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Due to the innumerable benefits and uses of moringa and rice in terms of health and food products, many researches were conducted mainly for the exploration of these components. However, despite their much-studied properties in various applications, skincare was one area that they have missed. Researchers lacked investigations about how moringa and rice can be used externally, much more to be used together in one product. Because of this, the researchers intended to discover the potential of MORIAH: Moringa and Rice Blotting Paper and to explore such areas to find factual evidence as to why these components are beneficial for human skin. Specifically, they aimed to answer several questions regarding the acceptability of the product in terms of smell, texture, and thickness, as well as its efficacy in terms of strength and oil absorption. Moreover, they also identified the significant differences between the experimented and the controlled products. The results showed that Moringa and rice are acceptable components in making a blotting paper, however the product was not suitable for other paper uses as it did not meet the strength classification requirements. Although, the product was effective in terms of oil absorption and the facial oil content of each respondent was found to be better absorbed using MORIAH: Moringa and Rice Blotting Paper compared to a commercially produced product. [ABSTRACT FROM AUTHOR]

Because virus vectors can spread systemically autonomously, they are powerful vehicles with which to deliver genome-editing tools into plant cells. Indeed, a vector based on a positive-strand RNA virus, potato virus X (PVX), harboring SpCas9 and its single guide RNA (sgRNA), achieved targeted mutagenesis in inoculated leaves of Nicotiana benthamiana. However, the large size of the SpCas9 gene makes it unstable in the PVX vector, hampering the introduction of mutations in systemic leaves. Smaller Cas variants are promising tools for virus vector-mediated genome editing; however, they exhibit far lower nuclease activity than SpCas9. Recently, AsCas12f, one of the smallest known Cas proteins so far (one-third the size of SpCas9), was engineered to improve genome-editing activity dramatically. Here, we first confirmed that engineered AsCas12f variants including I123Y/D195K/D208R/V232A exhibited enhanced genome-editing frequencies in rice. Then, a PVX vector harboring this AsCas12f variant was inoculated into N. benthamiana leaves by agroinfiltration. Remarkably, and unlike with PVX-SpCas9, highly efficient genome editing was achieved, not only in PVX-AsCas12f-inoculated leaves but also in leaves above the inoculated leaf (fourth to sixth upper leaves). Moreover, genome-edited shoots regenerated from systemic leaves were obtained at a rate of >60%, enabling foreign DNA-free genome editing. Taken together, our results demonstrate that AsCas12f is small enough to be maintained in the PVX vector during systemic infection in N. benthamiana and that engineered AsCas12f offers advantages over SpCas9 for plant genome editing using virus vectors. [ABSTRACT FROM AUTHOR]

The mechanized direct seeding of rice (Oryza sativa L.) is a major trend nowadays. The elongation of rice mesocotyl and coleoptile can facilitate the rapid emergence of seedlings under deep mechanized sowing. Currently, most of the cultivated rice accessions have short mesocotyls or coleoptiles, with only a few related genes cloned. However, understanding and enhancing the ability of rice seedlings to rapidly emerge from deep sowing depths is crucial. Herein, we assessed 745 core rice germplasm accessions sown under a soil cover depth of 10 cm and found few long mesocotyl and coleoptile germplasms. We conducted genome‐wide association study using six models to obtain three or more multi‐model co‐localization candidate regions and calculated Fst between the phenotypes of extreme samples to determine genetic differences. The candidate regions associated with mesocotyl and coleoptile lengths were identified by integrating Fst and multi‐model localization results. This multi‐model localization method may accelerate the mining of genes related to the mesocotyl and coleoptile, providing valuable targets for functional validation and marker‐assisted selection in rice breeding programs. [ABSTRACT FROM AUTHOR]

Summary Genome editing is a revolution in biotechnology for crop improvement with the final product lacking transgenes. However, most derived traits have been generated through edits that create gene knockouts. Our study pioneers a novel approach, utilizing gene editing to enhance gene expression by eliminating transcriptional repressor binding motifs. Building upon our prior research demonstrating the protein‐boosting effects of the transcription factor NF‐YC4, we identified conserved motifs targeted by RAV and WRKY repressors in the NF‐YC4 promoters from rice (Oryza sativa) and soybean (Glycine max). Leveraging CRISPR/Cas9 technology, we deleted these motifs, resulting in reduced repressor binding and increased NF‐YC4 expression. This strategy led to increased protein content and reduced carbohydrate levels in the edited rice and soybean plants, with rice exhibiting up to a 68% increase in leaf protein and a 17% increase in seed protein, and soybean showing up to a 25% increase in leaf protein and an 11% increase in seed protein. Our findings provide a blueprint for enhancing gene expression through precise genomic deletions in noncoding sequences, promising improved agricultural productivity and nutritional quality. [ABSTRACT FROM AUTHOR]

Jiangxi Province is a major province of rice breeding and planting in China. With the rapid improvement of rice breeding level, local varieties were constantly replaced by new varieties, resulted in the loss of a large number of excellent genes and the significant reduction of genetic diversity, and the genetic basis was increasingly narrow. The genetic diversity of 256 new rice varieties in Jiangxi Province was analyzed using the DUS test guide characteristics, aiming to understand the genetic diversity of new rice varieties in Jiangxi Province and provided some references for rice germplasm identification, breeding utilization and new variety testing in Jiangxi Province. The coefficient of variation of the 10 quantitative characteristics ranged from 8. 59% to 21. 83%, the Shannon-Wiener genetic diversity index of the 52 tested characteristics ranged from 0. 03 to 2. 10, with an average of 1. 05, and the cluster analysis showed that the material similarity coefficient ranged from 0. 77 to 0. 95. In recent years, the diversity of varieties selected and bred in Jiangxi Province was relatively narrow, and the development of special rice varieties was also insufficient, such as glutinous rice, colored rice and fragrant rice. [ABSTRACT FROM AUTHOR]

