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Artificial grasslands of F . kryloviana in the region surrounding Qinghai Lake have been observed to a decline in productivity following three years of establishment. Traditional fertilization practices, aimed at maintaining ecological balance, have predominantly focused on the application of phosphorus. However, it remains unclear whether phosphorus fertilizers offer a superior advantage over nitrogen fertilizers in sustaining productivity. Consequently, from 2017 to 2019, we conducted an experimental to assess the impact of nitrogen and phosphorus fertilization on forage yield and quality. We designed with four levels of phosphorus and two levels of nitrogen, resulting in eight distinct fertilizer combinations. Our experimental findings indicate that the degradation of artificial grasslands leads to a shift in the allocation pattern of aboveground biomass. There was a respective decrease of 68.2 % and 62.5 % in the biomass proportions of stems and ears, contrasted by a greater than 200 % increase in the biomass proportion of leaves. The application of nitrogen not only elevated the total aboveground biomass but also promoted a preferential allocation of biomass to stems and leaves, consequently enhancing the forage's crude protein content. Nitrogen fertilization significantly increased aboveground biomass, and crude protein content by 63.21 %, and 6 %, respectively. Phosphorus fertilization's impact varied annually but favored the distribution of biomass to stems and ears. The net photosynthetic rate improved by over 53.12 % with fertilizer application, although the differences among treatments were not statistically significant. The balanced application of nitrogen and phosphorus fertilizers significantly bolstered the aboveground biomass, ear biomass, stem biomass, leaf biomass, and crude protein content in varying years by 17.25 %-209.83 %, 34.7 %-438.9 %, 25.5 %-250.2 %, 18.4 %-133.3 %, and 10.21 %-25.62 %, respectively. Our analysis revealed that nitrogen-only fertilization exhibited the most optimal fertilizer use efficiency and economic returns. In conclusion, nitrogen fertilization is crucial for sustaining the productivity and quality of F. kryloviana artificial grasslands. The local practice of 75 kg ha -1 phosphorus fertilizer is detrimental to the maintenance of productivity in F. kryloviana artificial grasslands. This study offers valuable insights into the optimization of fertilization strategies for sustainable forage production within alpine regions., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Wenhui Liu reports financial support was provided by Qinghai innovation platform construction project. Wenhui Liu reports financial support was provided by China Agriculture Research System. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Sexual reproduction is crucial for population continuity in clonal plants. The effect of nutrient translocation between ramets on sexual reproduction of clonal plants under nitrogen addition remains unclear. In this study, we focused on clonal fragments of Leymus chinensis reproductive ramets with different number of vegetative ramets connected to tillering nodes. A series of pot experiments was conducted under nitrogen addition, including 13 C and 15 N bidirectional labelling of vegetative ramets and reproductive ramets at the milk-ripe stage, determination of the 13 C and 15 N amount translocated, and assessment of the quantitative characteristics, nitrogen and carbon concentrations of reproductive ramets and vegetative ramets. Nitrogen addition promoted the translocation of 13 C while inhibiting 15 N between vegetative ramets and reproductive ramets. With an increase in the number of connected vegetative ramets, the 13 C translocated by reproductive ramets and the 15 N translocated by reproductive and vegetative ramets gradually increased. The translocation of 13 C and 15 N between vegetative and reproductive ramets was bidirectional and unequal. The translocated amount of 13 C and 15 N from reproductive ramets to vegetative ramets was always higher than that from vegetative ramets to reproductive ramets. Nitrogen addition did not prominently affect the sexual reproductive performance of L. chinensis, whereas the number of connected vegetative ramets both positively and negatively affected sexual reproductive performance. Ramet biomass is an important driver of nutrient acquisition by L. chinensis ramets. We demonstrate for the first time that unequal nutrient translocation between ramets affects sexual reproductive performance in L. chinensis. The findings contribute to an enhanced understanding of the reproductive strategies of clonal plant populations in future environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

