Effects of ploidy level and haplotype on variation of photosynthetic traits: Novel evidence from two Fragaria species

Abstract

To reveal the effects of ploidy level and haplotype on photosynthetic traits, we chose 175 genotypes of wild strawberries belonging to two haplotypes at two types of ploidy levels (diploidy and tetraploidy) and measured photosynthetic traits. Our results revealed that ploidy significantly affected the characteristics of light-response curves, CO2-response curves, and leaf gas exchange parameters, except intercellular CO2 concentration (Ci). Tetraploid species had a lower light saturation point (LSP) and CO2 saturation point (CSP), higher light compensation point (LCP), dark respiration (Rd), and CO2 compensation point (CCP) than diploid species. Furthermore, tetraploid species have lower photosynthetic capacity than diploid species, including net photosynthetic rate (Pn), stomatal conductivity (Gs), and transpiration rate (Tr). In addition, haplotype had a significant effect on LSP, CSP, Tr, and Ci as well as a significant interactive effect between ploidy and haplotype on the maximal photosynethic rate of the light-response curve and Rd. Most of the variance existed within haplotypes among individuals. These results suggest that polyploidization was the main driver for the evolution of photosynthesis with increasing ploidy level (i.e. from diploidy to tetraploidy in Fragaria species), while the origin of a chromosome could also affect the photosynthetic traits and the polyploidization effect on photosynthetic traits.

Synthetic Polyploidy in Grafted Crops

“…It has been showed that stomata closure can depend on leaf ABA, even though rootstock may contribute to the production of ABA ( McAdam et al, 2016 ). Polyploidy can lower the gas exchange capacity as seen in 4x strawberries ( Fragaria moupinensis Cardot; Gao et al, 2017 ). In this sense, the stomata closure regulatory mechanism, led by root-to-shoot signaling that is triggered by drought and mediated by the plant hormone ABA ( Schachtman and Goodger, 2008 ) is said to be altered by polyploidy.…”

Comparative Analysis of Morphology, Photosynthetic Physiology, and Transcriptome Between Diploid and Tetraploid Barley Derived From Microspore Culture

“…However, in comparison with diploids, the changed photosynthetic rate in polyploids differs according to the species studied. For example, it is higher in Allium oleraceum ( Eliška et al, 2015 ), Phlox drummondii ( Vyas et al, 2007 ), Malus × domestica ( Xue et al, 2017 ), and Lilium ( Cao et al, 2018 ), but lower in Triticum ( Hejnák et al, 2016 ) and Fragaria ( Gao et al, 2017 ), yet moderate in Hordeum vulgare ( Sicher et al, 1984 ).…”

Interspecific and intraspecific phenotypic diversity for drought adaptation in bioenergy Arundo species

“…However, this prediction is not verified in Arundo, where A. plinii showed higher g s and A sat than A. donax and A. donaciformis. This is possibly due to the fact that physiological consequences of polyploidy seem to be largely taxon-specific, with variable outcomes depending on the relative ratio between photosynthetic rates and number of cells per unit leaf area (Gao et al, 2017;Greer et al, 2018;Vyas et al, 2007;Warner & Edwards, 1993).…”