A low-methane rice with high-yield potential realized via optimized carbon partitioning.

Global rice cultivation significantly contributes to anthropogenic methane emissions. The methane emissions are caused by methane-producing microorganisms (methanogenic archaea) that are favoured by the anoxic conditions of paddy soils and small carbon molecules released from rice roots. However, different rice cultivars are associated with differences in methane emission rates suggesting that there is a considerable natural variation in this trait. Starting from the hypothesis that sugar allocation within a plant is an important factor influencing both yields and methane emissions, the aim of this study was to produce high-yielding rice lines associated with low methane emissions. In this study, the offspring (here termed progeny lines) of crosses between a newly characterized low-methane rice variety, Heijing 5, and three high-yielding elite varieties, Xiushui, Huayu and Jiahua, were selected for combined low-methane and high-yield properties. Analyses of total organic carbon and carbohydrates showed that the progeny lines stored more carbon in above-ground tissues than the maternal elite varieties. Also, metabolomic analysis of rhizospheric soil surrounding the progeny lines showed reduced levels of glucose and other carbohydrates. The carbon allocation, from roots to shoots, was further supported by a transcriptome analysis using massively parallel sequencing of mRNAs that demonstrated elevated expression of the sugar transporters SUT-C and SWEET in the progeny lines as compared to the parental varieties. Furthermore, measurement of methane emissions from plants, grown in greenhouse as well as outdoor rice paddies, showed a reduction in methane emissions by approximately 70 % in the progeny lines compared to the maternal elite varieties. Taken together, we report here on three independent low-methane-emission rice lines with high yield potential. We also provide a first molecular characterisation of the progeny lines that can serve as a foundation for further studies of candidate genes involved in sugar allocation and reduced methane emissions from rice cultivation.

Characterisation of a low methane emission rice cultivar suitable for cultivation in high latitude light and temperature conditions.

Rice cultivation on paddy soil is commonly associated with emissions of methane, a greenhouse gas, but rice varieties may differ in their actual level of emissions. This study analysed methane emissions associated with 22 distinct rice genotypes, using gas chromatography, and identified the cultivar Heijing 5 from northern China as a potential low-methane rice variety. To confirm this and to examine whether Heijing 5 can perform similarly at higher latitudes, Heijing 5 was cultivated in field trials in China (lat. 32° N) and Sweden (lat. 59° N) where (i) methane emissions were measured, (ii) methanogen abundance in the rhizosphere was determined using quantitative PCR, and (iii) the concentrations of nutrients in water and of heavy metals in rice grain and paddy soil were analysed. The results demonstrated that the low-methane rice cultivar Heijing 5 can successfully complete an entire growth period at high-latitude locations such as central Sweden. Massively parallel sequencing of mRNAs identified candidate genes involved in day length and cold acclimatisation. Cultivation of Heijing 5 in central Sweden was also associated with relatively low heavy metal accumulation in rice grains and lowered nutrient losses to neighbouring water bodies.

High fructan barley lines produced by selective breeding may alter ß-glucan and amylopectin molecular structure.

Six cross-bred barley lines developed by a breeding strategy with the target to enhance the fructan synthesis activity and reduce the fructan hydrolysis activity were analyzed together with their parental lines, and a reference line (Gustav) to determine whether the breeding strategy also affected the content and molecular structure of amylopectin and ß-glucan. The highest fructan and ß-glucan content achieved in the novel barley lines was 8.6 % and 12 %, respectively (12.3-fold and 3.2-fold higher than in Gustav). The lines with low fructan synthesis activity had higher starch content, smaller building blocks in amylopectin, and smaller structural units of ß-glucans than the lines with high-fructan synthesis activity. Correlation analysis confirmed that low starch content was associated with high amylose, fructan, and ß-glucan content, and larger building blocks in amylopectin.

Improved bioenergy value of residual rice straw by increased lipid levels from upregulation of fatty acid biosynthesis.

