Population dynamics of Agriophyllum squarrosum, a pioneer annual plant endemic to mobile sand dunes, in response to global climate change

Abstract

Climate change plays an important role in the transition of ecosystems. Stratigraphic investigations have suggested that the Asian interior experienced frequent transitions between grassland and desert ecosystems as a consequence of global climate change. Using maternally and bi-parentally inherited markers, we investigated the population dynamics of Agriophyllum squarrosum (Chenopodiaceae), an annual pioneer plant endemic to mobile sand dunes. Phylogeographic analysis revealed that A. squarrosum could originate from Gurbantunggut desert since ~1.6 Ma, and subsequently underwent three waves of colonisation into other deserts and sandy lands corresponding to several glaciations. The rapid population expansion and distribution range shifts of A. squarrosum from monsoonal climate zones suggested that the development of the monsoonal climate significantly enhanced the population growth and gene flow of A. squarrosum. These data also suggested that desertification of the fragile grassland ecosystems in the Qinghai-Tibetan Plateau was more ancient than previously suggested and will be aggravated under global warming in the future. This study provides new molecular phylogeographic insights into how pioneer annual plant species in desert ecosystems respond to global climate change, and facilitates evaluation of the ecological potential and genetic resources of future crops for non-arable dry lands to mitigate climate change.

SNP Discovery and Genetic Variation of Candidate Genes Relevant to Heat Tolerance and Agronomic Traits in Natural Populations of Sand Rice (Agriophyllum squarrosum)

“…A total of 60 individuals from 10 natural populations (FK, DH, QHH, YJ, M4, MQ, SPT, JB, DLSH, NM) as described in Qian et al (2016) were used to determine the genetic diversity of the three candidate genes ( HsfA1d, DAR1, LHY , and ELF3 ). Samples from two individual plants from the SPT and NM populations were first amplified and sequenced in both directions to confirm the suitability of primers for population sequencing.…”

“…Sand rice originates from the Gurbantunggut desert and is widely distributed on the mobile and semi-mobile sand dunes across the arid regions of northern China (Zhao et al, 2014; Qian et al, 2016). To thrive in a desert environment, sand rice has evolved many morphological traits and adaptation strategies to mitigate the risk of extinction due to climate variability, such as extreme temperatures, unpredictable precipitation, strong solar radiation, and other environmental stresses (Chen et al, 2014; Zhao et al, 2014).…”

“…The climate varies considerably across the geographic range of sand rice, and precipitation and mean temperature of the coldest quarter strongly influence its distribution (Qian et al, 2016). Furthermore, phenology variation has been observed among natural populations of sand rice (Zhao et al, 2014; Yin et al, 2016); for example, the seed size from semi-arid region (Naiman, NM) is larger than that from arid region [Shapotou (SPT); Figure 1 ].…”

“…In this study, two representative sand rice plants from arid and semi-arid regions (SPT and NM) were sequenced using the RNA-seq method to generate a genome wide dataset of SNP polymorphisms. Four candidate genes, HsfA1d, DAR1, LHY , and ELF3 , were selected for further assessment of allelic diversity in 10 natural populations, which represent the core germplasm resources of sand rice, according to the results of phylogeographic analysis (Qian et al, 2016). …”

Ecophysiological Responses of Three Tree Species to a High-Altitude Environment in the Southeastern Tibetan Plateau

“…Climate change affects the distribution, population structure, and growth dynamics of plants [1,2]. Survival of a species in a particular environment requires the ability to adapt to the habitat's characteristics, and, plants have developed a wide range of physiological responses to cope with environmental stresses [3].…”