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Numerous farmers worldwide are impacted by diseases connected to rice leaves that frequently endanger the sustainability of the rice industry. Diseases that affect the leaves of rice plants severely limit their ability to produce rice, and they are typically brought on by bacteria, viruses, or fungi. This paper proposes an innovative classification scheme for rice leaf diseases based on Federated Learning (FL). Here, FL framework comprises two entities, namely nodes and servers. Every node does initial local training using local data. Moreover, produced local model is then updated on server. Model aggregation is done at the server since several nodes update their local models and send them to it. The nodes download the global model that server has generated as a result. The nodes update their training using transferred global model and local model. The following series of actions are taken in the training model. The input image is mainly obtained from a database and pre-processed with a Kalman filter to eliminate noise. Then, numerous operations for data augmentation are applied. In addition, feature extraction is done and generated features are used in LeNet for rice leaf diseases classification. LeNet is trained using the Spotted Hyena Archimedes Optimizer (SHAO). The developed method shows better precision of 91.3%, recall of 92.2%, f-measure of 91.7%, loss function of 3.3%, Mean Square Error (MSE) of 7.3%, and Root MSE of 27.1%. [ABSTRACT FROM AUTHOR]

ObjectivesMethodsResultsConclusionIron (Fe) accumulation and resultant oxidative stress play a significant role in the neuronal death observed in Parkinson’s disease (PD). Brown rice (BR) possesses antioxidant properties able to reduce cellular oxidative damage. Thus, we hypothesized that BR may ameliorate Fe-induced parkinsonism due to oxidative stress.Two – to three-day-old male flies were concurrently exposed to Fe (ferrous sulphate, 1 mM) and interventions, divided into eight groups: control; Fe; BR; white rice (WR); L-dopa (1 mM); Fe (1 mM) + BR; Fe (1 mM) + WR; and Fe (1 mM) + L-dopa (1 mM). The flies were exposed for 15 days to their respective diets, and their behavior, relevant biomarkers, and the expression of related genes were evaluated.Chronic exposure to Fe caused cognitive and locomotor deficits by increasing Fe levels (p = 0.027) in flies’ heads, as well as heightened aggression and grooming episodes (p < 0.001). The elevated iron levels induced changes consistent with oxidative stress, evidenced by increased MDA levels (p < 0.001), and reduced activity of catalase (p < 0.001) and glutathione peroxidase (GPx) (p < 0.001), along with decreased dopamine levels (p < 0.001). Additionally, there was dysregulation in the mRNA expression of malvolio, ferritin, Nrf2, DJ-1, GPx, and catalase (p < 0.05). BR prevented the Fe-induced effects (Fe + BR group) even more effectively than L-Dopa (p < 0.001).The findings indicate that BR has the potential to mitigate Fe-induced ROS-mediated damage in a Drosophila model of PD-like disease by modulating key players in the Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

• Brown Planthopper is a serious threat to rice crop, posing a significant risk to food security. • To combat the damage, molecular breeding stands as an efficient approach by utilizing resistance genes. • Accordingly, a sophisticated marker assisted breeding technique was employed with SSRs and SNPs to introduce BPH genes from M229 and 10–3 donors into susceptible Telangana Sona. • Five backcross lines (BC 1 (a)−14, BC 1 (a)−19, BC 1 (b)−2, BC 1 (b)−4, BC 1 (b)−5) from both the crosses were identified as potential materials, displaying grain characteristics similar to Telangana Sona. Brown Planthopper (BPH) is one of the most destructive insect pests of rice that threatens food security. Molecular breeding through the use of resistance genes per se would be an economic and efficient way to combat the damage caused by BPH. Telangana Sona (TS) is an elite, popular and a high yielding rice variety susceptible to the infestation of BPH causing severe yield losses. In the current investigation, a marker-assisted backcross breeding approach using gene-specific Simple Sequence Repeats (SSRs) and designed Single Nucleotide Polymorphisms (SNPs) was employed to incorporate BPH resistance genes from the donor lines, M229 and 10–3 into TS. Foreground selection using gene-specific SSRs pinned down one plant (BC 1 (a)-19) from TS//TS/M229 cross with qBph-3–1 and Bph33(t) genes/QTLs, while, six plants of TS//TS/10–3 cross had Bph33(t) gene. Validation of BC 1 F 1 plants with designed SNPs altogether identified three (BC 1 (a)-14, BC 1 (a)-18, BC 1 (a)-19) from TS//TS/M229 and three lines (BC 1 (b)-2, BC 1 (b)-4, BC 1 (b)-5) from TS//TS/10–3 cross positive for snpOS00915, snpOS00922 and snpOS00923. All these lines were also found to be phenotypically resistant to BPH as screened using a modified mass tiller screening method. Altogether, foreground selection coupled with stringent phenotypic selection and agro-morphological evaluation led to the identification of two backcross lines (BC 1 (a)-14 and BC 1 (a)-19) from TS//TS/M229 and three (BC 1 (b)-2, BC 1 (b)-4, BC 1 (b)-5) from TS//TS/10–3 that had grain type characteristics similar to TS that can be potentially used as breeding material for further backcrossing and advancing for near isogenic lines development. The study demonstrates the potential efficacy of marker-assisted selection deployed with both SSRs and SNPs that can be employed in breeding for BPH-resistant varieties. [ABSTRACT FROM AUTHOR]

Asian rice gall midge is one of the important pests of rice, which attacks the crop from nursery to the end of the tillering stage. Managing this pest through plant resistance is the most viable and economical. Two hundred‐two rice genotypes were phenotyped against Asian rice gall midge, Orseolia oryzae (Wood‐Mason) and the mechanism of resistance in terms of antixenosis and antibiosis was studied. Antixenosis mechanism for adult settlement and egg laying indicated that the susceptible genotypes were preferred more than the resistant genotypes in a free choice test. First instar maggots were found and did not continue their growth on resistant genotypes further. However, in susceptible genotypes, they molted successfully and emerged as adults. No choice tests revealed that the emergence of adults in susceptible genotypes took less time than in resistant genotypes. Higher adult sex ratio was found in susceptible genotypes. Estimation of biochemical components in rice shoot apices of selected genotypes revealed that higher levels of total phenols, wax content, total flavonoids and total free amino acids were present in the resistant genotypes. Still, the number of total sugars, reducing sugars and total protein contents were significantly higher in the susceptible genotypes. Hence, the resistance mechanism in rice gall midge was displayed as a combination of antixenosis and antibiosis mechanism. The output of the study would be helpful in breeding for rice varieties resistant to Asian rice gall midge. [ABSTRACT FROM AUTHOR]

SUMMARY: Bacterial leaf streak (BLS), caused by Xanthomonas oryzae pv. oryzicola (Xoc), is a major bacterial disease in rice. Transcription activator‐like effectors (TALEs) from Xanthomonas can induce host susceptibility (S) genes and facilitate infection. However, knowledge of the function of Xoc TALEs in promoting bacterial virulence is limited. In this study, we demonstrated the importance of Tal10a for the full virulence of Xoc. Through computational prediction and gene expression analysis, we identified the hexokinase gene OsHXK5 as a host target of Tal10a. Tal10a directly binds to the gene promoter region and activates the expression of OsHXK5. CRISPR/Cas9‐mediated gene editing in the effector binding element (EBE) of OsHXK5 significantly increases rice resistance to Xoc, while OsHXK5 overexpression enhances the susceptibility of rice plants and impairs rice defense responses. Moreover, simultaneous editing of the promoters of OsSULTR3;6 and OsHXK5 confers robust resistance to Xoc in rice. Taken together, our findings highlight the role of Tal10a in targeting OsHXK5 to promote infection and suggest that OsHXK5 represents a potential target for engineering rice resistance to Xoc. [ABSTRACT FROM AUTHOR]

In Asian countries, rice is the major agricultural product. Hence, the initial identification of plant disorder via the IoT (Internet of Things) offers to ignore the rice from critical disorders. To increase crop production, the measurements should be considered to completely destroy the rice plant disorders by an effective system. This paper proposed an Intelligent IoT-aided deep learning model for detecting rice blast fungal along with a hybrid heuristic algorithm. The proposed work encompasses with multiple stages that are explained as follows. At first, the required paddy images are gathered from online data resources. Next, the pre-processing of the collected images is made by adaptive mean filtering and contrast enhancement. Further, the adaptive thresholding and morphological operation are adopted for leaf segmentation purposes, where the threshold value is tuned by a Fitness-based Billiards-inspired Rat Swarm Optimizer (FBRSO). Consequently, from the segmented image, the Region of Interest (ROI) is cropped. Finally, the cropped ROI is subjected to the Optimized MobileNetv2 and Multiscale Residual Attention Network (OMMRAN), where it includes MobileNetV2 and Multiscale Residual Attention Network, in which some of the hyperparameters are tuned by FBRSO approach. The performance is validated and compared with other existing approaches for detecting rice diseases effectively. [ABSTRACT FROM AUTHOR]

