Quantitative evaluation of the petal shape variation in Primula sieboldii caused by breeding process in the last 300 years

Abstract

Primula sieboldii (E. Morren) has been a popular garden plant at least since the Edo period, about 300 years ago. We compared petal form between cultivars and wild populations in order to characterise the changes that have occurred during domestication. The comparison was made using EF-PCA analysis, which describes overall petal shape mathematically by transforming petal contour coordinates into elliptic Fourier descriptors; it subsequently summarises these descriptors by principal component analysis (PCA). Rearing cultivars in a common-garden experiment identified the PCs with a substantial genetic element. A clear heritable component was detected for the PCs characterising symmetrical variation in flower shape, but not the asymmetrical variation. Wild populations of this species have become endangered owing to habitat destruction by human activity, and many lowland floodplain habitats have been lost. Variation within the remaining wild populations was significantly lower than in the cultivars for PC1 (aspect ratio), PC3 (curvature of proximal and distal parts) and petal area; but not for PC2 (depth of head notch) and PC4 (position of the centre of gravity). The shifts in petal form from the wild populations to the cultivars parallel those seen in other croptypes following domestication, including an increase in size and diversity of forms: cultivars have shallower head notches, more fan-shaped petals and larger petals than do wild P. sieboldii. Heredity (2005) 94, 657-663.

Evolution through genetically controlled allometry space

“…Such a framework should incorporate allometric relationships, as changes in size are often accompanied by changes in shape (1), reflecting an interaction between developmental and selective constraints. Much progress has been made in quantifying shape or size variation between species, ecotypes, and varieties by using numerical methods (2)(3)(4)(5)(6), and in some cases genes underlying this variation have been defined by QTL analysis (7)(8)(9). However, so far, these approaches have not been combined to allow variation between a range of species to be placed in a genetic context.…”

The role of crop-pollinator relationships in breeding for pollinator-friendly legumes: from a breeding perspective

“…For instance, floral organs can be photographed or scanned and their size and shape analyzed by using various image software packages. DIAS of traits, such as standard length, width, area, and perimeter, facilitates extensive and detailed phenotypic analyses to describe subtle differences in flower size (Yoshioka et al 2004(Yoshioka et al , 2005. Appropriate software packages can provide more accurate, consistent, and objective measurement for floral traits, such as style length, ovary style angle (for assessment of the mechanical fit to pollinator) or pollen presentation that were impossible or impractical to determine manually (Suso et al 2005a).…”

Genetic variation and differentiation of floral morphology in wild Primula sieboldii evaluated by image analysis data and SSR markers

“…Our results also suggested that other cultivars originated from the wide floral variation in the Saitama population. With regard to genetic variation in the depth of the head notch (PC1), Yoshioka et al (2005) showed that wild P. sieboldii had a deeper head notch than cultivars; the shallower head notch may have resulted from previous breeding manipulations, such as crossing and selection. Currently, none of the more than 300 P. sieboldii cultivars have a deep head notch.…”