[Objective] To utilize existing resources to create new excellent restoring and sterile lines, and to breed new hybrid rice varieties with high yield, quality and disease resistance. [Method] The high-yielding, large panicle and strong stem (HR1128/Chenghui 727) F3 selected line was used as the female parent and the early maturing and blast resistant Wushan silk seedling was used as the male parent. A new restoring line Zhunongzhan 110 with strong restoring ability, good combining ability and resistance to rice blast was selected through multiple generations of selection and cross testing with multiple three line sterile lines. In the multi-point comparison experiment, the combination with Zhu 99A showed the characteristics of high yield, high quality, disease resistance and lodging resistance, so it was named Zhuyou 110. In 2020-2021, Zhuyou 110 participated in regional trials of late maturing medium Indica rice in the middle and lower reaches of the Yangtze River and photosensitive late Indica rice in southern China. [Result] In the regional trial of late maturing medium Indica rice in the middle and lower reaches of the Yangtze River, the average yield of Zhuyou 110 in the two-year regional trial was 9.70 t/ hm², enhanced by 6.6% compared with CK. In the 2021 production test, the average yield was 10.13 t/ hm², enhanced by 5.9% compared with CK. It showed high yield, lodging resistance and moderate resistance to rice blast, which reached the second level of the Quality of Edible Rice Varieties (NY/ T 593— 2013) standard in the agricultural industry, approved by the National Crop Variety Approval Committee (Authorization code:Guoshendao 20220021). [Conclusion] Zhuyou 110 had the advantages of high yield, high quality, lodging resistance and moderate resistance to rice blast, which was suitable for planting one mid-season rice in the middle and lower reaches of the Yangtze River and double late-season rice in the southern rice region. [ABSTRACT FROM AUTHOR]

Abiotic stress is one of the major factors restricting the production of rice (Oryza sativa L.). Developing rice varieties with dual abiotic stress tolerance is essential to ensure sustained rice production, which is necessary to illustrate the regulation mechanisms underlying dual stress tolerance. At present, only a few genes that regulate dual abiotic stress tolerance have been reported. In this study, we determined that the expression of OsMT2b was induced by both drought and Cd2+ stress. After stress treatment, OsMT2b-overexpression lines exhibited enhanced drought tolerance and better physiological performance in terms of relative water content and electrolyte leakage compared with wild-type (WT). Further analysis indicated that ROS levels were lower in OsMT2b-overexpression lines than in WT following stress treatment, suggesting that OsMT2b-overexpression lines had a stronger ability to scavenge ROS under stress. Reverse transcription-quantitative PCR (RT-qPCR) results demonstrated that under drought stress, OsMT2b influenced the expression of genes involved in ROS scavenging to enhance drought tolerance in rice. In addition, OsMT2b-overexpression plants displayed increased tolerance to Cd2+ stress, and physiological assessment results were consistent with the observed phenotypic improvements. Thus, enhancing ROS scavenging ability through OsMT2b overexpression is a novel strategy to boost rice tolerance to both drought and Cd2+ stress, offering a promising approach for developing rice germplasm with enhanced resistance to the abiotic stressors. [ABSTRACT FROM AUTHOR]

Summary Plant root system is significantly influenced by high soil levels of ammonium nitrogen, leading to reduced root elongation and enhanced lateral root branching. In Arabidopsis, these processes have been reported to be mediated by phytohormones and their downstream signaling pathways, while the controlling mechanisms remain elusive in crops. Through a transcriptome analysis of roots subjected to high/low ammonium treatments, we identified a cytokinin oxidase/dehydrogenase encoding gene, CKX3, whose expression is induced by high ammonium. Knocking out CKX3 and its homologue CKX8 results in shorter seminal roots, fewer lateral roots, and reduced sensitivity to high ammonium. Endogenous cytokinin levels are elevated by high ammonium or in ckx3 mutants. Cytokinin application results in shorter seminal roots and fewer lateral roots in wild‐type, mimicking the root responses of ckx3 mutants to high ammonium. Furthermore, CKX3 is transcriptionally activated by type‐B RR25 and RR26, and ckx3 mutants have reduced auxin content and signaling in roots under low ammonium. This study identified RR25/26‐CKX3‐cytokinin as a signal module that mediates root responses to external ammonium by modulating of auxin signaling in the root meristem and lateral root primordium. This highlights the critical role of cytokinin metabolism in regulating rice root development in response to ammonium. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) pollution is a serious threat to food safety and human health. Minimization of Cd uptake and enhancing Cd tolerance in plants are vital to improve crop yield and reduce hazardous effects to humans. In this study, we investigate the effect of a synergistic system with phytohormone (24-Epibrassinolide, EBL) and silicon (Si) on Cd toxicity and accumulation of rice plants. The results revealed that Si, EBL and their combination rescued Cd-induced growth inhibition, as evidenced by the increased dry weight of root and shoot. The chlorophyll content and photosynthetic performance were improved. The activity of antioxidant enzymes (SOD, POD and CAT) was increased and oxidative stress was alleviated. More importantly, Cd content in root was decreased by 20.25%, 17.72% and 27.84%, while Cd content in shoot decreased by 21.17%, 16.47% and 25.88%, respectively. Moreover, Si, EBL and Si + EBL treatment enriched cell wall-bound Cd and reduced Cd toxicity to functional organelles. Meanwhile, the residual form of Cd was enriched and the highly toxic forms of Cd (inorganic and water-soluble Cd) were decreased. The joint application showed better effects than applying Si and EBL alone. Collectively, this study provides an effective way for Cd toxicity mitigation in rice plants. [ABSTRACT FROM AUTHOR]

The rice paddy-direct seeding system has been widely adopted due to its low cost and convenience, whereas its application is mainly constrained by low seedling vigor, cold sensitivity, eventually resulting in reduced grain yield. Here, we show vig1a and vig1b, two allelic mutants of OsbZIP01, that both demonstrate greatly enhanced seedling vigor and chilling tolerance but differ in final grain production. The vig1a phenotype can be obtained via simultaneous mutation of the genes OsbZIP01 and OsbZIP18, or by selectively manipulating the basic region of OsbZIP01. Destroying the leucine zipper region of OsbZIP01 in vig1a turns vig1a to be vig1b. Further analysis reveals that OsbZIP01 and OsbZIP18 function cooperatively in diverse crucial biological programs that determine seedling establishment, chilling tolerance, and grain yield through their interactions. These findings provide a strategy toward simultaneously improving seedling vigor, chilling tolerance, and grain yield for rice production. Very few genes are involved in simultaneous regulation of seedling vigor, cold tolerance and grain yield in rice. Here, the authors report OsbZIP01 and OsbZIP18 function cooperatively in determining seedling establishment, chilling tolerance, and grain yield in rice. [ABSTRACT FROM AUTHOR]