• Spider community composition changed during the rice growing season. • The rice field development generally decreased the number of horizontal web-building spiders and captured detritivorous prey. • Species identity and species traits of spider as well as environmental factors affect prey capture by web-building spiders. Understanding the effects of microhabitat changes on arthropod predator communities and their prey in agroecosystems is essential for field management and biocontrol. Few studies have investigated the trait composition of web-building spider communities in rice ecosystems. Here, we examined how temporal changes during the rice field development affect the abundance and traits of orb-web spiders, and how these effects consequently influence captured prey number and prey composition in irrigated rice ecosystems in southern Thailand. We used structural equation models to evaluate direct and indirect, spider-mediated effects of rice field development on captured prey numbers in each different guild. We found that the number of horizontal web-building spiders decreased during the rice field development, whereas there was no significant change in number of vertical web-building spiders. The number of captured detritivorous insects was positively related to the numbers of horizontal and vertical web-building spiders, while phytophagous insects and others were positively related only to the numbers of vertical web-building spiders. Moreover, the prey number captured by vertical web-building spiders seems to be indirectly increased through the decreasing number of horizontal web-building spiders in the late rice season. A fourth-corner analysis showed that spider species identity, spider traits (web type, web height and web diameter), vegetation height, and water level generally influenced the prey captured by web-building spiders. Horizontal web-building spider species with lower web placement during the flooding phase captured high numbers of detritus-feeding insects, while vertical web-building spider species with higher web placement captured high numbers of rice pests, predators and others. Our results suggest that the field development acted as an environmental factor that determined the species identity and traits of web-building spider communities. The findings of this study can help to predict the ecosystem services provided by the web-building spider community in rice ecosystems. [ABSTRACT FROM AUTHOR]

BACKGROUND: The brown planthopper (BPH), Nilaparvata lugens, is one of the most destructive pests of rice. Owing to the rapid adaptation of BPH to many pesticides and resistant varieties, identifying putative gene targets for developing RNA interference (RNAi)‐based pest management strategies has received much attention for this pest. The glucoprotein papilin is the most abundant component in the basement membranes of many organisms, and its function is closely linked to development. RESULTS: In this study, we identified a papilin homologous gene in BPH (NlPpn). Quantitative Real‐time PCR analysis showed that the transcript of NlPpn was highly accumulated in the egg stage. RNAi of NlPpn in newly emerged BPH females caused nonhatching phenotypes of their eggs, which may be a consequence of the maldevelopment of their embryos. Moreover, the transcriptomic analysis identified 583 differentially expressed genes between eggs from the dsGFP‐ and dsNlPpn‐treated insects. Among them, the 'structural constituent of cuticle' cluster ranked first among the top 15 enriched GO terms. Consistently, ultrastructural analysis unveiled that dsNlPpn‐treated eggs displayed a discrete and distorted serosal endocuticle lamellar structure. Furthermore, the hatchability of BPH eggs was also successfully reduced by the topical application of NlPpn‐dsRNA‐layered double hydroxide nanosheets onto the adults. CONCLUSION: Our findings demonstrate that NlPpn is essential to maintaining the regular structure of the serosal cuticle and the embryonic development in BPH, indicating NlPpn could be a potential target for pest control during the egg stage. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The use of unmanned aerial vehicles (UAVs) for the application of plant protection products (PPPs) in paddy fields is becoming increasingly prevalent worldwide. Despite its growing usage, UAV spraying for rice pest control faces practical challenges, including limited canopy penetration, uneven deposition, and significant spray drift. This study investigated the impact of two tank‐mix adjuvants, Wonderful Rosin (Adjuvant‐1) and Tiandun (Adjuvant‐2), at six volume concentrations, on the spray liquid's physicochemical properties, spray drift, plant deposition, and the biological efficacy of rice insecticides using a quadrotor UAV sprayer. RESULTS: The physicochemical characteristics of the spray liquid influenced spray performance and biological efficacy. Incorporating Adjuvant‐1 and Adjuvant‐2 led to a decrease in surface tension and contact angle while increasing the viscosity of the spray solution. These alterations in surface tension and viscosity contributed to an optimized droplet size distribution, reduced spray drift, enhanced deposition uniformity and penetration, and improved control efficacy against the rice planthopper in UAV applications. The highest control efficacy was observed at a concentration of 0.5%, showing an improvement of 35.12% (Adjuvant‐1) and 20.23% (Adjuvant‐2) over applications without tank‐mix adjuvant 7 days after treatment. CONCLUSION: The judicious selection of tank‐mix adjuvants for UAV PPP applications can significantly enhance spray performance and biological efficacy in controlling rice insects. This study's findings offer valuable insights for integrating tank‐mix adjuvants into UAV spraying applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In warm and humid regions, the productivity of sorghum is significantly limited by the fungal hemibiotrophic pathogen Colletotrichum sublineola, the causal agent of anthracnose, a problematic disease of sorghum (Sorghum bicolor (L.) Moench) that can result in grain and biomass yield losses of up to 50%. Despite available genomic resources of both the host and fungal pathogen, the molecular basis of sorghum-C. sublineola interactions are poorly understood. By employing a dual-RNA sequencing approach, the molecular crosstalk between sorghum and C. sublineola can be elucidated. In this study, we examined the transcriptomes of four resistant sorghum accessions from the sorghum association panel (SAP) at varying time points post-infection with C. sublineola. Approximately 0.3% and 93% of the reads mapped to the genomes of C. sublineola and Sorghum bicolor, respectively. Expression profiling of in vitro versus in planta C. sublineola at 1-, 3-, and 5-days post-infection (dpi) indicated that genes encoding secreted candidate effectors, carbohydrate-active enzymes (CAZymes), and membrane transporters increased in expression during the transition from the biotrophic to the necrotrophic phase (3 dpi). The hallmark of the pathogen-associated molecular pattern (PAMP)-triggered immunity in sorghum includes the production of reactive oxygen species (ROS) and phytoalexins. The majority of effector candidates secreted by C. sublineola were predicted to be localized in the host apoplast, where they could interfere with the PAMP-triggered immunity response, specifically in the host ROS signaling pathway. The genes encoding critical molecular factors influencing pathogenicity identified in this study are a useful resource for subsequent genetic experiments aimed at validating their contributions to pathogen virulence. This comprehensive study not only provides a better understanding of the biology of C. sublineola but also supports the long-term goal of developing resistant sorghum cultivars. [ABSTRACT FROM AUTHOR]

The planthopper Nilaparvata muiri is a sister species to N. lugens (Hemiptera: Delphacidae), a notorious insect pest in Asian rice fields. N. muiri and N. lugens have a different host preference despite the similarities in many biological features. To better understand the adaptive evolution of planthoppers, comprehensive genomic information on N. muiri and N. lugens are urgently needed. In this study, we used ultra-low input PacBio HiFi libraries and Hi-C sequencing technologies to assemble a reference genome of a single N. muiri at the chromosomal level. The genome size was determined to be 531.62 Mb with a contig N50 size of 2.47 Mb and scaffold N50 size of 38.37 Mb. Totally, 96.61% assembled sequences were anchored to the 15 pseudo-chromosomes. BUSCO analysis yielded an Insecta completeness score of 98.6%. A total of 22,057 protein-coding genes were annotated, and 168.16 Mb repetitive sequences occupying 31.63% of genome were pinpointed. The assembled genome is valuable for evolutionary and genetic studies of planthoppers, and may provide sights to pest control. [ABSTRACT FROM AUTHOR]