The bioecological characteristics of plants determine their status and role in the community. The advantages of dominant species in the community compared with companion species in terms of physiological and ecological characteristics remain unclear. When both dominant and companion species in grassland plant communities are clonal, these plants are able to share resources within clones (physiological integration). However, it is unclear how the clonal dominant and companion species differ in the effect of their physiological integration on sexual reproduction. We chose Leymus chinensis , the dominant species of the most widespread meadow plant communities in the semiarid and arid regions of northern China, and its main companion species L. secalinus , Calamagrostis ripidula , C. pseudophragmites , and C. epigeios and conducted a series of in situ field experiments in a homogeneous environment, including the determination of the phenotypic characteristics of reproductive ramets with connected (allowing physiological integration) and disconnected (preventing integration) tillering nodes for each species, as well as 15 N leaf labeling of ramet pairs at the milk-ripe stage. In the clonal populations of the five grasses, physiological integration between vegetative ramets and reproductive ramets interconnected by tillering nodes significantly increased the leaf, stem, inflorescence and ramet biomasses of reproductive ramets, and relative changes in ramet biomass were greatest in L. chinensis . 15 N labeling showed that vegetative ramets supplied nutrients to reproductive ramets through tillering nodes; the amount of translocated 15 N per unit of reproductive ramet biomass was highest in L. chinensis . Overall, our results indicate that in the five clonal grasses, physiological integration between functionally different ramets under tillering node connections had a significant positive effect on sexual reproduction, indicating interspecific consistency in the contribution of physiological integration to sexual reproduction between the dominant and companion species, but this positive effect was greater in the dominant species L. chinensis than in the four main companion species. Therefore, differences in the physiological integration ability between the dominant and main companion species, identified for the first time in this study, may explain, at least partly, the dominance of L. chinensis in the community., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer LD declared a past collaboration/shared affiliation with the author XY to the handling editor at the time of review., (Copyright © 2023 Guo, Li, Yang and Yang.)

Hordeum jubatum is a salt tolerant forage, which plays an important role in improving saline-alkali land and animal husbandry alkali-saline grassland. Hordeum jubatum has been gradually domesticated as an ornamental grass due to its special flower color. However, no domesticated varieties of H. jubatum plant have been reported worldwide. This study reported the complete chloroplast genome of wild H. jubatum , which was 136,871 bp in length, containing a pair of inverted repeats (IRA/IRB) of 21,608 bp separated by a small single-copy (SSC) area region of 12,799 bp and the large single-copy (LSC) region of 80,856 bp. A total of 133 genes, including 85 protein-coding genes (79 PCG species), 40 transfer RNA genes (32 tRNA species), and eight ribosomal RNA genes (four rRNA species) were predicted from the chloroplast genomes. The overall GC content was 38.25%, and the corresponding values of the LSC, SSC, and IR were 36.22%, 32.15%, and 43.85%, respectively. The phylogenetic analysis showed that wild H. jubatum was clustered closely with Hordeum bogdanii ., Competing Interests: The authors declare no conflicts of interest. The authors alone are responsible for the content and writing of this article., (© 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Clonal plants usually reproduce asexually through vegetative propagation and sexually by producing seeds. Physiological integration, the translocation of essential resources between ramets, usually improves vegetative reproduction. However, how physiological integration affects sexual reproduction has been less studied in clonal grasses. Here, we chose Hierochloe glabra , a major early spring forage of the eastern Eurasian steppe, and conducted a series of field experiments, including sampling reproductive ramets connected by tillering nodes to different numbers of vegetative ramets and 15 N leaf labeling of ramet pairs at the seed-filling stage. In the natural populations of H. glabra , vegetative ramets were taller, had more and larger leaves, and greater biomass than reproductive ramets. Except for reproductive ramet biomass, sexual reproductive characteristics significantly increased with an increase in the number and biomass of vegetative ramets connected to tillering nodes. 15 N labeling showed that vegetative ramets supplied nutrients to reproductive ramets through tillering nodes. Overall, our results indicate that significant differences in morphological characteristics and biomass allocation underlie resources translocation from vegetative ramets towards reproductive ramets. Physiological integration between different functional ramets can increase sexual reproductive performance, which will be beneficial to population persistence in H. glabra .