Introduction: More than half of the world's population consumes rice as their primary food. The majority of rice production is concentrated in Asia, with the top 10 rice-growing countries accounting for 84% of the world's total rice cultivation. However, rice production is also strongly linked to environmental changes. Among all the global sources of greenhouse gas (GHG) emissions, paddy cultivation stands out as a significant contributor to global methane (CH4) and nitrous oxide (N2O) emissions. This contribution is expected to increase further with the projected increase of 28% in global rice output by 2050. Hence, modifications to rice management practices are necessary both to increase yield and mitigate GHG emissions. Methods: We investigated the effect of seedling treatment, soil application, and foliar application of a methane-derived microbial biostimulant on grain yield and GHG emissions from rice fields over three seasons under 100% fertilizer conditions. Further, microbial biostimulant was also tested under 75% nitrogen (N) levels to demonstrate its effect on grain yield. To understand the mechanism of action of microbial biostimulant on crop physiology and yield, a series of physiological, transcript, and metabolite analyses were also performed. Results: Our three-season open-field studies demonstrated a significant enhancement of grain yield, up to 39%, with a simultaneous reduction in CH4 (31%-60%) and N2O (34%-50%) emissions with the use of methane-derived microbial biostimulant. Under 75% N levels, a 34% increase in grain yield was observed with microbial biostimulant application. Based on the physiological, transcript, and metabolite analyses data, we were further able to outline the potential mechanisms for the diverse synergistic effects of methane-derived microbial biostimulant on paddy, including indole-3-acetic acid production, modulation of photosynthesis, tillering, and panicle development, ultimately translating to superior yield. Conclusion: The reduction in GHG emission and enhanced yield observed under both recommended and reduced N conditions demonstrated that the methane-derived biostimulant can play a unique and necessary role in the paddy ecosystem. The consistent improvements seen across different field trials established that the methane-derived microbial biostimulant could be a scalable solution to intensify rice productivity with a lower GHG footprint, thus creating a win--win--win solution for farmers, customers, and the environment. [ABSTRACT FROM AUTHOR]

Short-chain dehydrogenase/reductases (SDRs) are the largest NAD(H)-dependent oxidoreductase superfamilies and are involved in diverse metabolisms. This study presents a comprehensive genomic analysis of the SDR superfamily in Cinnamomum camphora, a species that is one of the most significant woody essential oil plants in southern China. We identify a total of 222 CcSDR proteins and classify them into five types based on their cofactor-binding and active sites: 'atypical', 'classic', 'divergent', 'extended', and 'unknown'. Phylogenetic analysis reveals three evolutionary branches within the CcSDR proteins, and further categorization using the SDR-initiative Hidden Markov model resulted in 46 families, with the CcSDR110C, CcSDR108E, and CcSDR460A families being the most populous. Collinearity analysis identified 34 pairs of CcSDR paralogs in C. camphora, 141 pairs of SDR orthologs between C. camphora and Populus trichocarpa, and 59 pairs between C. camphora and Oryza sativa. Expression profile analysis indicates a preference for the expression of 77 CcSDR genes in specific organs such as flowers, bark, twigs, roots, leaves, or fruits. Moreover, 77 genes exhibit differential expression patterns during the four developmental stages of leaves, while 130 genes show variance across the five developmental stages of fruits. Additionally, to explore the biosynthetic mechanism of methyl eugenol, a key component of the leaf essential oil in the methyl eugenol chemotype, this study also identifies eugenol synthase (EGS) within the CcSDR460A family through an integrated strategy. Real-time quantitative PCR analysis demonstrates that the expression of CcEGS in the leaves of the methyl eugenol chemotype is more than fourfold higher compared to other chemotypes. When heterologously expressed in Escherichia coli, it catalyzes the conversion of coniferyl acetate into a mixture predominantly composed of eugenol (71.44%) and isoeugenol (21.35%). These insights pave the way for future research into the functional diversity of CcSDR genes, with a focus on secondary metabolism. [ABSTRACT FROM AUTHOR]

Lignin is nature's second most abundant vascular plant biopolymer, playing significant roles in mechanical support, water transport, and stress responses. This study identified 90 lignin biosynthesis genes in rice based on phylogeny and motif constitution, and they belong to PAL, C4H, 4CL, HCT, C3H, CCoAOMT, CCR, F5H, COMT, and CAD families. Duplication events contributed largely to the expansion of these gene families, such as PAL, CCoAOMT, CCR, and CAD families, mainly attributed to tandem and segmental duplication. Microarray data of 33 tissue samples covering the entire life cycle of rice suggested fairly high PAL, HCT, C3H, CCoAOMT, CCR, COMT, and CAD gene expressions and rather variable C4H, 4CL, and F5H expressions. Some members of lignin-related genes (OsCCRL11, OsHCT1/2/5, OsCCoAOMT1/3/5, OsCOMT, OsC3H, OsCAD2, and OsPAL1/6) were expressed in all tissues examined. The expression patterns of lignin-related genes can be divided into two major groups with eight subgroups, each showing a distinct co-expression in tissues representing typically primary and secondary cell wall constitutions. Some lignin-related genes were strongly co-expressed in tissues typical of secondary cell walls. Combined HPLC analysis showed increased lignin monomer (H, G, and S) contents from young to old growth stages in five genotypes. Based on 90 genes' microarray data, 27 genes were selected for qRT-PCR gene expression analysis. Four genes (OsPAL9, OsCAD8C, OsCCR8, and OsCOMTL4) were significantly negatively correlated with lignin monomers. Furthermore, eleven genes were co-expressed in certain genotypes during secondary growth stages. Among them, six genes (OsC3H, OsCAD2, OsCCR2, OsCOMT, OsPAL2, and OsPAL8) were overlapped with microarray gene expressions, highlighting their importance in lignin biosynthesis. [ABSTRACT FROM AUTHOR]