Tomato disease image recognition plays a crucial role in agricultural production. Today, whilemachine vision methods based on deep learning have achieved some success indiseaserecognition, theystill faceseveralchallenges. These include issues such as imbalanced datasets, unclear disease features, small inter-class differences, and large intra-class variations. To address these challenges, this paper proposes a method for classifying and recognizing tomato leaf diseases based on machine vision. First, to enhance the disease feature details in images, a piecewise linear transformation method is used for image enhancement, and oversampling is employed to expand the dataset, compensating for the imbalanced dataset. Next, this paper introduces a convolutional block with a dual attention mechanismcalled DAC Block, which is used to construct a lightweight model named LDAMNet. The DAC Block innovatively uses Hybrid Channel Attention (HCA) and Coordinate Attention (CSA) to process channel information and spatial information of input images respectively, enhancing the model's feature extraction capabilities. Additionally, this paper proposes a Robust Cross-Entropy (RCE) loss function that is robust tonoisylabels, aimedat reducing the impact of noisy labels on the LDAM Net model during training. Experimental results show that this method achieves an average recognition accuracy of 98.71% on the tomato disease dataset, effectively retaining disease information in images and capturing disease areas. Furthermore, the method also demonstrates strong recognition capabilities on rice crop disease datasets, indicating good generalization performance and the ability to function effectively in disease recognition across different crops. The research findings of this paper provide new ideas and methods for the field of crop disease recognition. However, future research needs to further optimize the model's structure and computational efficiency, and validate its application effects in more practical scenarios. [ABSTRACT FROM AUTHOR]

Fermented products contain probiotic organisms that have beneficial and therapeutic effects on the gastrointestinal tract. The main objective of the study is to isolate probiotic bacteria from fermented sour traditional rice water and to evaluate their probiotic activity. The microbes were isolated from the fermented rice water and the characterization of the organisms was determined using MALDI-TOF MS. The morphological analysis, biochemical test, and carbohydrate fermentation test were done for further characterization. The colonization and therapeutic properties of organisms were evaluated by performing in vitro simulation studies. The results indicated that the isolated gram-positive organisms Pediococcus pentosaecus and Lactococcus lactis from traditional fermented sour rice water possessed desirable in vitro probiotic properties. Consuming fermented sour rice water enriches intestinal flora with beneficial bacteria and enzymes. Fermented rice water improves gut microbiome health, immune system function, and is also used to treat chronic conditions. [ABSTRACT FROM AUTHOR]

Brown planthopper (BPH), Nilaparvata lugens (Stal) is a monophagous and one of most devastating pest of rice. Application of insecticides is inevitable to control the infestation of BPH on rice crops. However, the indiscriminate use of various insecticides in rice is leading to pest resurgence. Several factors have been connected to the resurgence of brown planthoppers, especially the reduction in natural enemies and changes in plant nutrition after insecticide application. Hence, in the present study, we studied the resurgence of BPH post application of different insecticides in rice and assessed the impact of insecticides on natural enemy population during Rabi 2022-23. Among nine insecticides tested, two insecticides viz., deltamethrin 11 EC @ 15 g a.i/ha (44.70%) and imidacloprid 17.8 SL @ 25 g a.i/ha (23.01%) significantly increased the population of N. lugens over untreated check and consequently resulted in higher BPH resurgence. A greater reduction in predatory mirid bugs and spiders was observed in the deltamethrin and imidacloprid treated groups compared to the untreated check. In conclusion, we found that deltamethrin and imidacloprid induce the BPH resurgence in rice compared to other tested insecticides and the observed resurgence was partly due to the reduction of natural enemies. [ABSTRACT FROM AUTHOR]

A study published in the journal iMeta examines the role of beneficial microbes in protecting rice plants from fungal pathogens. The researchers found that certain microbes in the rice plants' microbiome can directly suppress fungal infections. They created a simplified community of three beneficial bacteria, which was shown to enhance rice resistance against fungal pathogens in both lab and field conditions. The study suggests that these beneficial microbes could be used as biocontrol agents to improve rice productivity and manage plant diseases in a cost-effective way. [Extracted from the article]

RD6, the most popular glutinous rice in Thailand, is high in quality but susceptible to blast and bacterial blight disease. It was thus improved for disease resistance through marker-assisted backcross selection (MAS). The objective of this study was to evaluate the performance of improved near isogenic lines. Eight RD6 rice near isogenic lines (NILs) derived from MAS were selected for evaluation with RD6, a standard susceptible check variety, as well as recurrent parent for a total of nine genotypes. The experiment was conducted during the wet season under six environments at three locations, Khon Kaen, Nong Khai, and Roi Et, which was repeated at two years from 2019 to 2020. Nine genotypes, including eight RD6 rice near isogenic lines (NILs) selected from two in-tandem breeding programs and the standard check variety RD6, were evaluated to select the high-performance new improved lines. The first group, including four NILs G1–G4, was gene pyramiding of blast and BB resistance genes, and the second group, including another four NILs G5–G8, was gene pyramiding of blast resistance and salt tolerance genes. Field disease screening was observed for all environments. Two disease occurrences, blast (leaf blast) and bacterial blight, were found during the rainy season of all environments. The NILs containing blast resistance genes were excellent in gene expression. On the other hand, the improved lines containing the xa5 gene were not highly resistant under the severe stress of bacterial blight (Nong Khai 2020). Notwithstanding, G2 was greater among the NILs for yield maintenance than the other genotypes. The agronomic traits of most NILs were the same as RD6. Interestingly, the traits of G2 were different in plant type from RD6, specifically photosensitivity and plant height. Promising rice RD6 NILs with high yield stability, good agronomic traits, and disease resistance were identified in the genotypes G1, G2, and G7. The high yield stability G1 and G7 are recommended for widespread use in rain-fed areas. The G2 is specifically recommended for use in the bacterial blight (BB) disease prone areas. [ABSTRACT FROM AUTHOR]

In Asia, rice is the most consumed grain by humans, serving as a staple food in India. The yield of rice paddies is easily affected by nutrient deficiencies and leaf diseases. To overcome this problem and improve the yield productivity of rice, nutrient deficiency and leaf disease identification are essential. The main nutrient elements in paddies are potassium, phosphorus, and nitrogen (PPN), the deficiency of any of which strongly affects the rice plants. When multiple nutrient elements are deficient, the leaf color of the rice plants is altered. To overcome this problem, optimal nutrient delivery is required. Hence, the present study proposes the use of Fuzzy C Means clustering (FCM) with Improved Tunicate Swarm Optimization (ITSO) to segment the lesions in rice plant leaves and identify the deficient nutrients. The proposed ITSO integrates the Tunicate Swarm Optimization (TSO) and Bacterial Foraging Optimization (BFO) approaches. The Hybrid Convolutional Neural Network (HCNN), a deep learning model, is used with ITSO to classify the rice leaf diseases, as well as nutrient deficiencies in the leaves. Two datasets, namely, a field work dataset and a Kaggle dataset, were used for the present study. The proposed HCNN-ITSO classified Bacterial Leaf Bright (BLB), Narrow Brown Leaf Spot (NBLS), Sheath Rot (SR), Brown Spot (BS), and Leaf Smut (LS) in the field work dataset. Furthermore, the potassium-, phosphorus-, and nitrogen-deficiency-presenting leaves were classified using the proposed HCNN-ITSO in the Kaggle dataset. The MATLAB platform was used for experimental analysis in the field work and Kaggle datasets in terms of various performance measures. When compared to previous methods, the proposed method achieved the best accuracies of 98.8% and 99.01% in the field work and Kaggle datasets, respectively. [ABSTRACT FROM AUTHOR]

Rice bakanae disease (RBD) is a typical seed-borne fungal disease caused by Fusarium fujikuroi. Prochloraz is a sterol demethylation inhibitor, which is among the most important classes of active ingredients for the management of RBD. In 2022, the total resistance frequency of F. fujikuroi to prochloraz in Zhejiang Province was 62.67%. The fitness of the prochloraz-resistant population was lower than that of the susceptible population, but its pathogenicity was slightly stronger. The S312T and F511S double mutations of Ffcyp51b were detected in the resistant isolates. Loop-mediated isothermal amplification (LAMP) technology based on S312T was established to rapidly determine prochloraz resistance in F. fujikuroi. LAMP primer mismatch design was performed based on the cyp51b gene, and 100–300 bp sequences containing a mutation at codon 312 were amplified. In a 25 µL reaction tube, 1 pg/µL DNA of F. fujikuroi could be detected. The detection limit for the frequency of prochloraz resistance was 0.498% using this method. We performed LAMP detection on rice seedlings inoculated with prochloraz-sensitive and -resistant isolates and treated them with prochloraz. Prochloraz demonstrated good control in rice seedlings. A chromogenic reaction was observed in seedlings treated with prochloraz-resistant isolates, and the results were verified using electrophoresis. It has been demonstrated that LAMP technology based on the S312T genotype can quickly and specifically detect prochloraz-resistant isolates in rice seedlings. [ABSTRACT FROM AUTHOR]

