Variations in morphological traits of bermudagrass and relationship with soil and climate along latitudinal gradients

Abstract

BackgroundThis complex environmental heterogeneity coupled with the long-standing history offers scenario suitable for and favoring the evolution and existence of variation of morphological traits.MethodsIn this study, we measured 10 morphological traits of 310 Cynodon dactylon individuals sampled at 16 different locations along latitudinal gradients between 22°35′N and 36°18′N to reveal phenotypic plasticity influenced by latitude. In addition, the relationships between morphological variation and soil nutrient and climate factors were analyzed.ResultsAnalysis of variance, divesity examination and Mantel correlation test detected a significant effect of latitude on morphological traits. Cluster analysis and principal component analysis clearly separated the selected populations into four groups according to latitude. Larger morphological sizes of C. dactylon appeared at the low- and high-latitude regions. Correlation analysis indicated that high morphological variations were significantly correlated with climate factors and soil nutrient.ConclusionThis study suggests morphological variation of wild bermudagrass is greatly influenced by latitude as well as soil and climate, which could be useful resources for genetic studies and evolution.

Morphological variation in Cynodon dactylon (L.) Pers., and its relationship with the environment along a longitudinal gradient

“…Bermudagrass is a widespread species that is adaptable to adverse environments that shows a contrary strategy in morphological traits to adapt to dry and low temperature conditions. However, high temperatures did not cause increases in plant size along a latitudinal gradient in another study [31].…”

“…Morphological variation as a response to environmental changes at different geographic positions is common in C. dactylon [38,39]. A study of 260 accessions of bermudagrass germplasm indicated that there is extensive morphological variation in C. dactylon populations along longitudinal gradients, which has been found in some other studies [31,40,41]. The correlation analysis showed that the traits of width and dimeter were seldom significantly correlated with the longitude, soil nuriture or climate.…”

“…The morphological characters, including leaf length of the erect shoot (LLES), leaf width of the erect shoot (LWES), internode length of the erect shoot (ILES), diameter of the erect shoot (DES), leaf length of the stolon (LLS), leaf width of the stolon (LWS), internode length of the stolon (ILS), diameter of the stolon (DS), plant height (PHT), and reproductive branch height (RBH) were measured for 20 individual plants per site. The sampling method was as described in our previous study [31]. The samples were measured with the aid of a caliper during the highest growth period in August.…”

“…In our study, longer internodes were found in those areas with lower MAR and MAT. Previous studies showed that internode length in bermudagrass is significantly and negatively related to rainfall and temperature [31]. In areas with low rainfall and low temperatures, one adaptation mechanism for drought could be an increase in the internode length that would allow the leaf to more effectively absorb resources.…”

Non-linear genetic diversity and notable population differentiation caused by low gene flow of bermudagrass [Cynodon dactylon(L.) Pers.] along longitude gradients

“…C. dactylon is an enormously variable and cosmopolitan warm-season turfgrass used for lawns, parks, and sports fields (Shi, Ye & Chan, 2013), which justifies new and innovative approaches toward evaluating and understanding the genetic relationships among different populations at different longitudes. Some studies have been used to analyze genetic diversity and population structure of bermudagrass because of its efficient dispersal and establishment abilities, rapid population growth, and phenotypic plasticity (Linder et al, 2018;Zheng et al, 2017;Zhang et al, 2018). Identifying the correlation between simple sequence repeat (SSR) markers and turf-quality-related traits among different bermudagrass populations can efficiently help to select high turf quality for bermudagrass.…”