Population Analysis of Diospyros lotus in the Northwestern Caucasus Based on Leaf Morphology and Multilocus DNA Markers.

Lidia S Samarina,Valentina I Malyarovskaya,Alexandra O Matskiv,Yuriy L Orlov,Gregory A Tsaturyan,Natalia G Koninskaya,Ruset M Shkhalakhova,Alexey V Ryndin,Ekaterina S Shurkina,Alexandr S Kuleshov,Maya V Gvasaliya,Ruslan S Rakhmangulov

doi:10.3390/ijms23042192

Abstract

Diospyros lotus is the one of the most frost-tolerant species in the Diospyros genera, used as a rootstock for colder regions. Natural populations of D. lotus have a fragmented character of distribution in the Northwestern Caucasus, one of the coldest regions of Diospyros cultivation. To predict the behavior of D. lotus populations in an extreme environment, it is necessary to investigate the intraspecific genetic diversity and phenotypic variability of populations in the colder regions. In this study, we analyzed five geographically distant populations of D. lotus according to 33 morphological leaf traits, and the most informative traits were established, namely, leaf length, leaf width, leaf index (leaf to length ratio) and the length of the fourth veins. Additionally, we evaluated the intraspecific genetic diversity of D. lotus using ISSR and SCoT markers and proposed a new parameter for the evaluation of genetic polymorphism among populations, in order to eliminate the effect of sample number. This new parameter is the relative genetic polymorphism, which is the ratio of polymorphism to the number of samples. Based on morphological and genetic data, the northernmost population from Shkhafit was phenotypically and genetically distant from the other populations. The correspondence between several morphological traits (leaf width, leaf length and first to fifth right vein angles) and several marker bands (SCoT5, SCoT7, SCoT30: 800–1500 bp; ISSR13, ISSR14, ISSR880: 500–1000 bp) were observed for the Shkhafit population. Unique SCoT and ISSR fragments can be used as markers for breeding purposes. The results provide a better understanding of adaptive mechanisms in D. lotus in extreme environments and will be important for the further expansion of the cultivation area for persimmon in colder regions.

Highlights

The Northwestern Caucasus is one of the northernmost growing regions for Diospyros, and this species was first introduced here between 1880 and 1890
A low level of general variability was observed for several traits: leaf length, leaf width, petiole length, Leaf Index (LI), Leaf Blade Index (LBI), length of the fourth veins, length of the fifth right vein, the angles of second, third, fourth and fifth veins
The Depressive-type ontogenetic strategy and a low level of intraspecific genetic diversity was observed in D. lotus in the Northwestern Caucasus

Summary

Introduction

The Northwestern Caucasus is one of the northernmost growing regions for Diospyros, and this species was first introduced here between 1880 and 1890. D. lotus is the most cold-tolerant species in the genus Diospyros and is important for the development of new cold-tolerant varieties and is often used as a cold-tolerant rootstock for D. kaki, allow them to survive extreme temperatures down to −20 ◦C, with good yields [1,2]. The index of vitality of coenopopulation (IVC) is one of the most important diagnostic characteristics of coenopopulations It indicates the general status of populations and is used to count the ecological plasticity of the species [23]. These parameters help to evaluate the phenotypic plasticity of populations, reveal the mechanisms by which species acclimate in colder regions, and establish the most reliable morphological indicators of cold adaptation

Objectives

Results

Conclusion