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Pyankovia brachiata (Pall.) Akhani & Roalson 2007, is an annual plant belonging to the genus Pyankovia, family Amaranthaceae, which is widely distributed in the inland deserts of Northwest China. P. brachiata was previously categorized under the genus Salsola in Salsoleae and has been a long-standing topic of debate. Therefore, the complete chloroplast genome of P. brachiata must be studied to provide a theoretical reference for species classification. In this study, we sequenced P. brachiata samples and determined the species’ complete chloroplast genome. The complete chloroplast genome was 149,922 bp in length, with one large single copy (LSC: 83,565 bp), one small single copy (SSC: 18,535 bp), and two inverted repeat regions (IRa and IRb, 23,911 bp each). It contains 132 genes, including 87 protein-coding, eight rRNA, and 37 tRNA genes. The phylogenetic position showed that P. brachiata has the closest relationship with Caroxylon passerinum (accession number: NC057191.1). This study will provide genetic information and be beneficial to understanding the systematic position of P. brachiata within the Amaranthaceae.

Abstract Although the postdispersal functions of diaspore (fruit and its appendages) have been reported, little is known about their protective/defensive functions. In this context, diaspores with appendages (persistent inner tepals and/or fruit wings) that experienced predispersal herbivory by insects in natural populations of Rheum nanum were investigated, and the seed abortion percentage, seed and embryo masses, and germination of seeds from diaspores with different categories of insect herbivory were measured and compared. Predispersal insect herbivory of R. nanum diaspores was prevalent in the four investigated populations, but the percentage of diaspores with appendages (persistent inner tepals and and/or fruit wings) damaged by insects was significantly higher than that of diaspores with the pericarp damaged by insects. Seeds from diaspores with gnawed appendages experienced significantly less damage than those with gnawed pericarps. Importantly, we conclude that fruit appendages of R. nanum help to mechanically protect developing seeds from predispersal insect herbivory.

Since pollen characters can be used to help distinguish species, our aim was to determine if palynological information has taxonomic significance for Gagea species from Xinjiang, China. Gagea is widely distributed in north temperate and the subtropical zones. The genus has limited taxonomic characteristics and large morphological variation, which results in difficulty of species classification. Pollen morphology of 16 species of this genus was examined comprehensively via light microscope (LM) and scanning electron microscope (SEM). One qualitative and nine quantitative traits of the pollen grains were surveyed, followed by hierarchical cluster analysis (HCA). The pollen grains were bilaterally symmetrical heteropolar monads with a mono-sulcus and they were oblate or peroblate (Polar diameter (P) / Equatorial diameter (E) = 0.36–0.73) in shape and medium to large (P = 17.17–34.64 μm, E = 27.63–81.65 μm) in size. Three types of exine ornamentation were observed: perforate, microreticulate and reticulate cristatum. The HCA divided the 16 species into two groups. This research provides new data on pollen morphology for Gagea (the pollen morphology of eight species was reported for the first time). Pollen morphology also can be used to identify species with similar external morphology, such as G. nigra and G. filiformis. Furthermore, the study of pollen morphology not only provides new data for palynology research on Gagea, but also provides a basis for future classification of this genus.

IntroductionFruit wings serve various ecological functions, including facilitating wind dispersal, providing physical protection to seeds, and regulating seed germination. While many studies have reported the role of fruit wings in plants, little is known about their protective function during fruit development.MethodsIn this study, winged fruits damaged by insects in natural populations of three Zygophyllum species (Z. potaninii, Z. lehmannianum and Z. macropterum) were investigated. We measured and compared the percentage of damaged winged fruits, seed set, seed mass, seed germination, and seedling growth of different insect herbivory categories.ResultsThe results revealed that the percentage of winged fruits with damaged wings only (low predation) was significantly higher than that of with damaged both fruit wings and fruit bodies (high predation). Furthermore, winged fruits with low predation had significant higher seed set, seed mass, seed germination, and dry mass and relative growth rate (RGR) in the seedlings which grown from the seeds, than that from winged fruits with high predation.DiscussionThese results demonstrate that the presence of the fruit wings may provide protection for the seeds to alleviate harm from insect predation before dispersal. These findings provide new insights into the function of fruit wings and the reproductive strategies of desert plants.

Stilpnolepis centiflora, a monotypic genus of the Asteraceae, is an endemic desert species in Northern China. However, information on the chloroplast (cp) genome of this species is limited. In this study, we present the complete chloroplast genome sequence of S. centiflora obtained by high-throughput nextgeneration sequencing technology. The whole cp genome was 151017 bp long and comprised 133 genes, including 88 proteincoding genes, 37 tRNA genes, and 8 rRNA genes. The S. centiflora cp genome had a GC content of 37.35%. Phylogenetic tree revealed that S. centiflora was closely related to the taxa in the genus Artemisia and Chrysanthemum. Our results would be helpful for species identification and promote our understanding of the phylogeny of Stilpnolepis within the Asteraceae family.