| The Gramineous genus Zoysia includs eleven species, five species are present in our country, while Zoysiajaponica Steum is the most widely distributed and employed species and currently was identified as the rarely excellent germplasm of native turfgrass. Zoysia japonica Steum is found from 42.5 N to 23.5 N latitude and distributes from 126.5 E to 109 E longitudely. Zoysia japonica Steud. It is a warm-season turfgrass with characteristics of unknown distribution and wide ecological scope. Because of its great advantages in strong adaptability, drought-resistance, extension ability, wear-tolerance, elasticity and et al., it is widely used in the following fields:turf planting, ecological restoration, water&soil conservation, forage and so on. In view of its diversity in distribution area and growth habits, as well as its abundant variation and genetic diversity, systematic studies on different levels have been made on the ecological characters, population variation, comparative anatomy and AFLP molecular marker of 19 wild populations and 1 cultivated population of Zoysia japonica from its natural distribution area in China. Based on that, Zoysia japonica germplasm base in China has been set up. The main research fruits go as follows:I. 20 Zoysia japonica populations are distributed at altitude of 5m ~380m, and the pH of soil is from 6.5 to 8.1. Of which 60% of the soil collected is slightly alkali. The ecological environment type can be classified into four types which are hill grassland type, plain meadow type, seashore bottomland type and interstitial-meadow of farmland and woodland type. The predominant plant species lived in Zoysia japonica population are Carex humilis Potentilla chinensis Arundinella anomala Indigofera kirilowii Pennisetum alopecuroides, Artemisia capillaries, A. scoparia Lespedeza davuricus et al.II. Significant differences exist in 15 external morphological traits of zoysiajaponica such as length of creeping stem, number of spikelets, length of ligules and so on due to affection by different geological environment. Analysis of main constituents on datum of external traits of zoysia japonica shows the growth of creeping stem, length of spikelets, length of middle interoode of creeping stem were main elements resulted in differences of external morphologies exist among different populations. With the decrement of latitude,length and diameter of crawal stem, length and width of spikelets, length and width of leaf are declining, while the trend of spikelet number, spike median internode length, ligule length is increasing. These results showed that Zoysia japonica has plentiful genetic diversities. 20 populations can be classified into 8 groups based on the results clustering analysis. Clustering results were approximately identical with the geographical distribution of Zoysia japonica. Our research concluded that four populations can be used as eminent plant sources for turfgrass and forage breeding, this four populations originated from Rushan County and Zhuwang County in Rushan city of Shandong Province,Nanshui County in Zhuanghe city of Niaoning Province, Wafangdian County in Wafangdian city of Niaoning Province.III. Studies on comparative anatomy of Zoysia japonica vegetative organs of 20 different populations are made and the result shows that Zoysia japonica vegetative organ has great advantages over Poa pratensis vegetative organ in comparative anatomy. Firstly, in the Zoysia japonica root, the vessel elements with bigger diameter are present and plenty vascular bundle are exited in its stem .The cuticle of the stem epidermis and the lower and upper epidermis of the leaf are well developed .Secondly, there are extremely well developed bulliform cells situated between every two vascular bundles. Thirdly, The loading amount of the thickness of the layer of the mesophyll, the leaves thickness, the thickness of the upper and lower epidermis cell, the length of lower epidermis cell and the density of epidermis stomata of the leaf is the evidence of the ch...
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