Development and characterization of microsatellite markers for Lilium longiflorum (Liliaceae)

Exploration and Exploitation of Novel SSR Markers for Candidate Transcription Factor Genes in Lilium Species

Lilies (Lilium sp.) are commercially important horticultural crops widely cultivated for their flowers and bulbs. Here, we conducted large-scale data mining of the lily transcriptome to develop transcription factor (TF)-associated microsatellite markers (TFSSRs). Among 216,768 unigenes extracted from our sequence data, 6966 unigenes harbored simple sequence repeats (SSRs). Seventy-one SSRs were associated with TF genes, and these were used to design primers and validate their potential as markers. These 71 SSRs were accomplished with 31 transcription factor families; including bHLH, MYB, C2H2, ERF, C3H, NAC, bZIP, and so on. Fourteen highly polymorphic SSRs were selected based on Polymorphic Information Content (PIC) values and used to study genetic diversity and population structure in lily accessions. Higher genetic diversity was observed in Longiflorum compared to Oriental and Asiatic populations. Lily accessions were divided into three sub-populations based in our structure analysis, and an un-rooted neighbor-joining tree effectively separated the accessions according to Asiatic, Oriental, and Longiflorum subgroups. Finally, we showed that 46 of the SSR-associated genes were differentially expressed in response to Botrytis elliptica infection. Thus, our newly developed TFSSR markers represent a powerful tool for large-scale genotyping, high-density and comparative mapping, marker-aided backcrossing, and molecular diversity analysis of Lilium sp.

Biotechnological advances in Lilium

Modern powerful techniques in plant biotechnology have been developed in lilies (Lilium spp., Liliaceae) to propagate, improve and make new phenotypes. Reliable in vitro culture methods are available to multiply lilies rapidly and shorten breeding programs. Lilium is also an ideal model plant to study in vitro pollination and embryo rescue methods. Although lilies are recalcitrant to genetic manipulation, superior genotypes are developed with improved flower colour and form, disease resistance and year round forcing ability. Different DNA molecular markers have been developed for rapid indirect selection, genetic diversity evaluation, mutation detection and construction of Lilium linkage map. Some disease resistance-QTLs are already mapped on the Lilium linkage map. This review presents latest information on in vitro propagation, genetic engineering and molecular advances made in lily.

Microsatellite markers: what they mean and why they are so useful

Microsatellites or Single Sequence Repeats (SSRs) are extensively employed in plant genetics studies, using both low and high throughput genotyping approaches. Motivated by the importance of these sequences over the last decades this review aims to address some theoretical aspects of SSRs, including definition, characterization and biological function. The methodologies for the development of SSR loci, genotyping and their applications as molecular markers are also reviewed. Finally, two data surveys are presented. The first was conducted using the main database of Web of Science, prospecting for articles published over the period from 2010 to 2015, resulting in approximately 930 records. The second survey was focused on papers that aimed at SSR marker development, published in the American Journal of Botany's Primer Notes and Protocols in Plant Sciences (over 2013 up to 2015), resulting in a total of 87 publications. This scenario confirms the current relevance of SSRs and indicates their continuous utilization in plant science.