Sheath rot and dirty panicle are some of the major diseases of rice in Thailand. The diseases are traditionally considered to be caused by the pathogen Sarocladium oryzae and damage and lower both the quantity and quality of rice grain. In this study, 32 fungal isolates collected from the central and northeastern regions of Thailand were analysed phylogenetically using three molecular markers (ITS, D1/D2 of 28S rDNA and ACT) and physiological races were determined on 10 differential rice cultivars. We found that S. oryzae is not the only causal agent of sheath rot in Thailand, but S. attenuatum was also found. Despite having similar morphological features, the phylogenetic analysis recognised 11 of 32 isolates as S. attenuatum and the remaining isolates as S. oryzae. This is the first report of S. attenuatum causing sheath rot of rice in Thailand in addition to S. oryzae. Evaluation of physiological races revealed high pathogenic diversity of the two species. Thus, 16 and 11 physiological races were recorded from 21 isolates of S. oryzae and 11 isolates of S. attenuatum, respectively. These results indicate that both S. oryzae and S. attenuatum are the causal agents of rice sheath rot and dirty panicle in Thailand and that they are pathologically diverse. [ABSTRACT FROM AUTHOR]

Summary: The clade III subfamily of OsSWEETs includes transmembrane proteins necessary for susceptibility to bacterial blight (BB). These genes are targeted by the specific transcription activator‐like effector (TALE) of Xanthomonas oryzae pv. oryzae and mediate sucrose efflux for bacterial proliferation. However, the mechanism through which OsSWEETs regulate rice immunity has not been fully elucidated. Here, we demonstrated that the cytosolic carboxyl terminus of OsSWEET11a/Xa13 is required for complementing susceptibility to PXO99 in IRBB13 (xa13/xa13). Interestingly, the C‐terminus of ZmXa13, the maize homologue of OsSWEET11a/Xa13, could perfectly substitute for the C‐terminus of OsSWEET11a/Xa13. Furthermore, OsSWEET11a/Xa13 interacted with the high‐mobility group B1 (OsHMGB1) protein and the small heat shock‐like protein OsHsp20L through the same regions in the C‐terminus. Consistent with the physical interactions, knockdown or knockout of either OsHMGB1 or OsHsp20L caused an enhanced PXO99‐resistant phenotype similar to that of OsSWEET11a/OsXa13. Surprisingly, the plants in which OsHMGB1 or OsHsp20L was repressed developed increased resistance to PXO86, PXO61 and YN24, which carry TALEs targeting OsSWEET14/Xa41 or OsSWEET11a/Xa13. Additionally, OsHsp20L can interact with all six members of clade III OsSWEETs, whereas OsHMGB1 can interact with five other members in addition to OsSWEET12. Overall, we revealed that OsHMGB1 and OsHsp20L mediate conserved BB susceptibility by interacting with clade III OsSWEETs, which are candidates for breeding broad‐spectrum disease‐resistant rice. [ABSTRACT FROM AUTHOR]

Simple Summary: We exposed brown planthoppers (BPHs) Nilaparvata lugens to the entomopathogenic fungus Cordyceps javanica PSUC002 and observed morpho-histological changes from 0 to 120 h post-inoculation (pi). At 12 h pi, we observed the first filamentous fungi on the external integument and the first fungal conidia penetrated host planthopper cells at 24 h pi. In contrast, we observed the initial degeneration of BPHs at 6 h pi, especially in the integument and adipose tissue. We also found the degeneration of integument and adipose tissue at 12 h pi, and their completed necrosis became clear at 96 h pi. This study illustrated the process of C. javanica infection in BPHs and demonstrated that fungal agents can be used to control the BPHs in an integrated pest management (IPM) program. The brown planthopper (BPH), Nilaparvata lugens (Stål, 1854), is a pest of rice plants worldwide. Cordyceps javanica is a destructive entomopathogenic fungus known to attack leafhoppers or BPHs specifically. Live adult BPH samples were inoculated with isolated C. javanica PSUC002, and their interaction was morpho-histologically examined from 0 to 120 h post-inoculation (pi). We observed that the mortality of BPH continuously increased until 120 h pi (Day 5). Tissue alterations in the host were examined after infection using morphological and histological methods, including the Grocott Methenamine Silver stain test (GMS). Filamentous fungi were first found on the external integument at 12 h pi, and fungal conidia attached to the integument at 24 h pi. However, the initial degeneration of BPHs was identified by histology at 6 h pi especially in the integument and adipose tissue. We identified the degeneration and loss of integument and adipose tissue of infected BPHs at 12 h pi, and their necrosis was completed at 96 h pi. The enzymatic index of the sampled fungi (chitinase and protease) peaked at 7 days of incubation. This study demonstrated that C. javanica PSUC002 is useful to control the BPHs as an eco-friendly practice and will possibly be applied in agriculture. [ABSTRACT FROM AUTHOR]

Temporal change in vegetation complexity and field management may interactively affect the structure of predator–prey networks in agroecosystems and consequently alter the biocontrol potential of predators. There is a limited number of studies that have addressed these questions for generalist predator–prey networks.We investigated how vegetation complexity during crop development and management type (conventional vs. organic) affect the trophic networks of orb‐weaving spiders and their prey in rainfed lowland rice ecosystems in southern Thailand. Specifically, we investigated orb‐weaving spiders and prey composition, prey selectivity and network structure.Overall, orb‐weaving spiders captured mostly detritus‐associated Diptera, aquatic‐associated Ephemeroptera and Hemiptera pests. The increasing vegetation complexity during rice development significantly restructured the network of orb‐weaving spiders and prey, while field management had only a marginal effect. The increased vegetation complexity during rice development led to an increased number of weak trophic interactions in comparison to few but strong interactions in simple vegetation.Our results indicate that increasing the number of spider species per prey taxon (prey vulnerability) in late rice season may enhance their top‐down control of prey including rice pests. This study also highlights that the network complexity and the stability of rice ecosystems increased during the rice growing season as the vegetation became more complex.Future practices could look for a way to support the densities of detritus and aquatic insects and to artificially increase habitat complexity during the early stage of rice development to improve the biocontrol services provided by the orb‐weaving spiders. [ABSTRACT FROM AUTHOR]

The identification and classification of pests in rice field are the prerequisites of early warning systems for pest dis-asters. Among these pests, the rice planthoppers cause the most serious damage. However, the existing deep learning models for rice planthopper recognition are characterized by large size and numerous parameters, which makes them unsuitable for the deployment on embedded devices with limited computational resources. To address this issue, a lightweight rice planthopper recognition model based on YOLOv5 is proposed in this paper. In the model, a lightweight convolutional network named GhostNet is employed as the backbone to reduce the operational parameters. Additionally, a convolutional attention module (CBAM) is integrated into the backbone network to effectively enhance the transmission of deep information, so as to improve the model's ability of recognizing rice planthopper images. The original CIoU loss function is replaced by the SIoU loss function to expedite model convergence. Experimental results demonstrate that the modified model achieves the mAP@0.5 as 82.8%, with the parameter count of 3.12x106 and the model size of 7.2MB. Compared to the original model, it is a reduction of 46.7% in size and 43.3% in parameters, with a minor accuracy loss of 0.1%. Clearly, the improved model can achieve lightweight characteristics and robust performance, and thus it provides a theoretical and practical foundation for early warning systems against rice planthopper infestations in rice fields. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bacterial virulence factors are involved in various biological processes and mediate persistent bacterial infections. Focusing on virulence factors of phytopathogenic bacteria is an attractive strategy and crucial direction in pesticide discovery to prevent invasive and persistent bacterial infection. Hence, discovery and development of novel agrochemicals with high activity, low‐risk, and potent anti‐virulence is urgently needed to control plant bacterial diseases. RESULTS: A series of novel β‐hydroxy pyridinium cation decorated pterostilbene derivatives were prepared and their antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) were systematacially assessed. Among these pterostilbene derivatives, compound 4S exhibited the best antibacterial activity against Xoo in vitro, with an half maximal effective concentration (EC50) value of 0.28 μg mL−1. A series of biochemical assays including scanning electron microscopy, crystal violet staining, and analysis of biofilm formation, swimming motility, and related virulence factor gene expression levels demonstrated that compound 4S could function as a new anti‐virulence factor inhibitor by interfering with the bacterial infection process. Furthermore, the pot experiments provided convinced evidence that compound 4S had the high control efficacy (curative activity: 71.4%, protective activity: 72.6%), and could be used to effectively manage rice bacterial leaf blight in vivo. CONCLUSION: Compounds 4S is an attractive virulence factor inhibitor with potential for application in treating plant bacterial diseases by suppressing production of several virulence factors. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study compares the food-production efficiencies of integrated rice-fish farming and rice monoculture and evaluates how these farming systems contribute to sustainable food production in the Mekong Delta. The study explores how food-production efficiencies are influenced by the systems' ecological connectivity by comparing more integrated systems that apply integrated rice-fish farming and integrated pest management (IPM) with less integrated systems farming only rice. Rice-fish farmers with plenty of fish had significantly higher rice yields than farmers with less or no fish, especially during the second crop when the rice was grown together with the fish. A positive correlation between the fish and rice yields, indicated synergistic effects between the fish and rice, due to strengthened ecological connectivity and trophic interactions within the rice-field ecosystem. Overall, rice-fish farmers had higher rice yields than rice farmers, despite using lower amounts of fertilizers and pesticides. They also had lower rice production costs compared to rice farmers, partly because the fish helped fertilize the rice and control rice pests. They had a significantly higher profit and benefit cost ratio than rice farmers because of lower production costs, and high rice and fish yields. The results indicate that food-production efficiencies in the Mekong Delta can be enhanced through diversification and increased ecological connectivity, leading to a more efficient use of rice field ecosystem services that support a long-term and healthy production of food. [ABSTRACT FROM AUTHOR]

