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Pring, S.

Publications and source records attributed to Pring, S..

5 recordsLinked to original sources

Foliar application of mixed DAMP- and MAMP-oligosaccharides enhances root growth and fruit yield in okra and tomato in greenhouse experiments

Plants perceive diverse endogenous and microbial molecular patterns that shape their defense, growth, and productivity. Damage-associated molecular patterns (DAMPs) such as cello- and xylo-oligosaccharides, and microbe-associated molecular patterns (MAMPs) such as chitin-oligosaccharides, are known to promote both development and immunity. Here, we evaluated the combined application of these three oligosaccharides (Oligo-Mix) in okra and cherry tomato under greenhouse conditions. Regular foliar treatment with Oligo-Mix enhanced root elongation and biomass accumulation, and increased fruit number and yield in both crops. RNA-seq analysis of Oligo-Mix-treated tomato leaves showed coordinated induction of photosynthetic genes, components of the translational machinery, cell-wall remodeling factors, and enzymes involved in flavonoid/anthocyanin biosynthesis, indicating broad enhancement of metabolic capacity and protective secondary pathways. Together, these results demonstrate that Oligo-Mix functions as a biostimulant that supports both vegetative growth and fruit production, offering a sustainable approach to improving crop performance.

plant biology↗

Antennal RNAseq reveals odorant receptors with sex-biased expression in the common eastern firefly, Photinus pyralis

BackgroundWith their charismatic nighttime flashes, fireflies are a classic organismal system for studying visual mating signal evolution. However, across their diversity, fireflies employ a variety of mating strategies that include both chemical and visual signals. While phylogenetic evidence points to a common ancestor that relied on long-range pheromones, behavioral evidence suggests that light-dependent flashing fireflies do not use smell for mating. We tested this hypothesis by investigating the olfactory genetics of the nocturnal, light-using common eastern firefly, Photinus pyralis. In insects, odors are primarily detected by odorant receptor (OR) proteins embedded in the dendritic membranes of olfactory receptor neurons. If pheromones are part of mate signaling in light-using fireflies, then one or more OR genes should be upregulated in the antennae of the searching sex (males). We therefore annotated the complete suite of ORs from the genome of P. pyralis and measured expression of OR genes between the sexes. ResultsWe identified 102 ORs in the Photinus pyralis genome, including the conserved single-copy Orco. Our phylogenetic analysis showed lineage-specific OR diversification in P. pyralis relative to other beetle species. Differential expression analysis of male and female antennae and hind legs revealed that a subset of ORs are upregulated in antennae as compared to legs, suggesting a role in adult olfaction. Notably, PpyrOR6 was one of two genes, and the only OR, that was significantly upregulated between male and female antennae, suggesting a role in mating. ConclusionsThese findings increase known diversity of insect ORs in an understudied beetle family and suggest that bioluminescent fireflies use multimodal signals during mating.

evolutionary biology↗

Mixed DAMP/MAMP oligosaccharides promote both growth and defense against fungal pathogens of cucumber

Plants recognize a variety of environmental molecules, thereby triggering appropriate responses to biotic or abiotic stresses. Substances containing microbes-associated molecular patterns (MAMPs) and damage-associated molecular patterns (DAMPs) are representative inducers of pathogen resistance and damage repair, thus treatment of healthy plants with such substances can pre-activate plant immunity and cell repair functions. In this study, the effects of DAMP/MAMP oligosaccharides mixture (Oligo-Mix) derived from plant cell wall (cello-oligosaccharide and xylo-oligosaccharide), and fungal cell wall (chitin-oligosaccharide) were examined in cucumber. Treatment of cucumber with Oligo-Mix promoted root germination and plant growth, along with increased chlorophyll contents in the leaves. Oligo-Mix treatment also induced typical defense responses such as MAP kinase activation and callose deposition in leaves. Pretreatment of Oligo-Mix enhanced disease resistance of cucumber leaves against pathogenic fungi Podosphaera xanthii (powdery mildew) and Colletotrichum orbiculare (anthracnose). Oligo-Mix treatment increased the induction of hypersensitive cell death around the infection site of pathogens, which inhibited further infection and the conidial formation of pathogens on the cucumber leaves. RNA-seq analysis revealed that Oligo-Mix treatment upregulated genes associated with plant structural reinforcement, responses to abiotic stresses and plant defense. These results suggested that Oligo-Mix has beneficial effects on growth and disease resistance in cucumber, making it a promising biostimulant for agricultural application.

