Xie Zhongkui

Phenotypic variation of a potential foodcrop, Agriophyllum squarrosum , impacted by environmentalheterogeneity

Agriophyllum squarrosum , also called “sand rice”, is a pioneer annual plant endemic to mobile sand dunes across the temperate deserts of China. It has attracted great interest due to its high agro-ecology value. In this paper, based on a common garden experiment with 26 populations of A. squarrosum , we investigated the relationship between the bio-climatic factors of the original habitat and a couple of important agronomic traits, including Plant height (PH), Seed weight (SW), Stem diameter (STD), Basal branch length (BBL), Aboveground biomass (AGB) and Seed diameter (SED). In general, all the phenotypic traits were significantly related to the latitudinal gradient. Except for SED, all of the traits were higher in the South group than the North group. This result suggested that the South group tends toward vegetative growth, while the North group tends toward reproductive growth. Based on 19 bio-climatic factors from DIVA-GIS, a redundancy analysis with Cannock software showed that the North group was more affected by precipitation, whereas the South group was more affected by temperature. This phenomenon indicates that the natural variations in growth characteristics and energy distribution among the populations of A. squarrosum have been largely impacted by local adaptation and genetic differentiation. Our work supports empirical data for better understanding the ecological genetic basis of how psammophytes adapt to heterogeneous environments and provide important germplasm resources and evaluation methods for the domestication and breeding of A. squarrosum .