The Casparian strip membrane domain proteins (CASPs) are pivotal for the formation of the Casparian strip (CS) in endodermal cells and play a crucial role in a plant's response to environmental stresses. However, existing research on the CASP gene family in rice and Arabidopsis lacks a comprehensive bioinformatics analysis and necessitates further exploration. In this study, we identified 41 OsCASP and 39 AtCASP genes, which were grouped into six distinct subgroups. Collinearity analysis underscored the pivotal roles of WGD and TD events in driving the evolution of CASPs, with WGDs being the dominant force. On the one hand, the analysis of cis-elements indicated that most OsCASP and AtCASP genes contain MYB binding motifs. On the other hand, RNA-seq revealed that the majority of OsCASP and AtCASP genes are highly expressed in roots, particularly in endodermal cells, where OsCASP_like11/9 and AtCASP_like1/31 demonstrated the most pronounced expression. These results suggest that OsCASP_like11/9 and AtCASP_like1/31 might be candidate genes involved in the formation of the endodermis CS. RT-qPCR results demonstrated that OsCASP_like2/3/13/17/21/30 may be candidate genes for the ion defect process. Collectively, this study offers a theoretical foundation for unraveling the biological functions of CASP genes in rice and Arabidopsis. [ABSTRACT FROM AUTHOR]

Based on the genome information of rice (Nipponbare), this study screened and identified six raffinose synthase (RS) genes and analyzed their physical and chemical properties, phylogenetic relationship, conserved domains, promoter cis-acting elements, and the function and genetic diversity of the gene-CDS-haplotype (gcHap). The results showed that these genes play key roles in abiotic stress response, such as OsRS5, whose expression in leaves changed significantly under high salt, drought, ABA, and MeJA treatments. In addition, the OsRS genes showed significant genetic variations in different rice populations. The main gcHaps of most OsRS loci had significant effects on key agronomic traits, and the frequency of these alleles varied significantly among different rice populations and subspecies. These findings provide direction for studying the RS gene family in other crops. [ABSTRACT FROM AUTHOR]

Seed germination is a pivotal stage in the plant life cycle, orchestrated by a myriad of internal and external factors, notably plant hormones. The underlying molecular mechanisms governing rice seed germination remain largely unelucidated. Herein, we uncover OsMBF1a as a crucial regulatory factor that employs a dual strategy to promote seed germination: positively activating genes involved in gibberellin (GA) biosynthesis pathways, while negatively regulating key genes responsible for abscisic acid (ABA) synthesis. Furthermore, OsMBF1a modulates the endogenous levels of ABA and GA in rice seeds, reinforcing its central role in the germination process. The expression of ZmMBF1a and ZmMBF1b, the homologous genes in maize, in rice seeds similarly affects germination, indicating the conserved functionality of MBF1 family genes in regulating seed germination. This study provides novel insights into the molecular mechanisms underlying rice seed germination and underscores the significance of MBF1 family genes in plant growth and development. [ABSTRACT FROM AUTHOR]

As a master regulator of seed development, Leafy Cotyledon 1 (LEC1) promotes chlorophyll (Chl) biosynthesis in Arabidopsis, but the mechanism underlying this remains poorly understood. Here, we found that loss of function of OsNF-YB7, a LEC1 homolog of rice, leads to chlorophyllous embryo, indicating that OsNF-YB7 plays an opposite role in Chl biosynthesis in rice compared with that in Arabidopsis. OsNF-YB7 regulates the expression of a group of genes responsible for Chl biosynthesis and photosynthesis by directly binding to their promoters. In addition, OsNF-YB7 interacts with Golden 2-Like 1 (OsGLK1) to inhibit the transactivation activity of OsGLK1, a key regulator of Chl biosynthesis. Moreover, OsNF-YB7 can directly repress OsGLK1 expression by recognizing its promoter in vivo, indicating the involvement of OsNF-YB7 in multiple regulatory layers of Chl biosynthesis in rice embryo. We propose that OsNF-YB7 functions as a transcriptional repressor to regulate Chl biosynthesis in rice embryo. [ABSTRACT FROM AUTHOR]

Soil fertility is one of the most important influencing factors on the rice yield. Among them, the relationship between soil physical and chemical properties and rice yield can greatly contribute to rice production and fertilizer cultivation in different regions. This study aims to analyze the absolute rice yield, relative yield, and sustainable yield index on the county scale. The research area was also selected as Fangzheng County in northeast China, Ningxiang City in the middle reaches of the Yangtze River, and Jinxian County in the middle and lower reaches of the Yangtze River. The key factors of soil fertility were then determined to affect the rice yield in different regions. The results show that the two-season rice yield (9414.89 kg/hm²) in Ningxiang City was significantly higher than that in Fangzheng County (8224.31 kg/hm²) and Jinxian County (5691.38 kg/hm²) in the late season, due to different cropping patterns. But the average relative yield in Fangzheng County (89.88%) was significantly higher than that in Ningxiang City (73.84%) and Jinxian County (65.67%). The sustainable yield index of Fangzheng County was also higher (0.86), indicating high yield and stability. Furthermore, the low, medium, and high yield levels were calculated using relative yields. Therefore, the soil fertility index and integrated fertility index of Fangzheng County, Ningxiang City, and Jinxian County were higher under the high yield level. Among them, the soil organic matter index, available nitrogen index, and integrated fertility index of Fangzheng County at the high yield level increased by 25.50%, 31.17%, and 25.45%, respectively, compared with the low yield level. The soil available phosphorus increased by 35.41% in Ningxiang City, compared with the low yield level. The soil organic matter, available nitrogen, available phosphorus, available potassium, and integrated fertility index of Jinxian County showed that the high yield level was significantly higher than the middle and low yield levels, which increased 13.28%-27.28%, 21.45%-34.82%, 62.42%-111.90%, 29.51%-59.51%, and 34.21%-75.86%, respectively. There was no significant difference in the soil pH value among different yield levels. There was a variation in the fertility influencing factors on the relative yield in different counties. The soil's available phosphorus, nitrogen, and organic matter content were the key fertility factors for the sustainable yield index of rice in Fangzheng County, Ningxiang City, and Jinxian County, respectively. Some suggestions were provided for soil fertilizer cultivation in the high and stable rice yield at the county scale. In Fangzheng County, the soil available phosphorus shared the largest relative contribution to the rice sustainable yield index (8.68%), followed by organic matter and available potassium. In Ningxiang, the relative contribution of soil available nitrogen to rice sustainable yield index was 12.92%, followed by pH. In Jinxian County, the soil organic matter shared the greatest impact on the rice sustainable yield index (15.37%), followed by available nitrogen and available phosphorus. As such, there was the highest influencing level in the sustainable production of rice available phosphorus in the soil index, followed by available potassium and available nitrogen. Therefore, Fangzheng County should be focused on the soil available phosphorus in future rice production. While Ningxiang and Jinxian County should increase the soil available nitrogen and organic matter contents. [ABSTRACT FROM AUTHOR]