Small non-coding RNAs (sRNAs) act as post-transcriptional regulators to participate in many cellular processes. Among these, sRNA trans217 has been identified as a key virulent factor associated with pathogenicity in rice, triggering hypersensitive reactions in non-host tobacco and facilitating the secretion of the PthXo1 effector in Xanthomonas oryzae pv. oryzae (Xoo) strain PXO99A. Elucidating potential targets and downstream regulatory genes is crucial for understanding cellular networks governing pathogenicity and plant resistance. To explore the targets regulated by sRNA trans217, transcriptome sequencing was carried out to assess differential expression genes (DEGs) between the wild-type strain PXO99A and a mutant lacking the sRNA fragment under both virulence-inducing or normal growth conditions. DEG analysis revealed that sRNA trans217 was responsible for diverse functions, such as type III secretion system (T3SS), glutamate synthase activity, and oxidative stress response. Three genes were selected for further investigation due to their significant differential expression and biological relevance. Deletion of PXO_RS08490 attenuated the pathogenicity of Xoo in rice and reduced the tolerance level of PXO99A to hydrogen peroxide. These findings suggest a regulatory role of sRNA trans217 in modulating bacterial virulence through multiple gene targets, either directly or indirectly. [ABSTRACT FROM AUTHOR]

Brown spot (BS) disease causes significant losses to rice productivity. In this study, a roving survey in the Karnataka state of India revealed a wider distribution of BS with a percent disease index range of 20.56–50.74. From the symptomatic geo-distinct samples, pure cultures of 63 isolates were obtained. Based on the conidial morphology, 63 isolates were identified as Bipolaris oryzae (Bo) (n = 40), Curvularia lunata (Cl) (n = 15), and Exserohilum rostratum (Er) (n = 08). The taxonomic identity was further confirmed via ITS-sequencing. A pathogenicity assay on a BS-susceptible rice cultivar GNV-05–01 confirmed the pathogenicity of all three pathogens, which induces typical BS disease on test plants. Further, on PDA media, all isolates of three pathogens showed significant cultural diversity for mycelial color, colony type, and sporulation. We further studied the in-planta distribution of three pathogens on a randomly collected 600 BS spots from 10 different rice fields, which indicated that 77.83%, 17.33%, and 4.83% of the typical BS were produced by Bo, Cl, and Er, respectively. The ITS region was sequenced for selected 9, 7, and 3 isolates of Bo, Cl, and Er, respectively, and analyzed for their nucleotide and haplotype diversity, and phylogenetic relationships. A phylogenetic study identified the unique clustering patterns, and haplotyping indicated 3, 4, and 6 haplotypes. Tajima's D (D) test showed several rare alleles in the ITS regions. This is the first comprehensive study reporting the three fungal pathogens causing BS of rice and it is useful for re-designing the screening protocol for the host plant resistance breeding program. [ABSTRACT FROM AUTHOR]

Objectives: Rice (Oryza sativa) is the most important food for more than two thirds of the world's population. Bangladesh is the third largest producer and consumer of rice globally. Recently, several symptoms of Bacterial Panicle Blight (BPB) in rice, including seedling blight, sheath rot, floret sterility, and spotted grains, have been detected in the country. In addition, the presence of the most prevalent and virulent causative agent of BPB, Burkholderia glumae, has been confirmed in rice displaying symptoms of the disease. BPB could become one of the next emerging diseases of rice in Bangladesh, and a complete genome of a B. glumae strain from the country will help clarify its origin and devise proper management systems to continue sustainable rice production. Data description: We report the first complete genome sequence of a B. glumae strain (BD_21g) isolated from symptomatic rice grains in Bangladesh (Natore District). The genome contains 2 chromosomes (1 and 2, with 3,417,499 and 3,855,283 bp, respectively) and 4 plasmids (1-4, with 123,248, 46,628, 88,744 and 53,064 bp, respectively). [ABSTRACT FROM AUTHOR]

Introduction: Akirin as a highly conserved transcription factor, exerts a profound influence on the growth, development, immune response, and reproductive processes in animals. The brown planthopper (BPH), Nilaparvata lugens, a major pest in rice production in Asia, possesses high reproductive capacity, a critical factor contributing to reduced rice yields. The aims of this study were to demonstrate the regulatory role of Akirin in the reproduction of BPH. Methods: In this study, quantitative PCR (qPCR) was used to detect the mRNA expression of genes. RNA interference (RNAi) was used to downregulate the expression of Akirin gene, and RNA sequencing (RNA-seq) was used to screen for differentially expressed genes caused by Akirin downregulation. Hormone contents were measured with the enzyme linked immunosorbent assay (ELISA), and protein content was evaluated with the bicinchoninic acid (BCA) method. Results: Using BPH genome data, we screened for an Akirin gene (NlAkirin). An analysis of tissue-specific expressions showed that NlAkirin was expressed in all tissues tested in female BPH, but its expression level was highest in the ovary. After inhibiting the mRNA expression of NlAkirin in BPH females, the number of eggs laid, hatching rate, and number of ovarioles decreased. Transcriptome sequencing was performed, following a NlAkirin double-stranded RNA treatment. Compared with the genes of the control, which was injected with GFP double-stranded RNA, there were 438 upregulated genes and 1012 downregulated genes; the expression of vitellogenin (Vg) and vitellogenin receptor (VgR) genes as well as the mRNA expression of genes related to the target of rapamycin (TOR), juvenile hormone (JH), and insulin pathways involved in Vg synthesis was significantly downregulated. As a result of NlAkirin knockdown, the titers of JH III and Ecdysone (Ecd) were downregulated in unmated females but returned to normal levels in mated females. The ovarian protein contents in both unmated and mated females were downregulated. Discussion and conclusion: Our results suggest that NlAkirin affects female BPH reproduction by regulating the mRNA expression of genes related to the Vg, VgR, TOR, JH, and insulin signaling pathways, in addition to the titers of JH III and Ecd. The findings of this research provide novel insights into the regulatory role of Akirin in insect reproductive capacity. [ABSTRACT FROM AUTHOR]

Fusarium fujikuroi, the causal agent of rice bakanae disease (RBD), contains five succinate dehydrogenase (Sdh) subunits: FfSdhA, FfSdhB, FfSdhC1, FfSdhC2, and FfSdhD. However, the role of these subunits in regulating sensitivity to succinate dehydrogenase inhibitors (SDHIs) is largely unknown. Here, we conducted targeted gene disruption and phenotypic assays for all Sdh subunits and found that the deletion mutants of FfSdhA, FfSdhB, and FfSdhD exhibited severe defects in hyphal growth, conidiation, virulence, and sensitivity to CaCl2 and oxidative stresses. To a lesser extent, the mycelial growth rate and conidial production of ΔFfSdhC1 were also decreased as compared to those of the wild-type strain JS16. In addition, fungicide sensitivity assays showed that deletion of FfSdhA, B, C1, or D led to decreased sensitivity to all SDHIs tested. Unexpectedly, we were unable to obtain a FfSdhC1 + C2 double mutant and further found significant up-regulation of FfSdhC2 in ∆FfSdhC1, indicating that FfSdhC1 and -C2 might be essential for fungal growth although the FfSdhC2 deletion mutant was indistinguishable from the wild-type strain. These findings provide useful information for enhancing our understanding of the biological functions of the Sdh subunits in pathogenic fungi. [ABSTRACT FROM AUTHOR]

