Search

Switchgrass (Panicum virgatum L.) is a promising perennial bioenergy crop that achieves high yields with relatively low nutrient and energy inputs. Modification of cell wall composition for reduced recalcitrance can lower the costs of deconstructing biomass to fermentable sugars and other intermediates. We have engineered overexpression of OsAT10, encoding a rice BAHD acyltransferase and QsuB, encoding dehydroshikimate dehydratase from Corynebacterium glutamicum, to enhance saccharification efficiency in switchgrass. These engineering strategies demonstrated low lignin content, low ferulic acid esters, and increased saccharification yield during greenhouse studies in switchgrass and other plant species. In this work, transgenic switchgrass plants overexpressing either OsAT10 or QsuB were tested in the field in Davis, California, USA for three growing seasons. No significant differences in the content of lignin and cell wall-bound p-coumaric acid or ferulic acid were detected in transgenic OsAT10 lines compared with the untransformed Alamo control variety. However, the transgenic overexpressing QsuB lines had increased biomass yield and slightly increased biomass saccharification properties compared to the control plants. This work demonstrates good performance of engineered plants in the field, and also shows that the cell wall changes in the greenhouse were not replicated in the field, emphasizing the need to validate engineered plants under relevant field conditions.

The widely used rice variety Lijiangxintuanheigu (LTH) shows a universal susceptibility to thousands of Magnaporthe oryzae isolates, the causal agent of devastating rice blast, making LTH an ideal line in resistance (R) gene cloning. However, the underlying genetic mechanism of the universal susceptibility has not been fully revealed because of the lack of a high-quality genome. Here, we took a genomic approach together with experimental assays to investigate LTHs universal susceptibility to rice blast. Using Nanopore long reads, we assembled a chromosome-level genome. Millions of genomic variants were detected by comparing LTH with 10 other rice varieties, of which large-effect variants could affect plant immunity. Gene family analyses show that the number of R genes and leucine-rich repeat receptor-like protein kinase (LRR-RLK)-encoding genes decrease significantly in LTH. Rice blast resistance genes called Pi genes are either absent or disrupted by genomic variations. Additionally, residual R genes of LTH are likely under weak pathogen selection pressure, and other plant defense-related genes are weakly induced by rice blast. In contrast, the pattern-triggered immunity (PTI) of LTH is normal, as demonstrated by experimental assays. Therefore, we conclude that weak effector-trigger immunity (ETI)-mediated primarily by Pi genes but not PTI results in the universal susceptibility of LTH to rice blast. The attenuated ETI of LTH may be also associated with reduced numbers of R genes and LRR-RLKs, and minimally functional residual defense-related genes. Finally, we demonstrate the use of the LTH genome by rapid cloning of the Pi gene Piak from a resistant variety.

Based on the case of the oil-gas separator for engine parts, this article has found the key steps to improve the cleanliness level by extracting and analyzing the impurity particles on its surface, and has reached the limit requirements in the enterprise standard. The whole detection process is divided into two parts: particle extraction and analysis. The impurity particles on the surface of the sample are extracted and collected by pressure washing, and the weight and size of the impurity particles are analyzed using a high-precision balance and a microscope. The test results show that the weight of the impurity particles on the surface of the oil and gas separator is 1.68 mg, and the maximum particle size is 887.31μm, which does not meet the product standard requirements. Through the analysis of the actual situation of the case to find the reasons and formulate measures, the final weight of the impurity particles on the surface of the improved sample is 1.22mg, and the maximum particle size is 481.40μm, which effectively improves the cleanliness level of the oil and gas separator.

At present, China has become the largest automobile production and sales country in the world, and the second largest lubricant consumption country. It is of great significance to establish China’s independent certification and evaluation system for lubricants.In recent years, China’s heavy-duty diesel engine has basically realized the technology autonomy, and the mode of lubricant evaluation standard equivalent to API specification is not suitable for China’s national conditions. It is imperative to develop a diesel engine oil quality evaluation research that is suitable for China’s national conditions. This paper mainly introduces a series of research on the performance difference of JAC 2.0TCI engine based on the physicochemical, wear and sediment evaluation of different reference oils under the condition of fuel dilution.

This paper selects 6 gasoline detergent synergists and 6 diesel detergent synergists that are mainstream in the market. The changes in mass, volume, hardness, size and surface morphology of the main components of the engine fuel supply system after being immersed in fuel containing detergent synergists for 28 days were studied,and these changes are compared with the benchmark fuel. The results show that most of the fuel detergent synergists have almost no corrosive effect on the engine fuel supply system components or are close to the reference fuel, but some gasoline detergent synergists have a slight corrosive swelling effect on the gasoline fuel supply system.

