# Local Adaptation Shapes Phenotypic and Genetic Diversity in Zygophyllum loczyi

## TL;DR

This study explores how Zygophyllum loczyi adapts to harsh desert environments by examining its phenotypic and genetic diversity across different populations.

## Contribution

The study provides new insights into the local adaptation mechanisms of Z. loczyi through inter-population phenotypic and genetic analysis.

## Key findings

- Z. loczyi shows significant inter-population phenotypic differentiation, with more variation between deserts than within them.
- Environmental factors like temperature and moisture strongly influence traits such as blade and petal length in Z. loczyi.
- The Gurbantunggut desert population shows the highest selection pressure and smallest effective population size.

## Abstract

Background/Objectives: Desert plants exhibit remarkable resilience to extreme environments, and their capacity for population establishment is noteworthy. However, the adaptation process mechanisms of those plants to harsh habitats, particularly concerning intraspecific differentiation and genetic diversity, remain poorly understood, and a comprehensive framework is lacking. Zygophyllum loczyi Kanitz, an annual or biennial desert herb, demonstrates significant phenotypic plasticity across diverse habitats. Methods: Using mixed-effects models, this study examined 20 populations from four deserts to assess phenotypic variation and predict trait_environment relationships. Results: The findings indicated substantial inter-population phenotypic differentiation in Z. loczyi, with greater variation observed between deserts than within them. Traits such as blade length, petal length, sepal length, and stamen length were influenced by environmental conditions. Mixed-effects model prediction showed that the growth location of Z. loczyi significantly impacted its phenotypic traits. The characteristics of the four desert populations displayed varying responses to temperature and moisture changes, with the most pronounced response noted in the Gurbantunggut desert (Gt) population, indicating that survival stress has an important influence on the performance of plants. The single nucleotide polymorphisms result further confirmed that the differentiation and genetic diversity of the Gt population displayed the highest selection pressure, resulting the small effective size of the population. Conclusions: This study uncovers the adaptive mechanism of Z. loczyi to habitat through investigating the inter-population phenotypic differentiation and genetic diversity and provides new insight into local adaptation and evolutionary processes in the desert environment.