Floral phenology affects mating system and gene flow of chestnut. A deep knowledge of flowering phenology in natural populations is crucial to assess the phenotypic variation and to predict the adaptive potential of a species facing global climate warming. Comparative studies on flowering time have been carried out on chestnut cultivars but few information is available about natural populations. Furthermore, the existing literature describes this trait in terms of broad qualitative categories (early/late). In this study flowering phenology of Castanea sativaMill. (chestnut) has been investigated in a common garden germplasm collection, including seedlings from several Turkish natural populations. Previous studies highlighted consistent patterns of genetic and climatic variation between Eastern and Western Turkish chestnut populations. Two highly divergent populations, Bursa and Hopa, were selected for this study. Developmental phases of male and female flowers were scored along the entire blooming period in 20-year-old trees. A protocol was set up to quantitatively describe the phenology of flowering in each individual tree. Trees from Bursa flowered slightly later than Hopa trees, however the variation within the populations was much larger than between them. Interestingly, the parents of a full sib family studied for QTL mapping of bud burst, were included in this experiment and showed a different timing of flowering. This opens perspectives for QTL studies on flowering phenology. This study provides a preliminary survey of flowering time variation in natural populations of chestnut and a detailed protocol, which represent a baseline for further studies of gene flow and quantitative genetics in chestnut.
Comparative study of flowering phenology in Castanea sativa natural populations from Turkey
Isacco Beritognolo;Claudia Mattioni;Marcello Cherubini;Fiorella Villani
2012
Abstract
Floral phenology affects mating system and gene flow of chestnut. A deep knowledge of flowering phenology in natural populations is crucial to assess the phenotypic variation and to predict the adaptive potential of a species facing global climate warming. Comparative studies on flowering time have been carried out on chestnut cultivars but few information is available about natural populations. Furthermore, the existing literature describes this trait in terms of broad qualitative categories (early/late). In this study flowering phenology of Castanea sativaMill. (chestnut) has been investigated in a common garden germplasm collection, including seedlings from several Turkish natural populations. Previous studies highlighted consistent patterns of genetic and climatic variation between Eastern and Western Turkish chestnut populations. Two highly divergent populations, Bursa and Hopa, were selected for this study. Developmental phases of male and female flowers were scored along the entire blooming period in 20-year-old trees. A protocol was set up to quantitatively describe the phenology of flowering in each individual tree. Trees from Bursa flowered slightly later than Hopa trees, however the variation within the populations was much larger than between them. Interestingly, the parents of a full sib family studied for QTL mapping of bud burst, were included in this experiment and showed a different timing of flowering. This opens perspectives for QTL studies on flowering phenology. This study provides a preliminary survey of flowering time variation in natural populations of chestnut and a detailed protocol, which represent a baseline for further studies of gene flow and quantitative genetics in chestnut.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
