Genetic structure of needle morphological and anatomical traits of Pinus yunnanensis

Abstract

Pinus yunnanensis Franch. is an particular conifer tree species in Yunnan-Guizhou plateau in southwest China. The morphological and anatomical traits of needles are important to evaluate geographic variation and population dynamics of conifer species. Seedlings from seven populations of P. yunnanensis were analyzed, looking at 22 morphological and anatomical needle traits. The results showed that variations among and within populations were significantly different for all traits and the variance components within populations were generally higher than that among populations in the most tested needle traits. The proportions of three-needle fascicle were significantly different among populations. The traits related to needle size in both morphology and anatomy were positive with latitude and negative with annual temperature and precipitation. Ratio indices, including mesophyll area/vascular bundle area, mesophyll area/resin canals area, vascular bundle area/resin canals area and mesophyll area/(resin canals area and vascular bundle area), were negatively correlated with elevation and positively correlated with the annual mean temperature, showing some fitness feature for the populations. Needle traits were more significantly correlated with longitude than with other four environmental factors. Needle length was significantly correlated with almost all environmental factors. First four principal components accounted for 81.596 % of the variation with eigenvalues [1; the differences among populations were mainly dependent on needle width, stomatal density, section areas of vascular bundle, total resin canals, and mesophyll, as well as area ratio traits. Seven populations were divided into three categories by Euclidean distance. Variations in needle traits among the populations have shown systematic microevolution in terms of geographic impact on P. yunnanensis. This study would provide empirical data to characterize adaptation and genetic variation of P. yunnanensis, which would be helpful for management of genetic resources and reasonable utilization of them in future.

Genetic Analysis of Needle Morphological and Anatomical Traits among Nature Populations of Pinus Tabuliformis

“…We examined a total of 20 traits involving morphology, anatomy and ratio of needle structures (Table 2). All the traits were adaptive-related and have been reported in previous researches (Huang et al, 2016;Xing et al, 2014;Zhao et al, 2008).…”

“…Needle is the most vigorous assimilation organs for conifer species, and the morphological and anatomical traits of needle are important references to plant taxonomy (Anna K. et al, 2013;Xing, 2014;Huang, 2016). Needle traits are closely associated with physiological and functional attributes of plants including photosynthesis, respiration, water metabolism, nutritional status, as well as stress resistance (Oleksyn et al, 1997;Eguchi et al, 2004;Wu, 2007;Mao et al, 2012).…”

Cold adaptation drives variability in needle structure and anatomy in Pinus sylvestris L. along a 1,900 km temperate–boreal transect

“…The decrease of needle length with decreasing T min is consistent with latitudinal trends in other boreal vs. temperate populations of conifers (Mamayev, ; Nobis, Traiser, & Roth‐Nebelsick, ; Reich et al., ). Needle length reduction may indicate growth‐limiting conditions (Junttila & Heide, ; Norgren & Elfving, ); however, the relationship between needle length and habitat temperature does have a genetic component, suggesting that short needles are an evolutionary adaptation (Huang et al., ; Pakharkova, Kuzmina, Kuzmin, & Efremov, ; Ruby & Wright, ). Short needles of evergreen boreal conifers may be an adaptation to resist the wind drag and to reduce weight load due to snow or ice accumulation.…”

Variability studies for needle and wood traits of different half sib progenies of Pinus roxburghii Sargent

“…Variation in needle characteristics is also in congruence with Fowler and Morris (1977) in Pinus resinosa, Sagwal (1978) in P. roxburghii, Rajendra (2009) in P. merkusii, Nikolic et al (2013) in Picea omorika, Nikolic et al (2014) in Pinus heldreichii, Boratynska et al (2014) in P. mugo, Nikolic et al (2015) in P. peuce and Donnelly et al (2016) in P. sylvestris and Huang et al (2016) in Pinus yunnanensi.…”

“…Such studies have already been conducted by Pezzottii et al (1994) in Dactylis glomerata, Tsitsoni et al (1997) in P. halepensis, Tunctaner (2002), Kehl et al (2008), Singh et al (2012), Gupta (2005) in Salix, Singh (2006) in Populus sp., Banderas et al (2009) in Pinus leiophylla, Gouvea et al (2010) in rubber tree, Huang et al (2016) in P. yunnanensis. They have also reported different components having eigenvector greater than one, and explaining the different percent of variance by each component for different traits evaluated.…”