Mitochondrial Dna Polymorphism and Gynodioecy in a Natural Population of Rosmarinus Officinalis L.

Abstract

Mitochondrial genome variability was studied in a gynodioecious population of Rosmarinus officina/is L. Analysis of mitochondrial DNA organization using Southem hybridization with probes for mitochondrial genes coxll, cob, and atpA revealed a high level of mitochondrial polymorphism; 11 mitotypes were detected in a total of 27 individuals studied. One mitotype was particularly common among male fertile individuals. The remaining mitotypes were found in only one or two individuals, generally male sterile. Polymorphism was thus greater in male sterile than in male fertile individuals. The data presented here suggest that male sterility in Rosmarinus is associated with the appearance of mitochondrial genome variants which differ from the standard pattern for male fertile plants.

Ecological and historical determinants of population genetic structure and diversity in the Mediterranean shrubRosmarinus officinalis(Lamiaceae)

“…The eventual occurrence of gynodioecy in R. officinalis has been proposed as a mechanism to prevent selfing. However, the genetic determination of gynodioecy in R. officinalis is unclear and may include at least the implication of mitochondrial genes and environmental variables, as the proportion of gynodioecious versus hermaphrodite flowers in R. officinalis varies between individuals and time (Ubera‐Jiménez & Hidalgo‐Fernández, ; Hidalgo‐Fernández et al ., ; personal observation of the authors). This will not completely exclude geitonogamy or biparental inbreeding and thus cannot be considered a major driver of within‐population genetic diversity levels.…”

Seed germination and seedling allogamy inRosmarinus officinalis: the costs of inbreeding

“…Within individual instability in male-sterility may be the result of geneticallycontrolled gender variation in interaction with the environment (Wolfe & Shmida 1997;McCauley& Bailey 2009;Harkess & Leebens-Mack 2016). On the one hand, Hidalgo-Fernández et al (1999) found that rosemary plants with some proportion of male-sterile flowers had higher mitochondrial genome variability than plants with all flowers hermaphrodite, suggesting some kind of genetic control as occurs in other Lamiaceae (Belhassen et al 1991). But on the other hand, the strong and persistent negative effect of altitude on the proportion of male-sterile flowers we found in our study is coherent with the finding that warmer temperatures favour the expression of female flowers (Koelewijn & Van Damm 1996), and point more towards an abnormal development of flowers (Richards 1997, pp.…”