The rice, like other plants, undergoes photoprotection mode by increasing nonphotochemical quenching (NPQ) in high light intensity (> 1200 µmol m− 2s− 1 PPFD), which attenuates photosystem II yield (φPSII) drastically. The plant remains in photoprotection mode even after light intensity becomes not stressful for an extended period. While there are significant differences in the time it takes for photoprotection to recover among different genotypes, its use is limited in plant breeding because measuring the chlorophyll fluorescence parameters in progressive actinic light after dark adaptation takes more than forty-five minutes per genotype. The study finds that instantly measured A400/A1800 ratio by five minutes in flag leaves of 25 diverse genotypes strongly associated with the φPSII400 differences between theoretical and actual, qPd400 and NPQ400 with R2 values 0.74, 0.65 and 0.60, respectively. In two consecutive years, GWAS of A400/A1800 ratio identified the regions with genes reported earlier for plant photoprotection recovery. Additionally, QTL analysis in a RIL population also identified the regions carrying known genes related to photoprotection. Thus, the A400/A1800 ratio can quickly phenotype many plants for easier introgression of the traits in popular cultivars. The identified genotypes, genes, and QTLs can be used to improve yield potential and allele mining. [ABSTRACT FROM AUTHOR]

Summary CDKs are the master regulator of cell division and their activity is controlled by the regulatory subunit cyclins and phosphorylation by the CAKs. However, the role of MAP kinases in regulating plant cell cycle or CDKs have not been explored. Here, we report that the MAP kinases OsMPK3, OsMPK4, and OsMPK6 physically interact and phosphorylate OsCDKD and its regulatory subunit OsCYCH in rice. MAP kinases phosphorylate CDKD at Ser‐168 and Thr‐235 residues in OsCDKD. The MAP kinase‐mediated phosphorylation of OsCDKD is required for its activation to control the small RNA biogenesis. The phosphodead version of OsCDKD fails to activate the C‐terminal domain of RNA Polymerase II, thereby negatively impacting small RNA transcription. Further, the overexpression lines of wild‐type (WT) OsCDKD and phosphomimic OsCDKD show increased root growth, plant height, tiller number, panicle number, and seed number in comparison to WT, phosphodead OsCDKD‐OE, and kinase‐dead OsCDKD‐OE plants. In a nutshell, our study establishes a novel regulation of OsCDKD by MAPK‐mediated phosphorylation in rice. The phosphorylation of OsCDKD by MAPKs imparts a positive effect on rice growth and development by regulating miRNAs transcription. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in Samastipur district of Bihar, India during kharif season of 2021 and 2022 to identify suitable herbicides for control of composite weed flora in direct seeded rice. Compared to weedy check, application of bispyribac sodium + pyrazosulfuron ethyl as tank mixture effectively reduced weed density at 50 days after seeding during both the cropping season (82% and 86%, respectively) and weed dry weight (7.62 and 7.18 g m−2, respectively) over control and as a result yielded maximum during both the cropping season (47.92 and 51.32 q ha−1, respectively). Based on overall performance, bispyribac sodium + pyrazosulfuron ethyl may be considered as viable weed management option in direct seeded rice for the rice growers of middle Indo‐Gangetic region. [ABSTRACT FROM AUTHOR]

Summary Germination is a sustainable and economical process that can enhance the bioactivities of commonly consumed cereal and pulses, contributing to healthier diets. Its effectiveness in increasing bioactives depends on the germination conditions. This study examined the impact of varying germination periods (2, 4, 6, and 8 days) following 12 h of steeping on rice, maize, green gram, and soy, focusing on key bioactive compounds, including total polyphenols, flavonoids, and total digestible starch. Cereal and pulses germinated for eight days demonstrated a significantly higher (P < 0.05) total polyphenol and flavonoid content along with elevated antioxidant activity. Antioxidant activity strongly correlated to increased total polyphenol and flavonoid levels throughout the extended germination period. Moreover, the total digestible starch content (TDS) in rice, maize, and soy increased significantly (P < 0.05) because of the hydrolysis of starch molecules, while green gram showed twofold decrease in TDS, indicating the impact of germination on TDS content may differ across the type of cereal and pules. Using locally grown Sri Lankan grain varieties, such as rice, maize,green gram,and soy, this study fills the gap in existing database on the investigation of bioactive compounds and total digestible starch content, exploring the potential of germination of cereal and pulses to use in nutritionally rich products in the food and agriculture industry with a focus on sustainable food systems and healthier eating habits. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) plays an important role in maintaining or increasing soil fertility and quality in paddy field, but there is limited information about how SOC mineralization responds to different fertilizer managements under the double-cropping rice system in southern China. Therefore, this study was designed to explore changes in SOC content, soil enzyme activities, SOC mineralization at 0–10 cm and 10–20 cm layers, and its relationship with long-term fertilizer managements in a double-cropping rice system of southern China. The experiment included four fertilizer treatments: chemical fertilizer alone (CF), rice straw and chemical fertilizer (RS+F), 30% organic manure and 70% chemical fertilizer (OM+F), and without fertilizer input as a control (Con). These results showed that SOC and labile organic carbon contents at 0–10 cm and 10–20 cm layers in paddy field with RS+F and OM+F treatments were increased, compared to CF and Con treatments. Compared with Con treatment, SOC mineralization rate and accumulation with CF, RS+F, and OM+F treatments were increased. SOC accumulation and potential mineralization at 0–10 cm and 10–20 cm layers with RS+F and OM+F treatments were increased, compared with CF and Con treatments. SOC mineralization rate and accumulation at 0–10 cm layer with CF, RS+F, OM+F, and Con treatments were higher than that of 10–20 cm layer. These results indicated that soil invertase, cellulose and urease activities in paddy field with RS+F and OM+F treatments were significantly higher than that of CF and Con treatments. There was a significant positive relationship between SOC accumulation and SOC content, soil invertase, cellulose, urease activities but were significant negative correlated with soil pH, bulk density. As a result, these were beneficial practices for improving SOC content and SOC mineralization in a double-cropping rice field of southern China by combined application of rice residue or organic matter with chemical fertilizer managements. [ABSTRACT FROM AUTHOR]

