Construction Of Molecular MAP And QTL Analysis Of Leaf Traits In Anthurium Andraeanum

Anthurium andraeanum,a famous potted and cut flower,has a long-vase life and broad market.Creation of new varieties is the base for sustainable development and plays key role on the establishment of efficient and competitive industry of A.andraeanum.Molecular breeding is the developmental direction of A.andraeanum breeding,therefore,it is of great significance to construct molecular map and investigate on QTL mapping for the establishment of molecular breeding system.In this study,F₁ hybrids of A.‘Mystral'and A.‘Alabama'was used as a mapping population,and new SSR markers were developed and employed to construct the genetic maps of A.andraeanum.On the basis,the important ornamental QTLs were mapped.The main findings are as follows:?1?The analysis of genetic traits.Character separation obviously appeared in the hybrid progenies of‘Mystral'and‘Alabama'combination,and the separation degrees of different Characters were not the same,with the coefficient of variation between 14.95%and 26.85%,the variation coefficiency of flower character is the highest,followed by leaf character,and that of plant trait was the lowest.200 Individuals randomly selected from300 hybrid progenies were used as mapping populations.?2?Development of SSR marker.147 pairs of SSR primers were obtained by using of Premier 5.0 software,and subjected for polymorphism analysis,103 pairs of primers amplified clear bands in the parents,accounting for 70.31%of the primers.?3?Construction of genetic map of A.andraeanum.Of the 103 pairs of newly developed SSR primers,76 primers were polymorphic,accounting for 51.7%of the primers;of the 125 SSR markers reported,49 were polymorphic and accounted for 39.2%of the primers.A genetic linkage map was constructed through linkage analysis of 125 SSR markers by the use of JoinMap 4.0 software.The genetic linkage map contains 15 linkage groups and 74 SSR markers with a total map distance of 768.5 cM and an average distance of 10.39 cM.The estimated genome length of Anthurium was 934.88 cM,the coverage ratio of genetic map was 82.2%.?4?QTL mapping analysis.19 traits of mapping population including leaf and flower and plant traits was analyzed.The results indicated that eleven traits including Leaf Length,Leaf Width,Leaf Thickness,The Intensity of Green Color of Leaf upper Side,Panicle Length,Pedicel Length,Spathe Length,Spathe Depression,The Spathe Position Compared to Leaves,Plant Height and Plant Width showed continuous variation and conformed to normal distribution.The quantitative traits were subjected for QTL mapping by using of MapQTL5.0 software.The results proved that QTL-lt-1 was located at the region of130.2¹32.5 cM on LG1 linkage group,accounting for 11.3%phenotypic variation of leaf thickness,QTL-ligc-1 was located at the region of 41.7⁴3.2 cM on LG2 linkage group,accounting for 8.9%phenotypic variation of intensity of green color of leaf upper side.Through the above studies,76 new SSR markers were developed and a SSR molecular map containing 15 linkage groups was constructed.The QTLs of Leaf thickness and intensity of green color of leaf upper side were firstly identified and mapped on the molecular map.These results will lay a solid foundation for the mapping,cloning,functional analysis and molecular marker-assisted selection breeding of important genes in A.andraeanum.