Differentiation of xylem elements involves cell expansion, secondary cell wall (SCW) deposition and programmed cell death. Transitions between these phases require strict spatiotemporal control. The function of Populus ERF139 (Potri.013G101100) in xylem differentiation was characterized in transgenic overexpression and dominant repressor lines of ERF139 in hybrid aspen (Populus tremula × tremuloides). Xylem properties, SCW chemistry and downstream targets were analyzed in both types of transgenic trees using microscopy techniques, Fourier transform-infrared spectroscopy, pyrolysis-GC/MS, wet chemistry methods and RNA sequencing. Opposite phenotypes were observed in the secondary xylem vessel sizes and SCW chemistry in the two different types of transgenic trees, supporting the function of ERF139 in suppressing the radial expansion of vessel elements and stimulating accumulation of guaiacyl-type lignin and possibly also xylan. Comparative transcriptomics identified genes related to SCW biosynthesis (LAC5, LBD15, MYB86) and salt and drought stress-responsive genes (ANAC002, ABA1) as potential direct targets of ERF139. The phenotypes of the transgenic trees and the stem expression profiles of ERF139 potential target genes support the role of ERF139 as a transcriptional regulator of xylem cell expansion and SCW formation, possibly in response to osmotic changes of the cells.

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/nph.15960

An AP2/ERF transcription factor ERF139 coordinates xylem cell expansion and secondary cell wall deposition.

The shading of maize and self-shading are the key factors affecting the stem lignin biosynthesis and lodging resistance of soybean at middle and later growth stages in the strip intercropping system. A study was designed to explore the regulation mechanism of lignin metabolism and different planting densities; PD1, PD2, and PD3 were used having a total number of 17 plants m−2, 20 plants m−2, and 25 plants m−2, respectively, on the lodging resistance of strip intercropped soybean stem. Our results depicted that the lower planting density (PD1) appropriately promoted the leaf photosynthesis activities (Pn), increase the activity of lignin-related enzymes and the accumulation of carbohydrates in stems, and eventually enhanced the lodging resistance of the strip intercropped soybean stem. Correlation analysis also showed that the lodging resistance index of soybean stem was significantly correlated with the available light for soybean canopy and Pn strip intercropped soybean stem characteristics and activities of enzymes related to lignin synthesis among the different planting densities. The findings of our research will be useful in future studies to understand the relationship between different light environment, planting densities, and lodging resistance of intercropped soybean and also guide the optimum planting density in maize–soybean intercropping system.

/pdf/effects-of-multiple-planting-densities-on-lignin-metabolism-42w8p1xidm.pdf

Effects of Multiple Planting Densities on Lignin Metabolism and Lodging Resistance of the Strip Intercropped Soybean Stem

Stem bending or lodging caused by insufficient stem strength is an important limiting factor for plant production. Secondary cell walls play a crucial role in plant stem strength, but whether WRKY transcription factors can positively modulate secondary cell wall thickness are remian unknown. Here, we characterized a WRKY transcription factor PlWRKY41a from herbaceous peony (Paeonia lactiflora), which was highly expressed in stems. PlWRKY41a functioned as a nucleus-localized transcriptional activator and enhanced stem strength by positively modulating secondary cell wall thickness. Moreover, PlWRKY41a bound to the promoter of the XYLOGLUCAN ENDOTRANSGLUCOSYLASE/HYDROLASE4 (PlXTH4) and activated the expression of PlXTH4. PlXTH4-overexpressing tobacco (Nicotiana tabacum) had thicker secondary cell walls, resulting in enhanced stem strength, while PlXTH4-silenced P. lactiflora had thinner secondary cell walls, showing decreased stem strength. Additionally, PlWRKY41a directly interacted with PlMYB43 to form a protein complex, and their interaction induced the expression of PlXTH4. These data support that the PlMYB43-PlWRKY41a protein complex can directly activate the expression of PlXTH4 to enhance stem strength by modulating secondary cell wall thickness in P. lactiflora. The results will enhance our understanding of the formation mechanism of stem strength and provide a candidate gene to improve stem straightness in plants.

The herbaceous peony transcription factor WRKY41a promotes secondary cell wall thickening to enhance stem strength.

Agrivoltaic systems (AV) combine agricultural activities with the production of electricity from photovoltaic (PV) panels on the same land area. The concept of AV systems was introduced in 1982 by Goetzberger and Zastrow, but only more recently have the increased environmental concerns and the favorable economic and political frameworks stimulated a growing interest in this technology. A critical issue in the development of AV is the selection of crops that can grow profitably under the micrometeorological conditions generated by AV systems. This experiment studied the effect of four different shade depth treatments (AV1 = 27%, AV2 = 16%, AV3 = 9%, and AV4 = 18%) on the morphology, physiology, and yield of a soybean crop grown under a large-scale AV system. The field results were used to validate the output of a simulation platform that couples the crop model GECROS with a set of algorithms for the estimation and spatialisation of the shading, radiation, and crop-related outputs. Crop height, leaf area index (LAI), and specific leaf area (SLA) all increased under the most shaded AV areas compared to the full light (FL, control) conditions. On average, under an AV system, the grain yield and the number of pods per plant were reduced by 8% and 13%, and in only one area (AV2) was a slight increase in grain yield (+4.4%) observed in comparison to the FL. The normalised root mean square error (nRMSE) value of the predicted grain yield differed from the observed grain values of 12.9% for the FL conditions, 15.7% in AV1, 16.5% in AV2, 6.71% in AV3, and 2.82% in AV4. Although the model simulated the yield satisfactorily, the results of the RMSE revealed that the model tends to underestimate the yield with an increase in shade, particularly for the AV1 and AV2 conditions.