Sexual reproduction is vital for population adaptation in clonal plants. The flag leaf is considered to be the primary contributor to sexual reproduction in cereal crops, and there is no unified conclusion on the effect of the number of vegetative ramets on grain yield. However, what effects of the flag leaf and the number of vegetative ramets on sexual reproductive performance of clonal grasses are largely unknown. To test this, under field natural conditions, we grew the rhizomatous grass Leymus chinensis in a homogeneous environment and conducted studies concerning the growth, reproduction and physiology of reproductive ramets in clonal populations. We measured the growth characteristics of different aged leaves, dynamically measured the net photosynthetic rate of different aged leaves and organ biomass, measured the sexual reproductive characteristics of reproductive ramets that had different numbers of connecting vegetative ramets, and performed isotope ( 15 N) labeling of ramet pairs at the seed-filling stage. In L. chinensis clonal populations, from the heading stage, the photosynthetic contribution of the functional leaves to seed production was much greater than that of the flag leaf; the photosynthetic capacity of both the functional leaves and the flag leaf all gradually declined. Vegetative ramets translocated their own resources to the connected reproductive ramets, and a large proportion of translocated resources were allocated to the leaf and stem to sustain life activities; increase in the number of connecting vegetative ramets increased floret number, seed number, seed-setting rate, inflorescence biomass, seed biomass, and reproductive allocation of reproductive ramets, and these parameters significantly and positively correlated with the biomass of connecting vegetative ramets. We conclude that the functional leaf rather than the flag leaf of L. chinensis is the primary contributor to seed production. Reproductive ramets adopt a strategy of growth first and reproduction later to allocate the translocated resources between the organs, but vegetative ramets are very advantageous for sexual reproduction under the tillering node connection form in L. chinensis . Overall, our study implies that vegetative ramets not only play an important role in the spatial expansion but also in the sexual reproduction of clonal plant populations., (Copyright © 2020 Guo, Li, Zhou and Yang.)

Background and Aims: Monocarpic plants are those that flower, produce seeds and then die. Although most monocarpic plants are annual or biennial, some of them are perennial. However, relatively little is known regarding the biology of monocarpic perennials. Pyrenean saxifrage (Saxifraga longifolia) is a monocarpic perennial that is well adapted to high-mountain ecosystems. Here, we evaluated altitudinal changes in clonality in various populations growing in their natural habitat with particular emphasis on the physiological costs of clonal growth., Methods: We assessed the percentage of clonal plants in nine populations growing in their natural habitat, as well as the plant stress response of clonal and non-clonal plants, in terms of photoprotection and accumulation of stress-related phytohormones, in a 3-year study at Las Blancas (2100 m a.s.l.). We also evaluated the influence of plant size on the activation of defensive responses to biotic and abiotic stresses., Key Results: We found that 12 % of Pyrenean saxifrage plants growing at the highest altitudes (2100 m a.s.l.) produced lateral rosettes which survived the flowering of the main rosette and shared the same axonomorphic root, thus escaping monocarpic senescence. This clonal growth did not worsen the physiological performance of plants growing at this altitude. Furthermore, increased plant size did not negatively affect the physiology of plants, despite adjustments in endogenous stress-related phytohormones. In contrast, maturity led to rapid physiological deterioration of the rosette, which was associated with monocarpic senescence., Conclusions: This study shows that the evolution of clonality has allowed Pyrenean saxifrage to survive harsh environmental conditions and it provides evidence that harsh environments push plant species to their limits in terms of life form and longevity., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Premise: Polymorphic microsatellite markers were developed as a tool for genetic investigations of Filipendula vulgaris (Rosaceae) and related species., Methods and Results: Seventeen new polymorphic microsatellite markers were developed for F. vulgaris using the Illumina MiSeq platform. Polymorphism of the 17 loci was tested in three populations. We identified a total of 203 alleles, ranging from four to 19 per locus, with levels of observed and expected heterozygosity ranging from 0.267 to 1.000 and 0.461 to 0.899, respectively. Primers were also tested for cross-amplification in three related species. Seven loci successfully cross-amplified in F. camtschatica and F. ulmaria , whereas we detected positive cross-amplification in only three loci in Geum urbanum ., Conclusions: The newly developed microsatellite primers will serve as useful genetic tools for further population genetic studies on F. vulgaris and related species., (© 2019 Čortan et al. Applications in Plant Sciences is published by Wiley Periodicals, Inc. on behalf of the Botanical Society of America.)

Premise: Microsatellite markers were developed in the federally endangered species Liatris helleri (Asteraceae) to evaluate species boundaries with closely related congeners within the genus., Methods and Results: Using Illumina data, 17 primer pairs were developed in populations of L. helleri . The primers amplified motifs from tri- to hexanucleotide repeats with one to 17 alleles per locus. Primers were also tested for cross-amplification in L. aspera , L. microcephala , and L. pycnostachya ., Conclusions: The developed primers for L. helleri serve as a novel genetic tool for future investigations in this genus, allowing for more explicit species delineation as well as population genetic analyses.