Nitrogen (N), as one of the most abundant mineral elements in rice, not only is the primary limiting factor for rice yield, but also impacts plant disease resistance by modulating plant morphology, regulating biochemical characteristics, as well as enhancing metabolic processes. Bacterial blight, a severe bacterial disease caused by Xanthomonas oryzae pv. oryzae (Xoo), significantly impairing rice yield and quality. Previous studies have shown that moderate application of nitrate nitrogen can improve plant disease resistance. However, further exploration is urgently required to investigate the involvement of the nitrate nitrogen signaling pathway in conferring resistance against bacterial leaf blight. In this study, we employed transcriptome sequencing to analyze the differentially expressed genes under various concentrations of nitrate supply duringrice bacterial blight infection. Our research reveals that nitrate nitrogen supply influences rice resistance to bacterial leaf blight. Through transcriptomic profiling of rice leaves inoculated under different nitrate nitrogen concentrations, we identified 4815 differentially expressed genes (DEGs) among four comparison groups, with notable differences in DEG enrichment between low and high nitrate nitrogen conditions, with some members of the NPF family implicated and we preliminarily elucidated the molecular regulatory network in which nitrate nitrogen participates in bacterial leaf blight resistance. Our findings provide a novel insight into a mechanism involving the nitrate nitrogen drive wider defense in rice. [ABSTRACT FROM AUTHOR]

Rice false smut caused by Ustilaginoidea virens has become one of the most important diseases of rice. Mycoviruses are viruses that can infect fungi with the potential to control fungal diseases. However, little is known about the biocontrol role of hypoviruses in U. virens. In this study, we revealed that the hypovirulence-associated U. virens strain Uv325 was co-infected by four novel mycoviruses from three lineages, designated Ustilaginoidea virens RNA virus 16 (UvRV16), Ustilaginoidea virens botourmiavirus virus 8 (UvBV8), Ustilaginoidea virens botourmiavirus virus 9 (UvBV9), and Ustilaginoidea virens narnavirus virus 13 (UvNV13), respectively. The U. virens strain co-infected by four mycoviruses showed slower growth rates, reduced conidial yield, and attenuated pigmentation. We demonstrated that UvRV16 was not only the major factor responsible for the hypovirulent phenotype in U. vriens, but also able to prevent U. virens to accumulate more mycotoxin, thereby weakening the inhibitory effects on rice seed germination and seedling growth. Additionally, we indicated that UvRV16 can disrupt the antiviral response of U. virens by suppressing the transcriptional expression of multiple genes involved in autophagy and RNA silencing. In conclusion, our study provided new insights into the biological control of rice false smut. [ABSTRACT FROM AUTHOR]

Plant‐mediated interactions between herbivores play an important role in regulating the composition of herbivore community. The fall armyworm (FAW), Spodoptera frugiperda, which has become one of the most serious pests on corn in China since it invaded in 2018, has been found feeding rice in the field. However, how FAW interacts with native rice insect pests remains largely unknown. Here, we investigated the interaction between FAW and a resident herbivore, striped stem borer (SSB, Chilo suppressalis) on rice. The infestation of rice leaf sheaths (LSs) by SSB larvae systemically enhanced the level of jasmonic acid (JA), abscisic acid (ABA), and trypsin proteinase inhibitors (TPIs), reduced relative water content (RWC) in leaf blades (LBs), and suppressed the growth of FAW larvae. In contrast, because FAW larvae infested LBs and did not affect defence responses in LSs, they did not influence the performance of SSB larvae. Using different mutants, together with bioassays and chemical analysis, we revealed that SSB‐induced suppression of FAW larvae growth depended on both the SSB‐activated JA pathway and RWC in LBs, whereas the ABA pathway activated by SSB larvae promoted the growth of FAW larvae by impeding water loss. These results provide new insights into mechanisms underlying plant‐mediated interactions between herbivores. [ABSTRACT FROM AUTHOR]

LuxR-type regulators play pivotal roles in regulating numerous bacterial processes, including bacterial motility and virulence, thereby exerting a significant influence on bacterial behavior and pathogenicity. Xanthomonas oryzae pv. oryzicola, a rice pathogen, causes bacterial leaf streak. Our research has identified VmsR, which is a response regulator of the two-component system (TCS) that belongs to the LuxR family. These findings of the experiment reveal that VmsR plays a crucial role in regulating pathogenicity, motility, biofilm formation, and the production of extracellular polysaccharides (EPSs) in Xoc GX01. Notably, our study shows that the vmsR mutant exhibits a reduced swimming motility but an enhanced swarming motility. Furthermore, this mutant displays decreased virulence while significantly increasing EPS production and biofilm formation. We have uncovered that VmsR directly interacts with the promoter regions of fliC and fliS, promoting their expression. In contrast, VmsR specifically binds to the promoter of gumB, resulting in its downregulation. These findings indicate that the knockout of vmsR has profound effects on virulence, motility, biofilm formation, and EPS production in Xoc GX01, providing insights into the intricate regulatory network of Xoc. [ABSTRACT FROM AUTHOR]

ABSTRACT NAC transcription factors (TFs) are pivotal in plant immunity against diverse pathogens. Here, we report the functional and regulatory network of MNAC3, a novel NAC TF, in rice immunity. MNAC3, a transcriptional activator, negatively modulates rice immunity against blast and bacterial leaf blight diseases and pathogen‐associated molecular pattern (PAMP)‐triggered immune responses. MNAC3 binds to a CACG cis‐element and activates the transcription of immune‐negative target genes OsINO80, OsJAZ10, and OsJAZ11. The negative function of MNAC3 in rice immunity depends on its transcription of downstream genes such as OsINO80 and OsJAZ10. MNAC3 interacts with immunity‐related OsPP2C41 (a protein phosphatase), ONAC066 (a NAC TF), and OsDjA6 (a DnaJ chaperone). ONAC066 and OsPP2C41 attenuate MNAC3 transcriptional activity, while OsDjA6 promotes it. Phosphorylation of MNAC3 at S163 is critical for its negative functions in rice immunity. OsPP2C41, which plays positive roles in rice blast resistance and chitin‐triggered immune responses, dephosphorylates MNAC3, suppressing its transcriptional activity on the target genes OsINO80, OsJAZ10, and OsJAZ11 and promoting the translocation of MNAC3 from nucleus to cytoplasm. These results establish a MNAC3‐centered regulatory network in which OsPP2C41 dephosphorylates MNAC3, attenuating its transcriptional activity on downstream immune‐negative target genes in rice. Together, these findings deepen our understanding of molecular mechanisms in rice immunity and offer a novel strategy for genetic improvement of rice disease resistance. [ABSTRACT FROM AUTHOR]

Summary: Plants typically activate distinct defense pathways against various pathogens. Heightened resistance to one pathogen often coincides with increased susceptibility to another pathogen. However, the underlying molecular basis of this antagonistic response remains unclear.Here, we demonstrate that mutants defective in the transcription factor ETHYLENE‐INSENSITIVE 3‐LIKE 2 (OsEIL2) exhibited enhanced resistance to the biotrophic bacterial pathogen Xanthomonas oryzae pv oryzae and to the hemibiotrophic fungal pathogen Magnaporthe oryzae, but enhanced susceptibility to the necrotrophic fungal pathogen Rhizoctonia solani.Furthermore, necrotroph‐induced OsEIL2 binds to the promoter of OsWRKY67 with high affinity, leading to the upregulation of salicylic acid (SA)/jasmonic acid (JA) pathway genes and increased SA/JA levels, ultimately resulting in enhanced resistance.However, biotroph‐ and hemibiotroph‐induced OsEIL2 targets OsERF083, resulting in the inhibition of SA/JA pathway genes and decreased SA/JA levels, ultimately leading to reduced resistance. Our findings unveil a previously uncharacterized defense mechanism wherein two distinct transcriptional regulatory modules differentially mediate immunity against pathogens with different lifestyles through the transcriptional reprogramming of phytohormone pathway genes. [ABSTRACT FROM AUTHOR]

The Rice Sheath Mite, Steneotarsonemus spinki Smiley (Acari: Tarsonemidae) is a pest of Kharif Rice (wet rice) of West Bengal, causing losses every year. It initially infests leaf sheaths, moving later onto the grains. It is not known how the mite survives in the off season, which is important for devising management strategies. The present investigation was conducted to find out the sources of infestation of S. spinki. It was concentrated on four types of substrates: rice associated weeds, soil, rice grains of different ages (before and after harvesting) and rice stubbles. Mites detected in any of those possible sources were slide mounted in modified Berlese medium and examined under phase and differential interference contrast microscope for identification. Tarsonemid mites were found on some grassy weeds, but not Steneotarsonemus spinki Smiley. No tarsonemid mite was found in soil samples from infested fields. Steneotarsonemus spinki was found on rice grains of different ages and in stubbles. Hence, both rice grains and rice stubbles could be important sources of infestation of S. spinki to new plants at each season. [ABSTRACT FROM AUTHOR]

