Study On Fruit Phenotypic Diversity Of Natural Population In Calligonum Mongolicum In Gansu Provice

Calligonum mongolicum is a common desert species in westen China,and it is oneof the most important indigenous tree species used for prevention and control ofdesertification. In order to conserve the remainders scientifically and utilize rationally, itwas necessary to make clear genetic diversity (GD) and population differentiationwithin the species. This study could provide the theoretical references and basic data forthe gene resources conservation and genetic improvement in this species.This study selected and investigated12natural populations of Calligonummongolicum in Gansu province, based on filed investigation and analysis of the naturaldistribution of Calligonum mongolicum.Fruit length, Fruit width, Fruit length-width ratio andthousand-kernel weight four phenotypic traits in30trees from each of12population inCalligonum mongolicum were measured in order to opened out the phenotypic variationof natural populations and found out the relationship between phenotypic variation ofnatural population and different distribution areas in Calligonum mongolicum. Themajor conclusions were described as follows:(1) The variance analysis for all the phenotypic traits showed that there wassignificantly difference among populations and there was significantly difference amongindividuals within population.(2) The mean phenotypic differentiation coefficient (Vst) ranged from85.89412%～97.12865%, the mean Vst was91.18077%,it showed that the variationamong populations (8.81923%) was smaller than that within population(91.18077%).(3) The order of Coefficient of variation (CV) within population was as follows:GZ3>WW1>GZ2>JT1>ZY1>GZ1>ZY3>WW2>ZY2>JT2>JT3>WW3.The mean CVof ten populations was0.217.The tendency of the CV within populations was JT1、GZ2、GZ3�'�WW1were highter than the total mean variation.(4) The order of Relative extreme valu（eR′i）of needle, cone, Fruit scale, Fruit wingand Fruit was Fruit length-width ratio（R′i=54.747）> Fruit length（R′i=53.937）> Fruit width（R′i=43.608）> thousand-kernel weigh（tR′i=36.527）. The order of Relative extreme value（R′i）in ten populations was: ZY3>WW2>GZ3>GZ2>WW3>JT2>WW1>JT1>ZY1>GZ1>ZY2>JT3. This order was the same as the CV, so we can conclusion that thevariance within population has greatly regularity.(5)There was greatly positive correlation between most of the phenotypic traits. Fruit length, Fruit width and thousand-kernel weight were thought the most importantphenotypic traits which were easy to measured in Calligonum mongolicum They caninfluence the germination percentage. So these traits were thought the important traits inthe early choosen for the Fruit.(6) The traits variation of natural populations within Calligonum mongolicumaffected mainly by latitude and longitude in spatial distribution.(7) According to the UPGMA cluster analysis, the12populations of theCalligonum mongolicum could be divided into four groups.This study indicated that there was rich phenotypic variation of phenotypic traits ofnatural population in Calligonum mongolicum in Gansu province. So this study providethe theoretical references and basic data for the genetic resources conservation andutilization and genetic improvement in Calligonum mongolicum.