plant biology↗

Botrytis cinerea detoxifies the sesquiterpenoid phytoalexin rishitin through multiple metabolizing pathways

Botrytis cinerea is a necrotrophic pathogen that infects across a broad range of plant hosts, including high-impact crop species. Its generalist necrotrophic behavior stems from its ability to detoxify structurally diverse phytoalexins. The current study aims to provide evidence of the ability of B. cinerea to tolerate the sesquiterpenoid phytoalexin rishitin, which is produced by potato and tomato. While the growth of potato pathogens Phytophthora infestans (late blight) and Alternaria solani (early blight) was severely inhibited by rishitin, B. cinerea was tolerant to rishitin. After incubation of rishitin with the mycelia of B. cinerea, it was metabolized to at least six oxidized forms. Structural analysis of these purified rishitin metabolites revealed a variety of oxidative metabolism including hydroxylation at C7 or C12, ketone formation at C5, and dihydroxylation at the 10,11-olefin. Six rishitin metabolites showed reduced toxicity to P. infestans and A. solani, indicating that B. cinerea has at least 5 distinct enzymatic reactions to detoxify rishitin. Four host-specialized phytopathogenic Botrytis species, namely B. elliptica, B. allii, B. squamosa, and B. tulipae also had at least a partial ability to metabolize rishitin as B. cinerea, but their metabolic capacity was significantly weaker than that of B. cinerea. These results suggest that the ability of B. cinerea to rapidly metabolize rishitin through multiple detoxification mechanisms could be critical for its pathogenicity in potato and tomato.

microbiology↗

Induction of plant disease resistance by mixed oligosaccharide elicitors prepared from plant cell wall and crustacean shells

Basal plant immune responses are activated by the recognition of the conserved pathogen-associated molecular patterns (PAMPs), or breakdown molecules released from plants after damage by pathogen infection, so-called danger-associated molecular patterns (DAMPs). While chitin-oligosaccharide (CHOS), a primary component of the fungal cell wall, is most known as PAMP, plant cell wall-derived oligosaccharides, cello-oligosaccharides (COS) from cellulose and xylo-oligosaccharide (XOS) from hemicellulose, are representative DAMPs, which activate signaling steps similar to PAMP-induced immunity to elicit defenses and provide protection against pathogens. In this study, elicitor activities of COS prepared from cotton linters, XOS prepared from corn cobs as well as chitin-oligosaccharide (CHOS) from crustacean shells were comparatively investigated. In Arabidopsis, treatment of COS, XOS or CHOS triggered typical defense responses such as reactive oxygen species (ROS) production, activation of MAP kinases phosphorylation, callose depositions, and activation of the promoter for defense-related transcription factor WRKY33. When COS, XOS and CHOS were used at concentrations with similar activity in inducing ROS production and callose depositions, CHOS was particularly highly potent in activating the MAPK kinases and WRKY33 promoters. Among the COS and XOS with different degrees of polymerization (DP), cellotriose (DP3) and xylotetraose (DP4) showed the highest activity for the activation of WRKY33 promoter. Simultaneous treatment of COS, XOS and CHOS leads to a strong transcriptional change for defense-related genes, and gene ontology (GO) enrichment analysis of RNAseq data revealed that a mixture of three oligosaccharide (oligo-mix) effectively activate the plants disease resistance. In practice, treatment of the oligo-mix enhanced the resistance of tomato to powdery mildew, but plant growth was not inhibited but rather tended to be promoted, providing evidence that mixed oligosaccharides have beneficial effects on improving disease resistance in plants, making them a promising class of compounds for practical application.

plant biology↗