/pdf/agrivoltaic-system-and-modelling-simulation-a-case-study-of-2ivxb68j.pdf

Agrivoltaic System and Modelling Simulation: A Case Study of Soybean (Glycine max L.) in Italy

Within each species, leaf traits such as light-saturated photosynthetic rate or dark respiration rate acclimate to local light environment. Comparing only static physiological traits, however, may not be sufficient to evaluate the effects of such acclimation in the shade because the light environment changes diurnally. We investigated leaf photosynthetic and morphological acclimation for a perennial herb, butterbur (Petasites japonicus (Siebold et Zucc.) Maxim. subsp. giganteus (G.Nicholson) Kitam.) (Asteraceae), in both a well-lit clearing and a shaded understory of a temperate forest. Diurnal changes in light intensity incident on the leaves were also measured on a sunny day and an overcast day. Leaves in the clearing were more folded and upright, whereas leaves in the understory were flatter. Leaf mass per area (LMA) was approximately twofold higher in the clearing than in the understory, while light-saturated photosynthetic rate and dark respiration rate per unit mass of leaf were similar between the sites. Consequently, both light-saturated photosynthetic rate and dark respiration rate per unit area of leaf were approximately twofold higher in the clearing than in the understory, consistent with previous studies on different species. Using this experimental dataset, we performed a simulation in which sun and shade leaves were hypothetically exchanged to investigate whether such plasticity increased carbon gain at each local environment. As expected, in the clearing, the locally acclimated sun leaves gained more carbon than the hypothetically transferred shade leaves. By contrast, in the understory, the daily net carbon gain was similar between the simulated sun and shade leaves on the sunny day due to the frequent sunflecks. Lower LMA and lower photosynthetic capacity in the understory reduced leaf construction cost per area rather than maximizing net daily carbon gain. These results indicate that information on static photosynthetic parameters may not be sufficient to evaluate shade acclimation in forest understories.

Photosynthetic and Morphological Acclimation to High and Low Light Environments in Petasites japonicus subsp. giganteus

Insufficient light intensity inhibits the growth of cultivated herbaceous peony and decreases its economic value. Owing to the increased demand for shade-tolerant herbaceous peony, the selection of appropriate parents for hybridization is essential. Paeonia anomala, Paeonia intermedia and Paeonia veitchii can grow under shade conditions in their natural habitats; however, their photosynthetic capacities under shade have not been studied. In this study, we simulated low light intensity (30% sunlight) and evaluated the morphological, photosynthetic and chlorophyll fluorescence parameters of these three species. Moreover, the shade tolerance of these species as well as two common cultivars (Paeonia lactiflora 'Da Fugui', which is suitable for solar greenhouse cultivation, and P. lactiflora 'Qiao Ling', which is not suitable for solar greenhouse cultivation) was evaluated. The results showed that under shade, the leaf area of P. anomala and P. intermedia increased, the single flowering period of P. intermedia and P. veitchii was prolonged, and the flower color of P. veitchii faded. With respect to P. anomala, P. intermedia and P. veitchii, shade eliminated the photosynthetic 'lunch break' phenomenon and decreased photoinhibition at midday. Furthermore, the maximum photochemical efficiency (Fv/Fm) and maximum primary photochemical yield (Fv/Fo) of photosystem II (PSII) in the three species improved significantly, and their changes in light dissipation were different. The shade tolerance of the tested accessions was in the order P. veitchii > P. intermedia > P. anomala > 'Da Fugui' > 'Qiao Ling', showing that the three wild species were better adapted to low light intensity than the cultivars. Thus, P. anomala, P. intermedia and P. veitchii could potentially be used in the development of shade-tolerant herbaceous peony cultivars.

Shade effects on growth, photosynthesis and chlorophyll fluorescence parameters of three Paeonia species.

Lack of structural components results in inflorescence stem bending. Differentially expressed genes involved in lignin and hemicellulose biosynthesis are vital; genes involved in cellulose and glycan biosynthesis are also relevant. An erect inflorescence stem is essential for high-quality cut herbaceous peony flowers. To explore the factors underlying inflorescence stem bending, major cell walls contents were measured, and stem structure was observed in two herbaceous peony varieties with contrasting stem straightness traits (‘Da Fugui’, upright; ‘Chui Touhong’, bending). In addition, Illumina sequencing was performed and weighted correlation network analysis (WGCNA) was used to analyze the results. The results showed significant differences in lignin, hemicellulose and soluble sugar contents, sclerenchyma and xylem areas and thickening in cell walls in pith at stage S3, when bending begins. In addition, 44,182 significantly differentially expressed genes (DEGs) were found, and these DEGs were mainly enriched in 36 pathways. Among the DEGs, hub genes involved in lignin, cellulose, and xylan biosynthesis and transcription factors that regulated these process were identified by WGCNA. These results suggested that the contents of compounds that provided cell wall rigidity were vital factors affecting inflorescence stem straightness in herbaceous peony. Genes involved in or regulating the biosynthesis of these compounds are thus important; lignin and hemicellulose are of great interest, and cellulose and glycan should not be ignored. This paper lays a foundation for developing new herbaceous peony varieties suitable for cut flowers by molecular-assisted breeding.

Transcriptome and weighted correlation network analyses provide insights into inflorescence stem straightness in Paeonia lactiflora.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Huiyan Yang

Author Tools

Chat about Author

Papers

Shade effects on growth, photosynthesis and chlorophyll fluorescence parameters of three Paeonia species.

Transcriptome and weighted correlation network analyses provide insights into inflorescence stem straightness in Paeonia lactiflora.