Bakanae disease is mainly caused by Fusarium fujikuroi and is a significant fungal disease with a number of disastrous consequences. It causes great losses in rice production. However, few studies have focused on the details of bakanae disease resistance in rice. Here, we summarize and discuss the progress of bakanae disease resistance in rice. Besides rice germplasm screening and resistance-related gene/quantitative trait locus (QTL) exploration, the route of pathogen invasion in rice plants was determined. We further discussed the regulation of phytohormone-related genes and changes in endogenous phytohormones in rice plants that are induced by the pathogen. To achieve better control of bakanae disease, the use of natural fungicides was assessed in this review. During rice—F. fujikuroi interactions, the infection processes and spatial distribution of F. fujikuroi in infected seedlings and adult plants exhibit different trends. Fungal growth normally occurs both in resistant and susceptible cultivars, with less abundance in the former. Generally, bakanae disease is seed-borne, and seed disinfection using effective fungicides should always be the first and main option to better control the disease. Besides the friendly and effective measure of using natural fungicides, breeding and utilization of resistant rice cultivars is also an effective control method. To some extent, rice cultivars with low grain quality, indica subspecies, and some dwarf or semi-dwarf rice germplasms are more resistant to bakanae disease. Although no highly resistant germplasms were obtained, 37 QTLs were located, with almost half of the QTLs being located on chromosome 1. Using omics methods, WRKYs and MAPKs were usually found to be regulated during rice—F. fujikuroi interactions. The regulation of certain phytohormone-related genes and changes in some endogenous phytohormones induced by the pathogen were clear, i.e., it downregulated gibberellin-related genes and repressed endogenous gibberellins in resistant genotypes, but the opposite results were noted in susceptible rice genotypes. Overall, exploring resistant germplasms or resistance-related genes/QTLs for the breeding of rice with bakanae disease resistance, expanding research on the complex mechanism of rice—F. fujikuroi interactions, and using cost-effective and eco-friendly innovative control methods against the disease are necessary for present and future bakanae disease management. [ABSTRACT FROM AUTHOR]

Enhancing carbohydrate export from source to sink tissues is considered to be a realistic approach for improving photosynthetic efficiency and crop yield. The rice sucrose transporters OsSUT1, OsSWEET11a and OsSWEET14 contribute to sucrose phloem loading and seed filling. Crucially, Xanthomonas oryzae pv. oryzae (Xoo) infection in rice enhances the expression of OsSWEET11a and OsSWEET14 genes, and causes leaf blight. Here we show that co‐overexpression of OsSUT1, OsSWEET11a and OsSWEET14 in rice reduced sucrose synthesis and transport leading to lower growth and yield but reduced susceptibility to Xoo relative to controls. The immunity‐related hypersensitive response (HR) was enhanced in the transformed lines as indicated by the increased expression of defence genes, higher salicylic acid content and presence of HR lesions on the leaves. The results suggest that the increased expression of OsSWEET11a and OsSWEET14 in rice is perceived as a pathogen (Xoo) attack that triggers HR and results in constitutive activation of plant defences that are related to the signalling pathways of pathogen starvation. These findings provide a mechanistic basis for the trade‐off between plant growth and immunity because decreased susceptibility against Xoo compromised plant growth and yield. Summary statement: The study reported in this manuscript concerns the emerging topic of the roles played by SWEET sugar transporters in plant immunity. The data reported in this manuscript show that overexpression of Clade III SWEET sucrose transporters OsSWEET11a and OsSWEET14 that are exploited by bacterial blight pathogen Xanthomonas oryzae pv. oryzae to acquire sugars for its propagation elicits immune responses and activates plant defence responses leading to enhanced resistance against bacterial as well as fungal pathogens. The findings obtained by the overexpression of OsSWEET11a and OsSWEET14 in rice show that sucrose transport occurs via an apoplastic route, and overexpression of these sugar transporters inhibits sucrose synthesis and transport, which explains the inverse relationships between plant growth and yield, and resistance to pathogens. Moreover, our results show that sucrose transport and pathogen responses are coupled processes, and provide evidence for the concept that pathogen‐induced starvation is linked to plant defence. Also, to the best of our knowledge this is the first study where we show that disease susceptibility genes OsSWEET11a and OsSWEET14 can lead to hypersensitive reaction leading to enhanced plant immunity. [ABSTRACT FROM AUTHOR]

Application of radio frequency (RF) treatment has been studied for disinfesting agricultural products, and RF heating non-uniformity has been demonstrated to directly influence pest mortality in treated products. The purpose of this study was to investigate the combined effects of holding time after conveyor movement, layer rearrangement, and sample mixing on the mortality of Rhyzopertha dominica (R. dominica) in milled rice treated with hot air-assisted RF heating. Results showed that hot-air assistance during the process of RF heating can lead to a rapid temperature rise and improve the temperature distribution. RF heating followed by holding samples in hot air for specific time periods effectively improved the heating uniformity of samples and raised the mortality of R. dominica in milled rice. Compared with the stationary conditions, conveyor movement, layer rearrangement, and sample mixing improved the hot air-assisted RF heating uniformity of the sample, raised pest mortality and reduced the thermal holding time after RF treatment required to achieve 100% pest mortality in milled rice. The findings of this study provide a valuable proof of concept for improving RF heating uniformity and optimizing parameters in RF disinfestation protocols for milled rice. [ABSTRACT FROM AUTHOR]

Traditional small‐holder agricultural landscapes in southern China are being consolidated to increase mechanisation levels in agriculture, but it is unclear how this influences rice arthropod communities in these landscapes.Here, based on a six‐year study in 20 rice fields, we evaluated the impact of land consolidation on arthropod communities, crop damage, and rice yield. We also analysed how effects of land consolidation were moderated by the proportion of large semi‐natural habitat patches and insecticide use.We found that, compared to consolidated fields, rice fields in traditional farmlands had a higher abundance and family richness of natural enemies, but a similar abundance of rice pests. Land consolidation did not significantly interact with the proportion of large semi‐natural habitat patches or insecticide application, in terms of affecting arthropods. The proportion of semi‐natural habitat reduced the negative effect of insecticide application on key rice pests, but no equivalent interaction occurred for natural enemies.Synthesis and applications: Land consolidation can have negative impacts on the abundance and richness of natural enemies, but not pests in small‐holder rice systems, and these impacts are independent from insecticide application and proportion of semi‐natural habitat in the landscape. We recommend the implementation of agri‐environmental measures or re‐establishing field margin vegetation during the consolidation process to mitigate these potential negative effects, although trade‐off between enhancing crop yields and preserving rice arthropod biodiversity should be considered. We encourage future research to focus on the detailed assessment of the function of linear habitats for a better understanding of the impact of land consolidation. [ABSTRACT FROM AUTHOR]

[Objectives] Aiming at the lack of disease description in rice diseases and pests image classification technology, a lightweight rice diseases and pests image description model was proposed in this paper to describe rice diseases and pests image more specifically. [Methods] Ten common rice pests and diseases, such as rice bacterial blight, rice bacterial streak disease, rice bakanae disease, rice three chemical borers, rice blast, rice false smut, rice sheath blight, rice planthopper, rice thrip and rice brown spot were studied, and Chinese description data set of rice pests and diseases image was constructed. Firstly, the multimodal pre-training model CLIP was used to generate image vectors, which contained basic image information and rich semantic information. The mapping network was used to map the image vectors into the text space to generate text prompt vectors. Finally, the language model GPT-2 generates image descriptions according to the prompt vectors. [Results] The test results showed that the indexes of the model in this paper were significantly superior to other models in the image description data set of rice pests and diseases. Compared with the traditional CNN_ LSTM model, the indexes of BLEU-1, BLEU-2, BLEU-3, BLEU-4, ROUGE and METEOR improved 0.26, 0.27, 0.24, 0.22, 0.22 and 0.14, respectively. And the generated image description had the advantages of accurate, detailed and rich semantics. The model was tested by using actual rice field pictures. The actual field scenes were more complex and diverse, and the generated image description index only slightly decreased compared with the data set index, which was still higher than other comparison models. The overall recognition accuracy of the model was 97.28%. [Conclusions] The image description method of rice diseases and pests based on multimodal pre-training model can accurately describe the rice diseases and pests, and provide a new idea for the detection of rice diseases and pests. [ABSTRACT FROM AUTHOR]