Summary: The shape of rice grains not only determines the thousand‐grain weight but also correlates closely with the grain quality.Here we identified an ultra‐large grain accession (ULG) with a thousand‐grain weight exceeding 60 g. The integrated analysis of QTL, BSA, de novo genome assembled, transcription sequencing, and gene editing was conducted to dissect the molecular basis of the ULG formation.The ULG pyramided advantageous alleles from at least four known grain‐shaping genes, OsLG3, OsMADS1, GS3, GL3.1, and one novel locus, qULG2‐b, which encoded a leucine‐rich repeat receptor‐like kinase. The collective impacts of OsLG3, OsMADS1, GS3, and GL3.1 on grain size were confirmed in transgenic plants and near‐isogenic lines. The transcriptome analysis identified 112 genes cooperatively regulated by these four genes that were prominently involved in photosynthesis and carbon metabolism. By leveraging the pleiotropy of these genes, we enhanced the grain yield, appearance, and stress tolerance of rice var. SN265.Beyond showcasing the pyramiding of multiple grain size regulation genes that can produce ULG, our study provides a theoretical framework and valuable genomic resources for improving rice variety by leveraging the pleiotropy of grain size regulated genes. [ABSTRACT FROM AUTHOR]

Summary: Catalase (CAT) is the main reactive oxygen species (ROS)‐scavenging enzyme in plants and insects. However, it remains elusive whether and how insect saliva CAT suppresses ROS‐mediated plant defense, thereby promoting initial virus transmission by insect vectors.Here, we investigated how leafhopper Recilia dorsalis catalase (RdCAT) was secreted from insect salivary glands into rice phloem, and how it was perceived by rice chaperone NO CATALASE ACTIVITY1 (OsNCA1) to scavenge excessive H2O2 during insect‐to‐plant virus transmission.We found that the interaction of OsNCA1 with RdCAT activated its enzymatic activity to decompose H2O2 in rice plants during leafhopper feeding. However, initial insect feeding did not significantly change rice CATs transcripts. Knockout of OsNCA1 in transgenic lines decreased leafhopper feeding‐activated CAT activity and caused higher H2O2 accumulation. A devastating rice reovirus activated RdCAT expression and promoted the cosecretion of virions and RdCAT into leafhopper salivary cavities and ultimately into the phloem. Virus‐mediated increase of RdCAT secretion suppressed excessive H2O2, thereby promoting host attractiveness to insect vectors and initial virus transmission.Our findings provide insights into how insect saliva CAT is secreted and perceived by plant chaperones to suppress the early H2O2 burst during insect feeding, thereby facilitating viral transmission. [ABSTRACT FROM AUTHOR]

Summary: Cytoplasmic ribonucleoprotein (RNP) granules are membraneless structures composed of various RNAs and proteins that play important roles in post‐transcriptional regulation. While RNP granules are known to regulate the meiotic entry in some organisms, little is known about their roles in plants.In this study, we observed the cytoplasmic granular structures of rice RNA‐binding protein MEIOSIS ARRESTED AT LEPTOTENE2 (MEL2), which contributes to the control of meiotic entry timing, in leaf protoplasts and spore mother cells. We performed colocalization analysis with known cytoplasmic RNP factors, and domain deletion analysis to assess their impact on granule formation and meiosis progression. Conservation of MEL2 domains across plant species was also explored.Our results indicated that MEL2 granules colocalized with processing body and stress granule factors. The maintenance of granule properties modulated by LOTUS domain and the intrinsically disordered region (IDR) is essential for proper MEL2 function in meiosis progression. MEL2‐like proteins widely found in plant kingdom conserved LOTUS domain followed by the IDR despite their diverse domain structures, suggesting the functional conservation of these domains among plant species.This study highlights the role of MEL2 granule dynamics and its impact on meiotic transition and progression. [ABSTRACT FROM AUTHOR]

Summary: Gene silencing is crucial in crop breeding for desired trait development. RNA interference (RNAi) has been used widely but is limited by ectopic expression of transgenes and genetic instability. Introducing an upstream start codon (uATG) into the 5′untranslated region (5′UTR) of a target gene may 'silence' the target gene by inhibiting protein translation from the primary start codon (pATG).Here, we report an efficient gene silencing method by introducing a tailor‐designed uATG‐containing element (ATGE) into the 5′UTR of genes in plants, occupying the original start site to act as a new pATG.Using base editing to introduce new uATGs failed to silence two of the tested three rice genes, indicating complex regulatory mechanisms. Precisely inserting an ATGE adjacent to pATG achieved significant target protein downregulation. Through extensive optimization, we demonstrated this strategy substantially and consistently downregulated target protein expression. By designing a bidirectional multifunctional ATGE4, we enabled tunable knockdown from 19% to 89% and observed expected phenotypes. Introducing ATGE into Waxy, which regulates starch synthesis, generated grains with lower amylose, revealing the value for crop breeding.Together, we have developed a programmable and robust method to knock down gene expression in plants, with potential for biological mechanism exploration and crop enhancement. See also the Commentary on this article by Li & Wei, 243: 2052–2054. [ABSTRACT FROM AUTHOR]