BACKGROUND: Rice (Oryza sativa) straw is a common waste product that represents a considerable amount of bound energy. This energy can be used for biogas production, but the rate and level of methane produced from rice straw is still low. To investigate the potential for an increased biogas production from rice straw, we have here utilized WRINKLED1 (WRI1), a plant AP2/ERF transcription factor, to increase triacylglycerol (TAG) biosynthesis in rice plants. Two forms of Arabidopsis thaliana WRI1 were evaluated by transient expression and stable transformation of rice plants, and transgenic plants were analyzed both for TAG levels and biogas production from straw. RESULTS: Both full-length AtWRI1, and a truncated form lacking the initial 141 amino acids (including the N-terminal AP2 domain), increased fatty acid and TAG levels in vegetative and reproductive tissues of Indica rice. The stimulatory effect of the truncated AtWRI1 was significantly lower than that of the full-length protein, suggesting a role for the deleted AP2 domain in WRI1 activity. Full-length AtWRI1 increased TAG levels also in Japonica rice, indicating a conserved effect of WRI1 in rice lipid biosynthesis. The bio-methane production from rice straw was 20% higher in transformants than in the wild type. Moreover, a higher producing rate and final yield of methane was obtained for rice straw compared with rice husks, suggesting positive links between methane production and a high amount of fatty acids. CONCLUSIONS: Our results suggest that heterologous WRI1 expression in transgenic plants can be used to improve the metabolic potential for bioenergy purposes, in particular methane production.

LBP1C-2 from Lycium barbarum maintains skeletal muscle satellite cell pool by interaction with FGFR1.

Muscle stem cells, called satellite cells (SCs), are employed to repair and rebuild muscle. SC-based therapeutic strategies are urgently needed. In this study, we showed that Lycium barbarum extract (LBE) improved the number of SCs and enhanced muscle regeneration by promoting SC activation and self-renewal in both adult and aging mice. L. barbarum polysaccharide (LBP), the main component of LBE, also played a similar role. More importantly, LBP1C-2, a homogeneous polysaccharide isolated from LBP, was uncovered to be an active component in regulating SC function. Mechanism study revealed that LBP1C-2 might bind to FGFR1 to activate SCs and promote SC self-renewal through Spry1 upregulation. This might be the first study to show that LBE participated in the regulation of SCs, and the active components and targets of LBE were identified. This study lays a theoretical foundation for the medicinal or auxiliary medicinal use of L. barbarum in skeletal muscle.

LBP1C-2 from Lycium barbarum alleviated age-related bone loss by targeting BMPRIA/BMPRII/Noggin.

Age-related bone loss is unavoidable and effective safe drugs are in great need. The fruit of Lycium barbarum was recorded to strengthen bones in the "Ben Cao Gang Mu (Compendium of Materia Medica)". However, there lacks scientific explanation. Herein, we investigated L. barbarum water extract (LBE), L. barbarum polysaccharides (LBP) and the homogeneous polysaccharide LBP1C-2 on the bone loss in adult mouse, aging mouse and ovariectomized mouse models. LBE, LBP and LBP1C-2 all markedly increased bone mass and bone strength in these models and promoted osteoblast proliferation, differentiation and ossification. Mechanistic studies showed that LBP1C-2 binds directly to the BMP receptors (BMPRIA and BMPRII) and noggin, activates the phosphorylation of Smad and disrupts the interaction between noggin and BMPs. Our results clearly elucidate the mechanism, the critical component and the direct targets of L. barbarum and provide potentially safe natural products and new drug candidate against age-related bone loss.

A Novel Cuticular Protein-like Cpr21L Is Essential for Nymph Survival and Male Fecundity in the Brown Planthopper.

Cuticular proteins (CPs) are a large family and perform a variety of functions. However, the physiological roles of cuticle protein 21-like (Cpr21L) in the brown planthopper (Nilaparvata lugens, BPH), one of the most destructive insect pests of rice, are largely unclear. In this study, Cpr21L was revealed to be expressed in both BPH nymphs and adults, and the mRNA expression level was much higher in male adults than female adults. Spatially, the expression of Cpr21L in the testis was higher than in the ovary. The RNA interference (RNAi) of Cpr21L seriously decreased nymph survival, and no individual survived 8 days post-dsCpr21L injection. The RNAi of Cpr21L in adults also decreased the fertility of males, especially in the dsCpr21L♂ × dsGFP♀ group. The average number of eggs laid by one female in this group significantly decreased by 50.1%, and the eggs' hatchability decreased from 76.5% to 23.8% compared with the control (dsGFP♂ × dsGFP♀). Furthermore, observations under a stereomicroscope showed that the RNAi of Cpr21L severely impaired the development of the testes. Therefore, Cpr21L is essential for the nymphal survival and male fecundity of BPH, thus providing a possible target for pest control.

Achieving of high-diet-fiber barley via managing fructan hydrolysis.

