Construction And Evaluation Of Core Collections Of Pepper(Capsicum Annuum Linn.)

Pepper (Capsicum anrtuum L) is belonging to the Solanaceae Capsicum.Pepper Germplasms contain huge heterosis and the difference of Floral characters lead to the difference of Outcrossing rate, so it is important to analyze floral characters and Construct core collections of Pepper in new period. Eight floral characters of81hot pepper germplasm were analyzed to reveal their correlations as well as to provide the scientific basis for breeding purposes.Morphological markers and molecular markers is widely used to build core collections.155pepper resources built core collection using Morphological markers and molecular markers based on UPGMA and genetic diversity parameters. The core collection consinsts57accessions.(1) The results indicated that they should be significantly partial correlations between flower width and stigma width (style length and exerted length of stigma, flower length and anther width, anther length and stigma length, flower width and style length). The correlation coefficient of the first three groups were negative and the last two groups were positive.The variation coefficient of stigma exsertion rate was the highest (101.11%) and stigma length was the second higher (43.72%).The two characters can be improved easilier by breeding.81germplasm resources can be divided into five groups by cluster analysis. The stigma exsertion rate of No.24and No.80were long,which were conducive to cross-pollination. and No.64was the smallest, which is negative and not conducive to cross-pollination. No.24,No.80and No.64can be used in genetic improvement of hot pepper variety.(2) The155pepper meterials has24kinds of sampling scheme based on Bailey1923. The meterials was classified using UPGMA (Markov distance/Minimum distance method)method of SAS19.0statistical software.the result showed that25%was the optimum sampling proportions based on CA、CRV、CRV、CVR、CHi、RPR. The core collection consinsts43accessions.(3) The pepper SSR-PCR reaction system was optimized using orthogonal design.The total reaction volume was20ul including dNTP0.15mmol/L、Mg2+2.625mmol/L、Taq0.15U/uL、primers0.125umol/L and DNA template2.5ng/uL.(4)17SSR primers were screened out from200SSR primers which produced54Bands, of which54bands (100%) showed polymorphic.(5) The cluster analysis of SSR amplification results was conducted using UPGMA method of POPGENE statistical software, the result showed that25%was the optimum sampling proportions based on Shannon-weaver index and polymorphic loci. The core collection consinsting32accessions.(6) The cluster analys of SSR+phenotype amplification results was conducted Using UPGMA method of SAS19.0statistical software. the result showed that90%was the optimum sampling proportions based on ratio of phenotype retainedand(92.55%) and retention ratio of polymorphic loci (100%). The core collection consinsts57accessions.