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Heilongjiang, located in the cold region, is China's largest rice-producing and commercializing province. The variety selection of rice in cold regions (RCR) is indispensable in promoting the rice industry's development, and technological innovation in breeding theory plays a significant role in breeding breakthrough. Based primarily on long-term research, contemplation, and breeding practices, the 4S (selected topic, selected breeding, selected progenies, and selected promotion) phenotypic-design breeding technical system for RCR, which has revolutionized the theoretical basis and deepened the conceptual model, has been developed through systematic analyses and generalization. The system covers several key aspects such as scientific question formulation, breeding objective optimization, parental taxa hybridization, progeny population selection, and innovation dissemination, aiming to improve the foresight, precision, and efficiency of breeding. Furthermore, the system has demonstrated successful cases of rice variety breeding over the past 20 years, such as for Suijing 3, Suijing 4, Suijing 18, and a series of other rice varieties, providing theoretical and technical supports for cold-region rice breeding. [ABSTRACT FROM AUTHOR]

Crop nitrogen (N) and phosphorus (P) use efficiencies (NUE/PUE) are important to minimize wastage and nutrient pollution, but no improved crop for both is currently available. We addressed them together in rice, in the view of its high consumption of NPK fertilizers. We analyzed 46 morphophysiological parameters for the N/P response in three popular indica genotypes, namely, BPT 5204, Panvel 1, and CR Dhan 301 at low, medium, and normal N/P doses. They include 18 vegetative, 15 physiological, and 13 reproductive parameters. The segregation of significantly N/P-responsive parameters correlating with NUE/PUE revealed 21 NUE, 22 PUE, and 12 common parameters. Feature selection analyses revealed the common high-ranking parameters including the photosynthetic rate at the reproductive stage, tiller number, root–shoot ratio, culm thickness, and flag leaf width. The venn selection using the reported NUE/PUE-related candidate genes in rice revealed five genes in common for both, namely OsIAA3, OsEXPA10, OsCYP75B4, OsSultr3;4, and OsFER2, which were associated with three of the common traits for NUE/PUE. Their expression studies using qRT-PCR revealed the opposite regulation in contrasting genotypes for OsSultr3;4 and OsEXPA10 in N-response and for OsFER2 in P-response, indicating their role in contrasting N/P use efficiencies. Overall, CR Dhan 301 has the highest NUE and PUE followed by Panvel 1 and BPT5204 among the studied genotypes. [ABSTRACT FROM AUTHOR]

Rational nitrogen (N) application can enhance yield and improve grain eating quality in rice. However, excessive N input can deteriorate grain eating quality and aggravate environmental pollution, while reduced N application (RN) decreases rice yield. Reduced N application with dense planting (RNDP) is recommended for maintaining rice yield and improving N use efficiency. However, the effects of RNDP on the rice grain eating quality and starch structure and properties remain unclear. A two-year field experiment was conducted to investigate the effects of RNDP on the rice yield, grain eating quality, and starch structure and properties. Compared to conventional N treatment, RN decreased significantly the rice yield, while RNDP achieved a comparable grain yield. Both the RN and RNDP treatments improved significantly the rice eating quality. The high eating quality of RNDP was attributed to increased gel consistency, pasting viscosity, and stickiness after cooking as well as decreased protein content. A further analysis of starch structure and properties revealed that RNDP decreased the relative crystallinity, lamellar intensity, gelatinization enthalpy, and retrogradation enthalpy of starch. Therefore, RNDP achieved a stable rice yield and enhanced rice eating quality. These findings provide valuable insights into obtaining optimal quality and consistent yield in rice production under reduced N conditions. [ABSTRACT FROM AUTHOR]

A low temperature (LT) is used to delay grain deterioration effectively. In practical applications, a nitrogen-modified atmosphere (N2) is also an effective way of preventing grain pests and delaying grain deterioration. However, there are few studies on grain quality changes using a combination treatment of an LT and N2 during storage. In this study, the storage quality, processing characteristics, and metabolites of rice under conventional storage (CS), LT (20 °C), N2 (95%), and LT+N2 treatments were analyzed for 180 days, under a controlled humidity of 65% ± 2%. The results showed that compared to the CS, LT, and N2 treatments, the LT+N2 treatment had the best effect in retarding the increase in MDA and electrical conductivity and deferring the decrease in CAT activity. In addition, the LT+N2 treatment maintained the color of the rice better and sustained a better processing quality. Non-targeted metabolomics analysis further confirmed that the LT+N2 treatment maintained the vigor of the rice and retarded its spoilage by activating the metabolisms of amino acids, carbohydrates, and flavonoids. These results suggest a favorable practice for preventing storage deterioration and increasing the processing quality for rice storage. They provided new insights into the mechanisms of rice quality changes using the combination treatment of an LT and N2. [ABSTRACT FROM AUTHOR]

Harvest time is very important to rice due to its high correlation to rice yield, eating quality, etc.; however, the impact of harvest time on quality is still unclear. In this study, Nangeng 5718, a japonica rice planted in three regions in Jiangsu Province of China, was used to analyze and compare the milling quality, appearance quality, and physicochemical quality of japonica rice at different harvest times. The results showed that the 1000-grain weight of Nangeng 5718 exhibited no significant change at different harvest times (p > 0.05). The brown rice rate and rice yield at different harvest times were 82.3–85.4% and 66.3–76.1%, respectively. Harvest time had no significant effect on the brown of rice (p > 0.05). However, Nangeng 5718 planted in Nanjing had the highest rice yield at 50 days after heading, which was significantly different from that of rice harvested 65 days after heading (p < 0.05). Nangeng 5718 planted in Huai'an had the highest rice yield at 55 days after heading, which was significantly different from that of rice harvested 60 days after heading (p < 0.05). Harvest time had little effect on the length, width, and thickness of rice. The immature grain rate showed a decreasing trend with the increase in maturity. There were little differences in the protein content of Nangeng 5718 at different harvest times. Nangeng 5718 planted in Nanjing had the highest protein content at 50 days after heading. There was a significant difference between the rice harvested and the rice harvested 60 days after heading (p < 0.05). There were no significant differences between the other two regions (p > 0.05). The accumulated temperature in Nanjing was relatively high, and the RVA curve and RVA eigenvalues of rice varied greatly. The setback value of rice harvested at 50 days was significantly lower than that at 55 days and 60 days (p < 0.05). Rice has good gelatinizing properties. Therefore, timely harvesting and appropriate accumulated temperature could increase 1000-grain weight and rice yield, reduce the immature grain rate, and improve the gelatinization characteristics. Overall, the quality of Nangeng 5718 reached a good level when it was harvested 50 days after heading, with the accumulated temperature reaching 1051 °C. In fact, the harvest time should be chosen flexibly according to the weather conditions. Nangeng 5718 planted in Nanjing should be harvested earlier than 50 days, and rice from Huai'an and Lianyungang was of better quality when the harvest time was 50 days. [ABSTRACT FROM AUTHOR]