High fructan content in the grain of cereals is an important trait in agriculture such as environmental resilience and dietary fiber food production. To understand the mechanism in determining final grain fructan content and achieve high fructan cereal, a cross breeding strategy based on fructan synthesis and hydrolysis activities was set up and have achieved barley lines with 11.8% storage fructan in the harvested grain. Our study discovered that high activity of fructan hydrolysis at later grain developmental stage leads to the low fructan content in mature seeds, simultaneously increasing fructan synthesis at early stage and decreasing fructan hydrolysis at later stage through crossing breeding is an efficient way to elevate grain diet-fiber content. A good correlation between fructan and beta glucans was also discovered with obvious interest. Field trials showed that the achieved high fructan barley produced over seven folds higher fructan content than control barley and pull carbon-flux to fructan through decreasing fructan hydrolysis without disruption starch synthesis will probably not bring yield deficiency.

Combined Transcriptome and Metabolome Profiling Provide Insights into Cold Responses in Rapeseed (Brassica napus L.) Genotypes with Contrasting Cold-Stress Sensitivity.

Low temperature is a major environmental factor, which limits rapeseed (Brassica napus L.) growth, development, and productivity. So far, the physiological and molecular mechanisms of rapeseed responses to cold stress are not fully understood. Here, we explored the transcriptome and metabolome profiles of two rapeseed genotypes with contrasting cold responses, i.e., XY15 (cold-sensitive) and GX74 (cold-tolerant). The global metabolome profiling detected 545 metabolites in siliques of both genotypes before (CK) and after cold-stress treatment (LW). The contents of several sugar metabolites were affected by cold stress with the most accumulated saccharides being 3-dehydro-L-threonic acid, D-xylonic acid, inositol, D-mannose, D-fructose, D-glucose, and L-glucose. A total of 1943 and 5239 differentially expressed genes were identified from the transcriptome sequencing in XY15CK_vs_XY15LW and GX74CK_vs_GX74LW, respectively. We observed that genes enriched in sugar metabolism and biosynthesis-related pathways, photosynthesis, reactive oxygen species scavenging, phytohormone, and MAPK signaling were highly expressed in GX74LW. In addition, several genes associated with cold-tolerance-related pathways, e.g., the CBF-COR pathway and MAPK signaling, were specifically expressed in GX74LW. Contrarily, genes in the above-mentioned pathways were mostly downregulated in XY15LW. Thus, our results indicate the involvement of these pathways in the differential cold-stress responses in XY15 and GX74.

Low-Cost Detection of Methane Gas in Rice Cultivation by Gas Chromatography-Flame Ionization Detector Based on Manual Injection and Split Pattern.

Rice cultivation is one of the most significant human-created sources of methane gas. How to accurately measure the methane concentration produced by rice cultivation has become a major problem. The price of the automatic gas sampler used as a national standard for methane detection (HJ 38-2017) is higher than that of gas chromatography, which greatly increases the difficulty of methane detection in the laboratory. This study established a novel methane detection method based on manual injection and split pattern by changing the parameters of the national standard method without adding any additional automatic gas samplers. The standard curve and correlation coefficient obtained from the parallel determination of methane standard gas were y = 2.4192x + 0.1294 and 0.9998, respectively. Relative standard deviation (RSD, <2.82%), recycle rate (99.67−102.02%), limit of detection (LOD, 0.0567 ppm) and limit of quantification (LOQ, 0.189 ppm) of this manual injection method are satisfying, demonstrating that a gas chromatography-flame ionization detector (GC-FID), based on manual injection at a split ratio (SR) of 5:1, could be an effective and accurate method for methane detection. Methane gases produced by three kinds of low-methane rice treated with oxantel pamoate acid, fumaric acid and alcohol, were also collected and detected using the proposed manual injection approach Good peak shapes were obtained, indicating that this approach could also be used for quantification of methane concentration.

A Lycium barbarum extract inhibits ß-amyloid toxicity by activating the antioxidant system and mtUPR in a Caenorhabditis elegans model of Alzheimer's disease.

