Manuscript Click here to access/download;Manuscript;renamed_e47b4.docx 1 The Mendelian inheritance of gynomonoecy: insights from Anacyclus hybridizing species 2 3 Inés Álvarez1, 3, A. Bruno Agudo1, Alberto Herrero1, and Rubén Torices2 4 5 1 Departamento de Biodiversidad y Conservación, Real Jardín Botánico (RJB), Consejo Superior 6 de Investigaciones Científicas (CSIC), Plaza de Murillo 2, 28014-Madrid, Spain. 7 2Área de Biodiversidad y Conservación, Universidad Rey Juan Carlos, C/ Tulipán s/n, 28933- 8 Móstoles, Madrid, Spain. 9 3For correspondence:
[email protected] 10 11 Manuscript received _____________________; revision accepted _____________________. 12 13 Short title: Gynomonoecy inheritance 1 14 ABSTRACT 15 Premise of the study Gynomonoecy is an infrequent sexual system in 16 Angiosperms, although widely represented within the Asteraceae family. 17 Currently, the hypothesis of two nuclear loci that control gynomonoecy is the most 18 accepted. However, the genic interactions are still uncertain. Anacyclus clavatus, 19 A. homogamos and A. valentinus differ in their sexual system and floral traits. 20 Here, we investigate the inheritance of gynomonoecy in this model system to 21 understand its prevalence in the family. 22 Methods We selected six natural populations (two per species) for intra- and 23 interspecific experimental crosses, and generated a total of 1123 individuals from 24 F1, F2, and backcrosses for sexual system characterization. The frequency of 25 gynomonoecy observed for each cross was tested to fit different possible 26 hypotheses of genic interaction. Additionally, the breeding system and the degree 27 of reproductive isolation between these species were assessed. 28 Key Results Complementary epistasis, in which two dominant alleles are required 29 for trait expression, explained the frequencies of gynomonoecy observed across all 30 generations.