Sheath blight (ShB) is the most serious disease of rice (Oryza sativa L.), caused by the soil-borne fungus Rhizoctonia solani Kühn (R. solani). It poses a significant threat to global rice productivity, resulting in approximately 50% annual yield loss. Managing ShB is particularly challenging due to the broad host range of the pathogen, its necrotrophic nature, the emergence of new races, and the limited availability of highly resistant germplasm. In this study, we conducted QTL mapping using an F2 population derived from a cross between a partially resistant accession (IRGC81941A) of Oryza nivara and the susceptible rice cultivar Punjab rice 121 (PR121). Our analysis identified 29 QTLs for ShB resistance, collectively explaining a phenotypic variance ranging from 4.70 to 48.05%. Notably, a cluster of four QTLs (qRLH1.1, qRLH1.2, qRLH1.5, and qRLH1.8) on chromosome 1 consistently exhibit a resistant response against R. solani. These QTLs span from 0.096 to 420.1 Kb on the rice reference genome and contain several important genes, including Ser/Thr protein kinase, auxin-responsive protein, protease inhibitor/seed storage/LTP family protein, MLO domain-containing protein, disease-responsive protein, thaumatin-like protein, Avr9/Cf9-eliciting protein, and various transcription factors. Additionally, simple sequence repeats (SSR) markers RM212 and RM246 linked to these QTLs effectively distinguish resistant and susceptible rice cultivars, showing great promise for marker-assisted selection programs. Furthermore, our study identified pre-breeding lines in the advanced backcrossed population that exhibited superior agronomic traits and sheath blight resistance compared to the recurrent parent. These promising lines hold significant potential for enhancing the sheath blight resistance in elite cultivars through targeted improvement efforts. [ABSTRACT FROM AUTHOR]

Half of the world's population depends on rice for their calories. Protecting rice in the growth period from damage caused by phytopathogens is faced with a great challenge under the frequent extreme climate. To find novel fungicides to control rice diseases, 35 novel phenylthiazole‐1,3,4‐oxadiazole‐thioether (sulfone) derivatives were synthesized and evaluated for their efficacy against destructive fungal and bacterial diseases of rice. Bioassay results demonstrated that most of G‐series compounds possessed excellent antifungal and antibacterial activities. In particular, compounds G1 (EC50 = 2.22 μg/mL, R.s) and G7 (EC50 = 2.76 μg/mL, R.s) showed the most promising antifungal activities in vitro and exhibited superior protective and curative activities against rice sheath blight in vivo compared with commercial carbendazim. Surprisingly, compound G2 exhibited the remarkable antibacterial activity against Xanthomonas oryzae pv. oryzae (Xoo) with an EC50 value of 1.98 μg/mL, and demonstrated superior protective activity (88.08%) than thiodiazole copper (79.39%) against rice bacterial leaf blight at 200 μg/mL. The abovementioned results fully manifested that the phenylthiazole‐1,3,4‐oxadiazole‐sulfone structure, especially compounds G1 and G2, had the potential to develop as commercial agents for controlling rice fungal and bacterial diseases. [ABSTRACT FROM AUTHOR]

Bacterial panicle blight (BPB) is an emerging rice disease in Nigeria, causing up to 75% yield loss and widespread globally. In the 2019 season, rice farmers in Zamfara State's Gusau, Talata Mafara, Maradun, and Bakura communities reported significant yield declines due to an unidentified disease. Infected samples suggested BPB as the cause, yet the pathogen had not been identified in Nigeria. A trial was conducted to identify and characterize BPB pathogens in Zamfara State, aiming to screen rice germplasm and find resistant sources. Infected rice grains from the region were collected and cultured on King's B medium at 37°C for 48 hours in the microbiology lab of Federal University Gusau. The bacteria were purified to single colonies and analyzed morphologically and via polymerase chain reaction (PCR), identifying the strain as Burkholderia glumae. This strain produced toxoflavin, a compound linked to its pathogenicity. PCR amplification of a 1079- bp fragment using gyrB-specific primers confirmed B. glumae as the BPB agent in Nigeria. A pathogenicity test was performed on three commercial rice varieties (Faro 44, FARO 56, and FARO 59) using the syringe inoculation method at the Biological Garden, Department of Biological Sciences, Federal University Gusau. All inoculated rice varieties exhibited typical BPB symptoms within three days, similar to those seen in naturally infected rice panicles. This confirmed B. glumae as the causative pathogen and highlighted the urgent need for resistant rice varieties. [ABSTRACT FROM AUTHOR]

Rice consumption, particularly of highly processed white rice (WR), has been associated with increased risk of insulin resistance (IR). This study aimed to compare the impact of consuming WR versus brown rice (BR) from five common local rice varieties in Nigeria on the development of IR using a Wistar albino rat model. Five local rice cultivars (Jamila, Kwandala, MBC, Yarkatabore, Farar jalof) were collected, with one set kept unpolished (BR) and the other polished (WR). Proximate analysis and quantification of bioactive compounds (total phenols, flavonoids) were performed. Wistar albino rats were fed either a normal diet, high-fat diet, or diets containing 100% BR or WR for 12 weeks. Body weight, fasting blood glucose, glycogen, triglycerides were assessed. BR varieties had higher protein, fiber, and carbohydrate content compared to WR. BR also exhibited significantly greater total phenolic and flavonoid contents. Rats fed BR showed no significant weight gain (p<0.05), while some WR groups gained weight. Fasting blood glucose was elevated in WR groups versus control and BR groups. Blood glycogen was lower, and triglycerides higher, in certain WR groups. Consumption of BR varieties may confer protective effects against IR compared to WR in this rat model. These findings highlight the potential metabolic health benefits of incorporating local BR varieties into the diet to mitigate development of chronic disorders. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Southern rice black‐streaked dwarf virus (SRBSDV) transmitted by Sogatella furcifera constitutes a threat to sustainable rice production. However, most rice varieties are highly vulnerable to SRBSDV, whereas the occurrence of the viral disease varies significantly under field conditions. This study aimed to evaluate the potential of rice varietal resistance to S. furcifera in reducing SRBSDV transmission. RESULTS: Among the five rice varieties, Zhongzheyou8 and Deyou108 exhibited high resistance to S. furcifera, Baixiangnuo33 was susceptible, and TN1 and Diantun502 were highly susceptible. The S. furcifera generally showed non‐preference for and low feeding on the Zhongzheyou8 and Deyou108 plants, which may explain the resistance of these varieties to S. furcifera. Transmission of SRBSDV by S. furcifera was significantly impaired on the resistant varieties, both inoculation and acquisition rates were much lower on Zhongzheyou8 than on TN1. The short durations of S. furcifera salivation and phloem‐related activities and the low S. furcifera feeding amount may explain the reduced SRBSDV inoculation and acquisition rates associated with Zhongzheyou8. Spearman's rank correlation revealed a significant negative correlation between S. furcifera resistance and SRBSDV transmission among the tested varieties. CONCLUSION: The results indicate that rice varietal resistance to the vector S. furcifera hinders SRBSDV transmission, which is largely associated with the host plant selection and feeding behaviors of the vector. The current findings shed light on the management of the SRBSDV viral disease through incorporation of S. furcifera resistant rice varieties in the management protocol. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Rice is considered one the most important plants globally because it is a source of food for over half the world’s population. Like other plants, rice is susceptible to diseases that may affect the quantity and quality of produce. Because of this, crops sometimes lose 20% to 40% of their value. A good harvest can depend on early discovery of these diseases, so farmers would need to be able to read and understand images of the diseases. Also, farmers still can't reach their goal of doing daily studies of their huge farmlands. It would be very expensive to do this, so the price of rice for buyers would go up even if it were possible. This paper proposed a pre-trained Deep Convolutional Neural Network (DCNN) method based on optimization for accurately finding and classifying rice leaf disease. It uses both transfer learning and baseline learning. A precise diagnosis method can find and classify eleven different types of rice diseased healthy, leaf blast, brown spot, bacterial blight and bacterial leaf blight, false stump, neck blast, stemborer, tumgro, hispa, and BPH. The most advanced large-scale architecture, such as XceptionNet, ResNet50, DenseNet VGG19, SequeezeNet and CNN used for recognition of the Rice disease, with SGDM, ADAM, RMS propagation optimization methods for predictions for a dataset. The -proposed models were trained and tested using datasets gathered from websites. In the simulation results consistently demonstrate that the XceptionNet model outperforms other architectures in terms of higher accuracy 93.3 %. [ABSTRACT FROM AUTHOR]