Lycium barbarum, a traditional Chinese medicine, has been shown to have antioxidant properties and has a protective effect in many diseases related to oxidative stress, such as neurodegenerative diseases, cardiovascular diseases, and cancer. Although the neuroprotective effects of L. barbarum extract (LBE) have been reported in several studies, the underlying molecular mechanisms are still unclear. In this study, the transgenic Caenorhabditis elegans strain CL2006 was used to investigate the function and molecular mechanism of an LBE in Alzheimer's disease (AD). LBE had high antioxidant potential and effectively delayed Aß-induced paralysis in the CL2006 strain. LBE inhibited the production of excessive reactive oxygen species by inducing the SKN-1-mediated antioxidant system, thereby inhibiting the generation of Aß and inhibiting mitochondrial damage. Importantly, LBE reduced Aß levels by inducing FSHR-1-mediated activation of the mtUPR. Therefore, our study not only reveals a new mechanism of LBE in the treatment of AD but also identifies a novel strategy for the treatment of AD by enhancing the mtUPR.

GAPDH S-nitrosation contributes to age-related sarcopenia through mediating apoptosis.

The age-related loss of muscle mass and muscle function known as sarcopenia is a major public health problem among older people. Recent research suggests that activation of apoptotic signaling is a critical aspect of the pathogenesis of age-related sarcopenia. However, little information exists in the literature about the apoptotic mechanism of sarcopenia in aging. Herein, we report that elevated glyceraldehyde-3-phosphate dehydrogenase (GAPDH) S-nitrosation and apoptosis occur in sarcopenia during natural aging and that translocation of S-nitrosated GAPDH to the nucleus and S-nitrosated GAPDH-mediated apoptosis contributed to sarcopenia. The levels and sites of GAPDH S-nitrosation in muscle tissues of young, adult and old mice were studied with a quantitative S-nitrosation proteomic analysis approach. GAPDH S-nitrosation increased with aging, and the GAPDH modification sites Cys150, Cys154 and Cys245 were identified. The upregulated S-nitrosation of GAPDH relies on inducible nitric oxide synthase (iNOS) rather than enzymes involved in denitrosylation. Treatment with the iNOS inhibitor 1400W or mutation of GAPDH S-nitrosation sites alleviated apoptosis of C2C12 cells, further demonstrating that GAPDH S-nitrosation in aging contributes to sarcopenia. Taken together, these findings reveal a new cellular mechanism underlying age-related sarcopenia, and the demonstration of muscle loss mediated by iNOS-induced GAPDH S-nitrosation suggests a potential therapeutic strategy for sarcopenia.

RNAi-mediated silencing of the autophagy-related gene NlATG3 inhibits survival and fecundity of the brown planthopper, Nilaparvata lugens.

BACKGROUND: The brown planthopper (BPH), Nilaparvata lugens, is a serious insect pest of rice. Autophagy and its related gene ATG3 play multiple roles in insects. However, information about the functions of ATG3 in BPH (NlATG3) is unavailable, and its potential as a target for pest control remains unclear. RESULTS: RT-qPCR results showed a relatively low expression of NlATG3 in 1st-4th-instar nymphs, which increased through 9-day-old adults. The expression of NlATG3 increased continuously in 1-day-old through 5-day-old eggs, whereas it decreased thereafter. The mRNA level of NlATG3 was markedly higher in the ovary (1.16) and head (1.00) compared to the rest body parts of BPH adults. Injecting nymphs with dsNlATG3 at doses from 62.5 to 250 ng per insect had strong lethal effect upon them. For the 5th-instar nymphs, all individuals died within 5 days after receiving the dsNlATG3, and importantly, no individual successfully molted. Transmission electron microscopy revealed the new cuticle of nymphs injected with dsNlATG3 became loose and curved, which is clearly different from that of the control. Correspondingly, the obvious vesicles in epidermal cells disappeared after dsNlATG3-treatment. RNAi of NlATG3 significantly reduced the total number of eggs laid per female as well as the eggs' hatchability, especially in the dsNlATG3♀ × dsGFP♂ group, whose total number of eggs laid per female largely decreased by 80.4%, and whose eggs' hatchability was significantly reduced from 95.7% to zero, when compared with the control (dsGFP♀ × dsGFP♂). CONCLUSION: NlATG3 is a promising target for developing RNAi-based insect management strategies. © 2021 Society of Chemical Industry.

A Rapid and Sensitive Europium Nanoparticle-Based Lateral Flow Immunoassay Combined with Recombinase Polymerase Amplification for Simultaneous Detection of Three Food-Borne Pathogens.

