Mating systems in tropical forages: Stylosanthes capitata Vog. and Stylosanthes guianensis (Aubl.) Sw

• Published in: Euphytica Vol. 178; no. 2; pp. 185 - 193
• Main Authors: Santos-Garcia, Melissa de Oliveira, Resende, Rosângela Maria Simeão, Chiari, Lucimara, Zucchi, Maria Imaculada, de Souza, Anete Pereira
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.03.2011; Springer; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Analysis; Beans; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Classical and quantitative genetics. Population genetics. Molecular genetics; Fundamental and applied biological sciences. Psychology; Generalities. Genetics. Plant material; Genetic markers; Genetics and breeding of economic plants; Inbreeding; Legumes; Life Sciences; Mimosaceae; Molecular genetics; Plant breeding: fundamental aspects and methodology; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant populations; Plant reproduction; Plant Sciences; Selective breeding; Autogamy; Plant breeding; Microsatellite markers; Mixed mating system; Tropical crop; Molecular marker; Mating system; Leguminosae; Dicotyledones; Microsatellite DNA; Angiospermae; Genetic improvement; Spermatophyta; Fodder crop; Microsatellite marker; Combined system
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-010-0293-x

Stylosanthes capitata and S. guianensis are important forage legumes for tropical areas. The only available estimates of S. capitata and S. guianensis outcrossing rates were based on morphological markers, and the genus is considered as being mainly self-pollinated. Here we describe an estimation of the outcrossing rate in S. capitata and S. guianensis using microsatellite markers. The outcrossing rates were estimated in S. capitata and S. guianensis open-pollinated populations of 20 progenies consisting of ten individuals each. The multi locus outcrossing rate for S. capitata was estimated using 10 polymorphic loci, whereas five microsatellites were used for S. guianensis. The multi locus outcrossing rates for S. capitata and S. guianensis were 31 and 26%, respectively, suggesting a mixed mating system with predominance of autogamy. Comparison of single locus and multi locus estimates of outcrossing rates indicated that little inbreeding other than selfing occurred. The estimated Wright’s fixation index of the parental generation was lower than expected based on the multi locus outcrossing rate, possibly resulting from the use of some heterozygous breeding genotypes for the study. The data on the outcrossing rate described here are potentially useful for breeding programs and for maintenance of germplasm collections of these Stylosanthes species.