Phenotypic Variation in Leaf, Fruit and Seed Traits in Natural Populations of Eucommia ulmoides, a Relict Chinese Endemic Tree

Abstract

Eucommia ulmoides Oliver is a dioecious, pharmaceutically and economically important, and precious relict tree species endemic to China, and has been listed as a key protected tree species of national level II. Phenotypic variation in ten natural populations in some key traits is still obscure. In order to study the relationship between population variation in phenotypic traits and geoclimatic factors, 15 traits were analyzed in 117 female sampled tree from ten natural populations. The results showed that the coefficients of variation for all of the 15 traits widely ranged from 9.7% (fruit vertical diameter) to 49.0% (leaf thickness), with an average of 19.7%. The nested ANOVA revealed plentiful phenotypic variations within and among populations. The variation within population was the main source, with an average proportion of 42.8%, greater than that among the population (16.6%). The 15 traits were reduced to four principal components, which collectively accounted for 70.1% of phenotypic variation among trees. The ten populations were mainly divided into two groups: Group A included eight populations throughout the Wuling Mountains occurring in relatively close proximity to each other, and Group B which comprises two geographically distant populations in mountains further northern. There were significant level correlations between phenotypic differentiation among population of E. ulmoides and both geographic (r = 0.65, p < 0.05) and climatic (r = 0.73, p < 0.01) distance. Step-wise regression indicates average annual temperature and rainfall accounted for most of the phenotypic variation among populations, and mainly associated with differences in leaf, fruit and seed size. These results can have an important implication for genetic improvement, diversity conservation and resource management of the species in the future.

Patterns of Leaf and Fruit Morphological Variation in Marginal Populations of Acer tataricum L. subsp. tataricum

“…Similar results were reported for Eucommia ulmoides Oliv. [ 51 ] and Malania oleifera Chun and S.K. Lee [ 52 ].…”

Estimation of morphological variation in seed traits of Sophora moorcroftiana using digital image analysis

“…The relatively high genotypic variation in these traits indicated potential genetic variation among the 15 S. moorcroftiana accessions that could be used for selection and breeding ( Dong et al., 2019 ). Furthermore, these seed trait variation reflects the result of genetic variation and phenotypic plasticity in response to environmental variation ( Wang et al., 2023 ). This information helps to understand the response mechanism and variation rules of plants to the environment, which is important for the collection, preservation and evaluation of germplasm resources.…”

Phenotypic Diversity Analysis in Elaeagnus angustifolia Populations in Gansu Province, China

“…t/s is the variance component among populations, and σ 2 s is the variance component within the population (family) [27,29].…”

“…From long-term field observations, we found that E. angustifolia in Gansu Province has formed a rich resource diversity under a complex geography, climate, and long cultivation history, and different regions have significant phenotypic differences. Therefore, some reasons for the phenotypic diversity of E. angustifolia can be explained by exploring its phenotypic variation, so as to understand the response of E. angustifolia growth to the ecological environment and also provide some basis for the genetic improvement, diversity conservation, and resource management of E. angustifolia [27].…”