Food-borne pathogens have become an important public threat to human health. There are many kinds of pathogenic bacteria in food consumed daily. A rapid and sensitive testing method for multiple food-borne pathogens is essential. Europium nanoparticles (EuNPs) are used as fluorescent probes in lateral flow immunoassays (LFIAs) to improve sensitivity. Here, recombinase polymerase amplification (RPA) combined with fluorescent LFIA was established for the simultaneous and quantitative detection of Listeria monocytogenes, Vibrio parahaemolyticus, and Escherichia coliO157:H7. In this work, the entire experimental process could be completed in 20 min at 37 °C. The limits of detection (LODs) of EuNP-based LFIA-RPA were 9.0 colony-forming units (CFU)/mL for Listeria monocytogenes, 7.0 CFU/mL for Vibrio parahaemolyticus, and 4.0 CFU/mL for Escherichia coliO157:H7. No cross-reaction could be observed in 22 bacterial strains. The fluorescent LFIA-RPA assay exhibits high sensitivity and good specificity. Moreover, the average recovery of the three food-borne pathogens spiked in food samples was 90.9-114.2%. The experiments indicate the accuracy and reliability of the multiple fluorescent test strips. Our developed EuNP-based LFIA-RPA assay is a promising analytical tool for the rapid and simultaneous detection of multiple low concentrations of food-borne pathogens.

Dual fluorescent immunochromatographic assay for simultaneous quantitative detection of citrinin and zearalenone in corn samples.

The presence of multiple mycotoxins in the agricultural products poses a serious threat to the health of humans and animals. Citrinin (CIT) causes slow growth in animals and damages the kidney function. Zearalenone (ZEN) causes chronic poisoning, abnormal functioning and even death in animals. Herein, a dual fluorescent immunochromatographic assay (DF-ICA) based on europium nanoparticles (EuNPs) was developed for the simultaneous detection of CIT and ZEN in the corn samples. After optimization, the limits of detection (LODs), IC50 and average recoveries for the simultaneous determination of CIT and ZEN were 0.06 and 0.11 ng/mL, 0.35 and 0.76 ng/mL, from 86.3% to 111.6% and from 86.6% to 114.4%, respectively. Moreover, the DF-ICA was validated by high performance liquid chromatography (HPLC) analyses, and a satisfactory consistency was obtained. In brief, this work demonstrates the feasibility of DF-ICA for simultaneous monitoring of CIT and ZEN in the corn samples.

Lycium barbarum Extracts Extend Lifespan and Alleviate Proteotoxicity in Caenorhabditis elegans.

Lycium barbarum berry (Ningxia Gouqi, Fructus lycii, goji berry, or wolfberry), as a traditional Chinese herb, was recorded beneficial for longevity in traditional Chinese medical scriptures and currently is a natural dietary supplement worldwide. However, under modern experimental conditions, the longevity effect of L. barbarum berry and the underlying mechanisms have been less studied. Here, we reported that total water extracts of L. barbarum berry (LBE), which contains 22% polysaccharides and other components, such as anthocyanins, extended the lifespan of Caenorhabditis elegans without side effects on worm fertility and pharyngeal pumping. Interestingly, we found that the lifespan extension effect was more prominent in worms with shorter mean lifespan as compared to those with longer mean lifespan. Furthermore, we showed that the lifespan extension effect of LBE depended on deacetylase sir-2.1. Remarkably, LBE rescued heat shock transcription factor-1 (hsf-1) deficiency in wild-type worms with different mean lifespans, and this effect also depended on sir-2.1. In addition, we found that LBE extended lifespan and alleviated toxic protein aggregation in neurodegenerative worms with hsf-1 deficiency. Our study suggested that LBE may be a potential antiaging natural dietary supplement especially to individuals with malnutrition or chronic diseases and a potential therapeutic agent for neurodegenerative diseases characterized by hsf-1 deficiency.

Precision Redox: The Key for Antioxidant Pharmacology.

Significance: The redox balance of cells provides a stable microenvironment for biological macromolecules to perform their physiological functions. As redox imbalance is closely related to the occurrence and development of a variety of diseases, antioxidant therapies are an attractive option. However, redox-based therapeutic strategies have not yet shown satisfactory results. To find the key reason is of great significance. Recent Advances: We emphasize the precise nature of redox regulation and elucidate the importance and necessity of precision redox strategies from three aspects: differences in redox status, differences in redox function, and differences in the effects of redox therapy. We then propose the "5R" principle of precision redox in antioxidant pharmacology: "Right species, Right place, Right time, Right level, and Right target." Critical Issues: Redox status must be considered in the context of species, time, place, level, and target. The function of a biomacromolecule and its cellular signaling role are closely dependent on redox status. Accurate evaluation of redox status and specific interventions are critical for the success of redox treatments. Precision redox is the key for antioxidant pharmacology. The precise application of antioxidants as nutritional supplements is also key to the general health of the population. Future Directions: Future studies to develop more accurate methods for detecting redox status and accurately evaluating the redox state of different physiological and pathological processes are needed. Antioxidant pharmacology should consider the "5R" principle rather than continuing to apply global nonspecific antioxidant treatments. Antioxid. Redox Signal. 34, 1069-1082.

