| The strawberry genus, Fragaria, belong to the Rosaceae. This diverse genus contains 23 species at varying ploidy levels inclding diplolid, tetraplont, pentaploid, hexaploid, octploid, decaploid and dodecaploid. The modern cultivated strawberry (Fragaria ananassa Duch.) is octoploid (2n=8x=56), and is a direct descent of two naturally-occurring octoploid species, F. chiloensis and F. virginiana. The strawberry gain the producers and consumersˊgrace due to some advantages such as short-term enterprise, produce quicker results, earn more profits, protein-rich, vitamins-rich.Gray mold of strawberry is one of the major fungal diseases commonly take place during the culture and production of strawberry, which has caused tremendous economic losses in strawberry cultivations. Gray mould majorly harms the fruit of strawberry, especially during the fruit maturity season, and it posteriorly jeopardizes the petal, calyx, stem, blade and petiole. Ripened fruit would become light-brownish after being infected; the symptom would then progressively expand to the whole fruit, with rotten flesh and closely-spaced grey mold. For the green fruit, gray mould would cause light-brownish spot and afterward the fruit become dry rotten. Gray mould majorly happens during turning-color period and maturity season of fruit, especially during the later period. It normally causes a 10 to 50 percent decrease of production, due to which the farmers suffer very big economic losses. It is widely known that using chemical agents is the principal protection for the damage of gray mould all around the world, which could threaten the food security and the protective effectiveness couldn't come to requests as well. On the other hand, application of insecticides for a long term would cause other environmental problems.In our reseach, high susceptible strawberry parent Darselect (89), high resistant strawberry parent Sweet Charlie (103) to gray mold, the 34 F1 populations and 248 F2 populations were used. We have analyzed the inheritance model of resistance to gray mold in 248 F2 populations through inoculated with gray mold fungus. A combination of SSR and BSA was applied with the F2 population to identify molecular markers linked to the resistance gene of gray mold in strawberry. In order to accelerate molecular marker assisted breeding process of gray mold resistance disease in strawberry and find a mrker which can be linked to the gray mold-resistant gene.The results showed that the marker to be linked to the resistant gene, and the genetic distance between the resistant gene and'UFFa 01H05' was identified 15.9 cM. Resistance to gray mold was controlled by a single dominant gene. Zelkova schneideriana, also named as Zelkova schneideriana Hand-Mazz, blood ju, gallinaceous oil trees, etc. It is deciduous trees belong to Ulmaceae,Zelkova and protected as the nationalⅡlevel wild plants. As valuable hard broadleaf timber species, it has many advantage, such as its hard but flexible material quality, less expansion, not easily to become warped crack, beautiful and luster texture, meticulous structure. Along with season change, its leaf color is rich range from yellowish-brown to shallow red, so it is an excellent ornamental species.In this study, the leaf area and diameter breast height of twenty three varieties of Zelkova were measured at different developmental stage, the changing foliage color were detected and the determinations of anthocyanin content in the leaves through various stages were operated. Genetic diversity and similarity were analyzed in molecular level and the purpose of this study is further perfecting the evaluation of species resource in Zelkova schneideriana. The result showed that a total of 128 bands based on 20 primers were detected, out of which 116 were polymorphic (90.6%). As analyzed by POPGENE32, the average value of effective number of alleles, Nei′s gene diversity and shannon′s information index were 1.5930, 0.3394, 0.5007, respectively. Clustering analysis showed that the 23 varieties of Zelkova schneideriana could be distinctively classified into nine groups. This is accord with previous result made by morphological study.
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