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We investigated the effects of different planting seasons and gibberellic acid treatments on the growth and development of Gypsophila paniculata to explore new approaches to controlling the flowering period. Four different cultivars were selected and continually planted in July, September, and November in the low-latitude and high-altitude region of Kunming, China (25° N, 102° E). Results showed that the vegetative growth and flowering time of Gypsophila paniculata were prolonged and postponed when the planting time was delayed. Specifically, ‘My Pink’ showed 20% and 80% rosette rates when grown in autumn and winter, respectively, thus indicating that Gypsophila paniculata is sensitive to planting time. Moreover, GA₃ treatment not only can significantly promote vegetative growth but also can stimulate early flowering and suppress the occurrence of rosettes during winter. This is more specific to ‘My Pink’, which showed 40% and 80% reductions in rosette rates with four and eight GA₃ treatment applications, respectively. Our study showed that seasonal variations in the growth and development of Gypsophila paniculata and GA₃ treatment can effectively stimulate early flowering and suppress rosettes during winter.

Simple sequence repeat (SSR) markers are valuable for genetic and breeding applications, but SSR resources for the ornamental genus chrysanthemum (Chrysanthemum ×morifolium Ramat.) are still limited. Expressed sequence tags (ESTs) are sources of SSRs that represent an opportunity to develop SSRs to accelerate molecular breeding in chrysanthemum. In total, 4661 SSR loci were identified from 3823 SSR-containing unigenes in the chrysanthemum transcriptome with an average of one SSR per 6.98 kb. Of these SSR sequences, trinucleotide repeats (30.0%) predominated, followed by dinucleotide repeats (17.9%). In total, 1584 primer pairs were subsequently synthesized. By screening the parents and six individuals of the F₁ progeny, 831 (52.5%) valid EST-SSR markers were identified, of which 361 (43.4%) were polymorphic. The annotation of unigenes containing polymorphic SSRs indicated that 330 (93.5%) demonstrated significant homology to other plant protein sequences. Twenty-five polymorphic EST-SSR markers were further selected for transferability analysis and exhibited 93% amplification in six Ajania species and six other Chrysanthemum species. Based on genotyping of the 59 samples, neighbor-joining analysis revealed six phylogenetic groupings, which was confirmed by population structure analysis and principal component analysis (PCA). Phylogenetic relationships among the 59 samples revealed by SSRs were highly consistent with the traditional taxonomic classification of Chrysanthemum and Ajania. The polymorphism information content (PIC) values ranged from 0.29 to 0.86, with a mean of 0.67, indicating high levels of informativeness. This research reveals the SSR distribution characteristics of chrysanthemum and provides a large number of new EST-SSR markers for further genetic diversity studies, genetic mapping, and molecular marker-assisted selection breeding for chrysanthemum.

In this study, simple sequence repeat (SSR) and sequence-related amplified polymorphism (SRAP) markers were used to analyze the genetic diversity of 48 wild Vitis davidii accessions. A total of 78 distinct alleles were amplified by 11 SSR primers, and the average allele number was 8.8. The average observed heterozygosity (Ho) and expected heterozygosity (He) values were 0.785 and 0.814, respectively. The effective allele numbers ranged from 3.92 to 9.61. The average polymorphism information content (PIC) was 0.798. Twelve of 169 SRAP primer combinations were selected for SRAP analysis. A total of 188 bands were produced, and the average was 15.7 bands per primer combination; the average percentage of polymorphic bands was 84.0%. The average PIC was 0.76. The results of the clustering analysis based on SSR markers showed that the 48 wild V. davidii accessions could be classified into five main clusters and had a genetic similarity coefficient level of 0.68. The dendrogram obtained from the SRAP data showed that 48 wild V. davidii accessions could be classified into five main clusters and had a genetic similarity coefficient of 0.72. SSR and SRAP markers differentiated all accessions studied including those with a similar pedigree. We speculated on the origin of Ciputao 0941♀, Ciputao 0940♂, and Fu’an-ci-01 using SSR markers and used both SSR and SRAP markers to resolve homonymy. The result will be valuable for further management and protection of V. davidii germplasm resources.