory, antiviral, and antibacterial properties, and it is likely that this will lead to increased commercial demand for this species. To date, research publications on P. vulgaris cultivation and genetics are scarce. Using accessions originally collected from different geographical regions, we investigated the breeding system of this species by observing variation in floral morphology, time of pollen release, and selfed-seed set in bagged flowers and isolated plants. Two types of floral morphology, one with exerted styles, extending past open corollas when viewed from above, and the other with shorter, inserted styles, were found among 30 accessions. Two accessions originally collected from Asia uniformly displayed exerted styles, and 27 accessions had inserted styles. One accession from Oregon displayed variation in this trait among individual plants. Microscopic observation of seven accessions, including ones with both exerted and inserted styles, revealed that they all release pollen to some degree before the flowers open. Using bagged flowers, we found that selfed-seed set varied widely among eight accessions, ranging from 6% to 94%. However, bagging may underestimate seed set for some accessions. The two accessions with the lowest rates when using bagged flowers increased in seed set by 350% and 158%, respectively, when we evaluated single, unbagged plants in isolation cages. The accession with 6% selfed-seed set when bagged also had exerted styles. These findings suggest that mating systems in P. vulgaris may be in the process of evolutionary change and that understanding breeding-system variation should be useful in developing efficient seed-regeneration protocols and breeding and selection strategies for this species.
夏枯草（唇形科），俗称夏枯草，是一种多年生草本植物，在传统医学中有着悠久的使用历史。最近的研究发现，夏枯草具有抗炎、抗病毒和抗菌特性，这可能会导致对该物种的商业需求增加。迄今为止，关于夏枯草栽培和遗传学的研究出版物很少。我们使用最初从不同地理区域收集的种质，通过观察花形态的变化、花粉释放时间以及套袋花和隔离植株中的自交种子结实情况，对该物种的繁育系统进行了研究。在30份种质中发现了两种花形态，一种是花柱伸出型，从上方看时花柱伸出开放的花冠；另一种是花柱较短、内藏型。最初从亚洲收集的两份种质均表现为花柱伸出型，27份种质具有内藏型花柱。一份来自俄勒冈州的种质在单株植物中表现出该性状的变异。对包括花柱伸出型和内藏型的7份种质进行显微镜观察发现，它们在花开放前都有一定程度的花粉释放。通过套袋花，我们发现8份种质的自交种子结实率差异很大，从6%到94%不等。然而，套袋可能会低估某些种质的结实率。当我们在隔离笼中评估单株未套袋植株时，套袋时结实率最低的两份种质的结实率分别提高了350%和158%。套袋时自交种子结实率为6%的种质也具有花柱伸出型。这些发现表明，夏枯草的交配系统可能正在经历进化变化，了解繁育系统变异对于制定该物种高效的种子繁殖方案以及育种和选择策略可能会有所帮助。