Premise of the Study: We developed microsatellite markers to study clonal growth and interspecific hybridization in the Patagonian and subantarctic plant Hypochaeris incana (Asteraceae) and its closest relatives., Methods and Results: We developed primers for microsatellite loci from 454 sequence reads of genomic DNA of H. incana . We tested them on individuals of H. acaulis , H. hookeri , H. incana , H. palustris , and H. tenuifolia . We selected 15 polymorphic microsatellite loci, which delivered clearly scorable fragments in most or all species. With mean values between 0.7 and 0.8, the expected heterozygosity in populations of H. incana is high., Conclusions: Due to high levels of polymorphism, the developed markers make it possible to distinguish between genets and ramets in H. incana . In some markers, null alleles complicate the scoring of genotypes in tetraploids. All of the developed markers are suitable to study interspecific hybridization among this group of closely related species.

The sand-fixation of plants is considered to be the most effective and fundamental measure in desertification control in many arid and semi-arid regions. Carex brunnescens (Carex spp) and Leymus secalinus (Leymus), two perennial clonal herbs native to the Maqu degraded alpine areas of northwest China, are dominant and constructive species in active sand dunes that have excellent adaptability to fix sand dunes found to date. In order to study the ability and mechanism of sandland blowout remediation by two clone plants C. brunnescens and L. secalinus, the artificially emulated blowouts were set up in the populations of two clonal plants in the field. The results showed that both C. brunnescens and L. secalinus produced more new ramets in the artificially emulated blowouts than in the natural conditions, suggesting that the two clonal plants had strong ability in blowouts remediation; while the biomass, number of leaves and height of new ramets in the artificially emulated blowouts were less than in the natural conditions due to the restriction of poor nutrients in the artificially emulated blowouts. The ability of blowouts remediation by C. brunnescens was stronger than L. secalinus, as it generated more new ramets than L. secalinus in the process of blowouts remediation. The new ramets of L. secalinus in the blowouts remediation were mainly generated by the buds in the rhizomes which spread from outside of the blowouts; while those of C. brunnescens were generated both by the buds in the rhizomes which spread from outside, and by the buds in the rhizomes inside which were freed from dormancy in the deeper soil under wind erosion conditions. These findings suggest that through rapid clonal expansion capability, C. brunnescens and L. secalinus exhibited strong ability in blowouts remediation which can be one of the most effective strategies to restore and reconstruct degraded vegetations in Maqu alpine areas of northwest China.

Premise of the Study: Microsatellite loci for the native prairie perennial Echinacea angustifolia were developed and evaluated for future use in population structure and paternity studies. •, Methods and Results: A total of 50 trinucleotide microsatellite regions were identified though an enrichment protocol that prescreens for microsatellite repeats before ligating into a vector. Of these, 11 loci were polymorphic and in Hardy-Weinberg equilibrium in three populations with varying numbers of plants. The loci had between three and 14 alleles and collectively provided high paternity exclusion probabilities. •, Conclusions: These sets of microsatellite primers will provide researchers and land managers with valuable information on the population genetic structure and gene flow between fragmented prairie populations.

Patterns of seed mass variation in the perennial herb Asphodelus albus (Liliaceae) were studied in one population over 3 years (1988-1990) and in three populations during 1989. Plant size, phenology and several components of plant fecundity showed no effect on mean seed mass per plant. Mean seed mass varied among populations and among plants within populations. Significant variation was also found among years and among plants within year, but most of the variation was accounted for by the within-plant component. Withinfruit variation may be as important as between fruits within plant. Fruit position within the plant influenced seed mass, being heavier the seeds at the bottom of the stalk. However, the plants markedly differed in the proportion of the variation accounted for by the position effect. The correlation between seed number per fruit and seed mass showed an interaction with fruit position. Seeds from small broods were heavier than those from large ones, but only in the lower part of the stalk. Decline in seed mass towards the top of the stalk may be attributed to seasonal reduction in resource availability. In addition, the change in the relationship between seed number and mass might be due to changes in the "resolution" of the parent-offspring conflict, also related to nutrient availability.