The size-dependent sex allocation model predicts that the relative resource allocation to female function often increases with plant size in animal-pollinated plants. If size effects on reproductive success vary depending on the environmental conditions, however, the size dependency may differ among populations. We tried to detect sitespecific variation in size-dependent sex allocation of a monocarpic hermaphrodite with reference to light availability. Multiple flowers and fruits were sampled from the individuals of Cardiocrinum cordatum, a monocarpic understory herb, and pollen, ovule and seed production were measured with reference to the plant size in two populations. Furthermore, frequency and foraging behavior of pollinator visitation was observed. Ovule production per flower increased with plant size in both populations, while pollen production per flower increased with size only in the population under sparse canopy. Therefore, proportional allocation to male function decreased with plant size in the population under closed canopy, but did not change in the population under sparse canopy. Pollinators usually visited only one flower per plant, indicating the negligible geitonogamous pollination in this species. Although seed production under closed canopy was lower than that under sparse canopy, seed-set rate per flower and seed mass per fruit were independent of plant size in either of the populations. Sizedependent sex allocation in this species was sitespecific, suggesting that not only resource storage before reproduction (i.e., plant size) but also resource availability of environment throughout the reproductive process (i.e., light availability) affect reproductive performance in this species.

In flowering plants, the relative importance of architecture and resource competition in allocation to pollen and ovules may vary with the resource pools or the overall resource availability of maternal plants.

Youngia japonica, a weed species distributed worldwide, has been widely used in traditional Chinese medicine. It is an ideal plant for studying the evolution of Asteraceae plants because of its short life history and abundant source. However, little is known about its evolution and genetic diversity. In this study, de novo transcriptome sequencing was conducted for the first time for the comprehensive analysis of the genetic diversity of Y. japonica. The Y. japonica transcriptome was sequenced using Illumina paired-end sequencing technology. We produced 21,847,909 high-quality reads for Y. japonica and assembled them into contigs. A total of 51,850 unigenes were identified, among which 46,087 were annotated in the NCBI non-redundant protein database and 41,752 were annotated in the Swiss-Prot database. We mapped 9,125 unigenes onto 163 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database. In addition, 3,648 simple sequence repeats (SSRs) were detected. Our data provide the most comprehensive transcriptome resource currently available for Y. japonica. C4 photosynthesis unigenes were found in the biological process of Y. japonica. There were 5596 unigenes related to defense response and 1344 ungienes related to signal transduction mechanisms (10.95%). These data provide insights into the genetic diversity of Y. japonica. Numerous SSRs contributed to the development of novel markers. These data may serve as a new valuable resource for genomic studies on Youngia and, more generally, Cichoraceae.

Examining variations in pollinator effectiveness can enhance our understanding of how pollinators and plants interact. Pollen deposition and seed production after a single visit by a pollinator are often used to estimate pollinator effectiveness. However, seed production is not always directly related to pollen deposition because not all pollen grains that are deposited on a stigma are compatible or conspecific. In the field, we tested pollinator effectiveness based on pollen deposition and the resulting seed production after single visits by different pollinator groups in a gynodieocious alpine plant Cyananthus delavayi (Campanulaceae). Our results showed that mean pollen deposition was generally inconsistent with mean seed production when comparisons were performed among different pollinator groups and sexes. In general, the correlations were not significant between pollen deposition and seed production in both perfect and female flowers after single visits by halictid bees, bumble bees, and hoverflies. We suggest seed set of virgin flowers after single visits is a more reliable indicator of pollinator effectiveness than pollen deposition and would be a better indicator of pollinator effectiveness for future studies.

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