Study On Morphological Traits And Major Economic Characters Variation Of Natural Population In Listea Cubeba

Listea cubeba （Lour.） Pers.（Litsea, Lauraceae）is an important industrial speciesdistributed in China and Southeast Asia, the fruit of which can produce essencial oil as thematerial for flavor and fragrance industries. It is a shrub and small arhor. The varieties isevident among L. cubeba poupulations in the natural distribution areas. However, theknowledge about its genetic variation is so far less known. To develop the strategies for for L.cubeba further breeding and the nursing of genetic resource, the thesis focused on the studyabout the variation level and pattern of the L. cubeba populations on the phenotype, physiologyand biochemistry, and molecular levels. The results were concluded as follows.1) The significant differences in leaf and fruit traits were found among and withinpopulations, the mean phenotypic differentiation coefficient （Vst） among populations was60.19%, and the variation among populations was higher than that within population, whichindicated that the variance among populations was the main part of the phenotypic variation.The Vstof fruit shape, leaf shape, fruit weight, and seed weight were51.27%,66.66%,54.57%and72.29%respectivelyï¼›the coefficients of variation（VC）for the four kind of phenotypictraits were6.60%,16.91%,19.71%and13.40%respectively. Obviously, the traits stability offruit was higher than that of other traits. Correlation analysis revealed there was significant orextremely significant correlation among10phenotypic traits, and phenotypic traits had worsecorrelation with geo-climate factors. The10L. cubeba populations investigated could bedivided into4groups according to the cluster analysis, and the classifications amongpopulations were not in accordance the geography distance. Moreover, there was no significantrelationship between geographic and mahalanobis distances calculated from all phenotypictraits, which further revealed L. cubeba leaf and fruit traits variation was discontinuous onspace.2) The extremely significant difference were idenfied in LCEO and LCFC among the10L.cubeba populations, which showed closely correlation with the differiation of longtitude and latitude. The LCEO of Jingdong population reached the highest （4.56%）, Fenyi population wasthe lowest （3.14%）; LCFC of Yongan population reached the highest （7.01%）while Bijie wasthe lowest （1.85%）. Moreover, variance of LCFC among the populations were beyond variancein the populations （Vst=57.87%）. Correlation analysis was made among LCEO, LCFC and thegeography-ecology factors. The results revealed that LCEO showed a reverse changecharacteristic with longitude, primarily affected by water and temperature of oil accumulationperiod, and that LCFC existed a similar change characteristic with longitude, mainly regulatedby water. The populations were mainly classified into2groups by clustering analysis,including southwest population and southeast population.3) The successful isolation of genomic DNA and establishment of AFLP amplificationsystem. The high quality genomic DNA as a PCR template were isolated from the bud tissue,genomic DNA could be digested in a hour by5U EcoR I and5U Mse I. The optical selectionamplification system was20uL reaction mix containing1.0U Taq DNA polymerase,2uL10×PCR buffer,1.8uL25mM MgCl₂,1.4uL2.5mM dNTP,100ng uL^-1primer each1.0uL.Clear and stable amplification band patterns were obtained and10pairs of AFLP primers withgood genetic diversity were selected according to the optimized reaction system.