Research On Two Good Strains Of Pears By Biogical Characteristics And Molecular Identification

The research of biological characteristics and molecular identification are the basic contents in theidentification of new pear cultivars, and the research on biological characteristics of new cultivars are theimportant basis for the cultivation and extension of new cultivars.This study takes two quality fragrant pearstrains85-8-34and85-12-20which by cross breeding with fragment pear as parent, and its parents (Zaosu,Fragment, Dangshan pear), hybrids(Xinli9,Xinli7) and mutation (Sha01) as the test materials, thebiological characteristics of9pear cultivars (strains) were studied, the phenological period,palynology,leaves and fruits characteristics were compared. Meanwhile, molecular marker technique wasused to identified the difference of85-8-34and85-12-20with other cultivars (strains), defined their goodproperties, the results would provide a reference for examination of new cultivars. The main results are asfollows:1、The two pear strains (85-8-34and85-12-20) budding in late March in Alar, the sprout period are13days and9days respectively. The flowering in early April and the flowering period about12days. Both thefull-bloom stage of them are7days. The fruit of85-12-20matured in early Septemper while85-8-34matured in late August. The former for mid-late maturity varieties and the latter for mid maturity varieties.2、The inflorescence of85-12-20are the umbrella room type cyme with the number of inflorescenceflowers3-8, which belongs to less flower type. The corolla diameter3.8cm,5pistils and16-20stamens.Light purple anther, the number of single anther pollen was5445.95, which belongs to more pollen countstypes. The pollen viability are91.95%. The pollen shape are extra length sphere, polar view are3crackcircle, stereographic view are long circle. The pollen wall are stripe-mesh and the frequency of perforationare1.93per μm2.The inflorescence of85-8-34are the umbrella room type cyme with the number of inflorescenceflowers6-9, which belongs to medium flower type. The corolla diameter3.65cm,5pistils and19-22stamens.Anther purple, the number of single anther pollen was1983.33, which belongs to less pollen counts types. The pollen viability are95.25%. The pollen shape are length sphere, polar view are3crack circle,stereographic view are long circle. The pollen wall are stripe-perforate and the frequency of perforation are1.61per μm2.3、85-12-20′s leaf shape is oval, shape of leaf base is roundness, shape of leaf apex acuminate or acute,acuminate mainly; Leaf margin has seta, serration, Status of leaf surface is amplexus.85-8-34′s leaf shapeis oval mainly; shape of leaf base has3types,are roundness,section and broadly cuneate; shape of leaf apexis tapering, Leaf margin has seta,serration, Status of leaf surface is amplexus.4、85-8-34′s fruit shape is mainly roundness, fruit surface bright, yellow-green background, blush,which are superior to Korla fragrant; Weight per fruit184g, fruit size and fruit core are both middle type;Soluble solids content12.25%, fruit firmness7.01kg/cm2, titratable acidity0.37%, soluble sugar concent8.27%, edible rate55.51%, sugar-acid radio22.35.85-12-20′s fruit shape is mainly roundness, fruit surface bright, yellow-green background, no blush,which has good appearance colour; Weight per fruit193g, fruit size and fruit core are both middle type;Soluble solids content12.35%, fruit firmness7.07kg/cm2, titratable acidity0.26%, soluble sugar concent5.32%, edible rate50.52%, sugar-acid radio20.46.5、The9samples of main pear cultivars (strains)in Pyrus which included species, hybrids and sportsmaterials were indentified and analysed by RAPD-PCR molecular markers method. The results indicatedthat18primers from screening of26randon decamer oligonucleotide primers could be good used inidentification of the pear materials. And successfully identify85-12-20and85-8-34are new cultivars,theprimers could distinguish9cultivars (strains) of pear are S136、S32、S28、OPVI4、OPG17.