Melatonin is a low‐cost natural small indole molecule with versatile biological functions. However, melatonin's fungicidal potential has not been fully exploited, and the mechanism remains elusive. Here, we report that melatonin broadly inhibited 13 plant pathogens. In the rice blast fungal pathogen Magnaporthe oryzae, melatonin inhibited fungal growth, formation of infection‐specific structures named appressoria, and plant infection, reducing disease severity. Melatonin entered fungal cells efficiently and colocalized with the critical mitogen‐activated protein kinase named Mps1, suppressing phosphorylation of Mps1. Melatonin's affinity for Mps1 via two hydrogen bonds was demonstrated using surface plasmon resonance and chemical modifications. To improve melatonin's efficiency, we obtained 20 melatonin derivatives. Tert‐butyloxycarbonyl melatonin showed a 25‐fold increase in fungicidal activities, demonstrating the feasibility of chemical modifications in melatonin modification. Our study demonstrated the broad‐spectrum fungicidal effect of melatonin by suppressing Mps1 as one of the targets. Through further systematic modifications, developing an eco‐friendly melatonin derivative of commercial values for agricultural applications appears promising. [ABSTRACT FROM AUTHOR]

Ustilaginoidea virens, causing rice false smut (RFS) is an economically important ascomycetous fungal pathogen distributed in rice-growing regions worldwide. Here, we identified a novel transcription factor UvCGBP1 (Cutinase G-box binding protein) from this fungus, which is unique to ascomycetes. Deletion of UvCGBP1 affected development and virulence of U. virens. A total of 865 downstream target genes of UvCGBP1 was identified using ChIP-seq and the most significant KEGG enriched functional pathway was the MAPK signaling pathway. Approximately 36% of target genes contain the AGGGG (G-box) motif in their promoter. Among the targets, deletion of UvCGBP1 affected transcriptional and translational levels of UvPmk1 and UvSlt2, both of which were important in virulence. ChIP-qPCR, yeast one-hybrid and EMSA confirmed that UvCGBP1 can bind the promoter of UvPmk1 or UvSlt2. Overexpression of UvPmk1 in the ∆UvCGBP1-33 mutant restored partially its virulence and hyphae growth, indicating that UvCGBP1 could function via the MAPK pathway to regulate fungal virulence. Taken together, this study uncovered a novel regulatory mechanism of fungal virulence linking the MAPK pathway mediated by a G-box binding transcription factor, UvCGBP1. [ABSTRACT FROM AUTHOR]

The article explores the impact of knocking out phosphatidate phosphohydrolase (PAH) genes in plants, specifically rice and Arabidopsis. The researchers discovered that this knockout resulted in the accumulation of phosphatidic acid (PA), which in turn enhanced the plants' resistance to various pathogens. The study also revealed that PAHs are present in a wide range of plants and play a role in plant defense. The findings suggest that targeting PAH genes could be a promising approach for developing disease-resistant crops. Additionally, the researchers found that while the knockout of PAH genes improved resistance to pathogens, it also hindered plant growth. They identified changes in gene expression and lipid metabolism associated with the knockout, indicating that manipulating PAH genes could potentially enhance plant resistance without compromising yield. [Extracted from the article]

Brown spot disease of rice caused by Bipolaris oryzae results in severe yield losses. A high-quality genome was assembled using Nanopore sequencing data, resulting in a 36-Mb nuclear genome with 19 contigs and a mitogenome. This assembly provides valuable genetic resources for investigations of rice- B. oryzae interactions.

Rice blast fungus Magnaporthe oryzae serves as a model for studying fungal-plant interactions. In a recent phosphoproteomics study, Cruz-Mireles et al. comprehensively analyzed pathogenesis-related phosphorylation in M. oryzae with a focus on the Pmk1 pathway, integrating multiple signaling pathways and identifying new virulence factors. This study has broad implications for our understanding of fungal pathogenesis., Competing Interests: Declaration of interests No interests are declared., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bipolaris sorokiniana , one of the most devastating hemibiotrophic fungal pathogens, causes root rot, crown rot, leaf blotching, and black embryos of gramineous crops worldwide, posing a serious threat to global food security. However, the host-pathogen interaction mechanism between B. sorokiniana and wheat remains poorly understood. To facilitate related studies, we sequenced and assembled the genome of B. sorokiniana LK93. Nanopore long reads and next generation sequencing short reads were applied in the genome assembly, and the final 36.4-Mb genome assembly contains 16 contigs with the contig N 50 of 2.3 Mb. Subsequently, we annotated 11,811 protein-coding genes. Of these, 10,620 were functional genes, 258 of which were identified as secretory proteins, including 211 predicted effectors. Additionally, the 111,581-bp mitogenome of LK93 was assembled and annotated. The LK93 genomes presented in this study will facilitate research in the B. sorokiniana -wheat pathosystem for better control of crop diseases. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license., Competing Interests: The author(s) declare no conflict of interest.