Functional Up-Conversion Nanoparticle-Based Immunochromatography Assay for Simultaneous and Sensitive Detection of Residues of Four Tetracycline Antibiotics in Milk.

An ultrahigh-sensitivity lateral flow immunochromatography (LFIC) assay based on up-converting nanoparticles (UCNPs) was developed to carry out a multi-residue detection of tetracycline in milk. The sensitivity of the immunoassay was greatly improved by the use of a broad-spectrum monoclonal antibody attached to UCNPs to form a signal probe. Under the optimal conditions, the UCNP-LFIC assay enabled sensitive detection of tetracycline (TC) as well as of oxytetracycline (OTC), chlortetracycline (CTC), and doxycycline (DOX) within 10 min, with IC 50 values of 0.32, 0.32, 0.26, 0.22 ng/mL, respectively. There was no cross-reactivity with ten other antibiotics. Similarly, we evaluated the experimental results for matrix effects. Experiments involving spiking showed the four tetracycline antibiotics displaying mean recoveries ranging from 93.95 to 111.90% with relative standard deviations (RSDs) of < 9.95%. The detection results of actual samples using the developed method showed a good correlation (R 2 ≥ 0.98) with the results using high-performance liquid chromatography (HPLC). Thus, the assay can achieve an ultrahighly sensitive detection of antibiotics in milk, and can hence promote human health and provides promising applications in the bio-detection field.

Adaptation of Rice to the Nordic Climate Yields Potential for Rice Cultivation at Most Northerly Site and the Organic Production of Low-Arsenic and High-Protein Rice.

There is an urgent demand for low-arsenic rice in the global market, particularly for consumption by small children. Soils in Uppsala, Sweden, contain low concentrations of arsenic (As). We hypothesize that if certain japonica paddy rice varieties can adapt to the cold climate and long day length in Uppsala and produce normal grains, such a variety could be used for organic production of low-arsenic rice for safe rice consumption. A japonica paddy rice variety, "Heijing 5," can be cultivated in Uppsala, Sweden, after several years' adaptation, provided that the rice plants are kept under a simple plastic cover when the temperature is below 10°C. Uppsala-adapted "Heijing 5" has a low concentration of 0.1 mg per kg and high protein content of 12.6% per dry weight in brown rice grain, meaning that it thus complies with all dietary requirements determined by the EU and other countries for small children. The high protein content is particularly good for small children in terms of nutrition. Theoretically, Uppsala-adapted "Heijing 5" can produce a yield of around 5100 kg per ha, and it has a potential for organic production. In addition, we speculate that cultivation of paddy rice can remove nitrogen and phosphorus from Swedish river water and reduce nutrient loads to the Baltic Sea and associated algae blooms.

Multiplex Recombinase Polymerase Amplification Assay for the Simultaneous Detection of Three Foodborne Pathogens in Seafood.

Foodborne pathogens can cause foodborne illness. In reality, one food sample may carry more than one pathogen. A rapid, sensitive, and multiple target method for bacteria detection is crucial in food safety. For the simultaneous detection of Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella Enteritidis, multi-objective recombinase polymerase amplification (RPA) combined with a lateral flow dipstick (LFD) was developed in this study. The whole process, including amplification and reading, can be completed in 15 min at 37 °C. The detection limits were 2.6 × 101 CFU/mL for Staphylococcus aureus, 7.6 × 101 CFU/mL for Vibrio parahaemolyticus, and 1.29 × 101 CFU/mL for Salmonella Enteritidis. Moreover, colored signal intensities on test lines were measured by a test strip reader to achieve quantitative detection for Staphylococcus aureus (R2 = 0.9903), Vibrio parahaemolyticus (R2 = 0.9928), and Salmonella Enteritidis (R2 = 0.9945). In addition, the method demonstrated good recoveries (92.00%-107.95%) in the testing of spiked food samples. Therefore, the multiplex LFD-RPA assay is a feasible method for the rapid, sensitive, and quantitative detection of bacterial pathogens in seafood.