Association Analysis Of Calyx Morphology Traits With SSR Markers In Tomato

Tomato is among the most widely cultivated and consumed vegetables in the world.Froma long-term point of view, as people’s living standards and the level of knowledge continues toimprove, the requirements for vegetable’s quality of human are increasingly novel and strict.Sepal is an important part of flower and fruit in tomato, which affect the quality of fruit.Based on40tomato accessions of different types, we investigated the developmental processof sepal and indexes which can describe sepal morphology and its diversity. The resultsshowed as follows,1、Morphological characteristics of sepal’s developmental process in tomato. Tomatosepal’s morphology changes with development of flower and fruit, which is called persistentcalyx. The sepal development process was subdivided into7stages: close, slightly open, fullyopen, close again, open again, morphological change, final morphology. The finalmorphology also divided into five types: flat spread, upwarp, upright, up-curl anddown-wrap.2、Variations of characterizes for tomato sepal’s phenotypic traits in fruit maturity. Thecoefficient of variation of7sepal traits are crimpness (SEC,84.43%), surface area (SESA,45.54%), upwarp degree (SEUD,40.93%), Shape Coefficient (SESC,36.05%), length (SEL,35.02%), thickness (SET,29.46%) and width (SEW,24.61%). Tests of normality show thatall the traits were normally distributed expect SEC, which is log normally distributed.3、 Correlation analysis of sepal’s phenotypic traits. Correlation analysis revealedsignificantly positive correlation among SEL, SEW, SET and SESA. Between SESC(SEL/SEW) and SEL significantly positive correlation has been occured, but not betweenSESC and SEW. The correlation between SEC and SEUD was significantly positive, but therewere not significant correlations between these2traits and the other5traits.4、Principal component analysis of sepal’s phenotypic traits. The PCA shows that3PCscan represent the7traits, the cumulative contribution rate of PC1(size traits,45.51%), PC2(shape traits,21.67%) and PC3(morphology traits,20.33%) add up to87.5%.5types ofsepal morphology are described with the morphological indexes.5、Association analysis of calyx morphology traits with SSR markers in tomato. In thisstudy,33pairs are screened out from the62pairs of SSR markers in40tomato accessions. Atotal of97alleles are amplified from33pairs of primers,2.9alleles are amplified from each primer in average. PIC values of markers are between0.05-0.66, which are with an average of0.24. Analysis with STRUCTURE software, these40materials are divided into2subpopulation, which called Q1and Q2. Association analysis was calculated by general linearmodel (GLM) based on33SSR loci and7traits with TASEEL2.0software,8SSR markerswere detected significant associated with6traits at the P<0.05level. There are5SSRssignificant associated with SEUD, namely SSR117, SSR32, SSR331, SSR22, SSR578, ofwhich SSR32, SSR22, SSR331explained portion of phenotypic variation are10.65%,60.27%,29.40%,34.01%,15.17%respectively. SSR346is significant associated with SEL、SEW、SESA, explained portion of which to phenotypic variation are6.51%,5.93%,4.82%.