Soil salinity pollution is increasing worldwide, seriously affecting plant growth and crop production. Existing reports on how potassium indole-3-butyric acid (IBAK) regulates rice salt stress adaptation by affecting rice carbon metabolism, transcription factor (TF) genes expression, and biosynthesis of secondary metabolites still have limitations. In this study, an IBAK solution at 40 mg L-1 was sprayed on rice leaves at the seedling stage. The results showed that the IBAK application could promote shoot and root growth, decrease sucrose and fructose content, increase starch content, and enhance acid invertase (AI) and neutral invertase (NI) activity under salt stress, indicating altered carbon allocation. Furthermore, the expression of TF genes belonging to the ethylene responsive factor (ERF), WRKY, and basic helix-loop-helix (bHLH) families was influenced by IBAK. Many key genes (OsSSIIc, OsSHM1, and OsPPDKB) and metabolites (2-oxoglutaric acid, fumaric acid, and succinic acid) were upregulated in the carbon metabolism pathway. In addition, this study highlighted the role of IBAK in regulating the biosynthesis of secondary metabolites pathway, potentially contributing to rice stress adaptability. The results of this study can provide new sustainable development solutions for agricultural production. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a well-known pollutant in agricultural soil, affecting human health through the food chain. To combat this issue, Ca + Mg (25 mg L-1) nanocomposite and Bacillus pumilus, either alone or combined, were applied to rice plants under Cd (5 mg kg-1, 10 mg kg-1) contamination. In our study, growth and yield traits demonstrated the beneficial influence of Ca + Mg and B. pumilus application in improving rice defense mechanism by reducing Cd stress. Combined Ca + Mg and B. pumilus application increased SPAD (15), total chlorophyll (18), chlorophyll a (11), chlorophyll b (22), and carotenoids (21%) with Cd (10 mg kg-1), compared to the application alone. Combined Ca + Mg and B. pumilus application significantly regulated MDA (15), H2O2 (13), EL (10), and O2 •- (24%) in shoots under Cd (10 mg kg-1), compared to the application alone. Cd (10 mg kg-1) increased the POD (22), SOD (21), APX (12), and CAT (13%) in shoots with combined Ca + Mg and B. pumilus application, compared to the application alone. Combined Ca + Mg and B. pumilus application significantly reduced Cd accumulation in roots (22), shoots (13), and grains (20%) under Cd (10 mg kg-1), compared to the application alone. Consequently, the combined application of Ca + Mg and B. pumilus is a sustainable solution to enhance crop production under Cd stress. [ABSTRACT FROM AUTHOR]

Carbon farming has become increasingly popular as it integrates agriculture, forestry, and diverse land use practices, all crucial for implementing European strategies aimed at capturing 310 million tons of carbon dioxide from the atmosphere. These farming methods were proven to reliably increase the amount of carbon stored in the soil. However, there is a lack of discussion and consensus regarding the standards used to report these values and their implications. This article analyzes carbon sequestration rates, calculation methodologies, and communication procedures, as well as potential co-benefits and best practices. The average carbon sequestration rates in major staple crops range from very low values (0–0.5 Mg/ha/yr) to medium values (1–5 Mg/ha/yr). Scientific agricultural experiments in key global staple crops demonstrate positive rates of 4.96 Mg C ha−1 yr−1 in wheat–maize rotations and 0.52–0.69 Mg C ha−1 yr−1 in rice–wheat rotations. In agriculture, carbon sequestration rates are reported using different terms that are not consistent and pose communication challenges. This assessment involves a systematic review of the scientific literature, including articles, reviews, book chapters, and conference papers indexed in Scopus from 2001 to 2022. Specifically, this review focuses on long-term experiments, meta-analyses, and reviews that report an increase in soil carbon stock. The research trends observed, through a VOSviewer 1.6.18 analysis, show a steadily increasing interest in the field of carbon sequestration. [ABSTRACT FROM AUTHOR]

The transcription factor WRKYs play pivotal roles in the adapting to adverse environments in plants. Prior research has demonstrated the involvement of OsWRKY70 in resistance against herbivores and its response to abiotic stress. Here, we reported the functional analysis of OsWRKY70 in immunity against fungal diseases and cold tolerance. The results revealed that OsWRKY70 was induced by various Magnaporthe oryzae strains. Knock out mutants of OsWRKY70, which were generated by the CRISPR/Cas9 system, exhibited enhanced resistance to M. oryzae. This was consistent with fortifying the reactive oxygen species (ROS) burst after inoculation in the mutants, elevated transcript levels of defense-responsive genes (OsPR1b, OsPBZ1, OsPOX8.1 and OsPOX22.3) and the observation of the sluggish growth of invasive hyphae under fluorescence microscope. RNA sequencing (RNA-seq) and quantitative real-time PCR (qRT-PCR) validations demonstrated that differentially expressed genes were related to plant-pathogen interactions, hormone transduction and MAPK cascades. Notably, OsbHLH6, a key component of the JA signaling pathway, was down-regulated in the mutants compared to wild type plants. Further investigation confirmed that OsWRKY70 bound to the promoter of OsbHLH6 by semi-in vivo chromatin immunoprecipitation (ChIP). Additionally, the loss-function of OsWRKY70 impaired cold tolerance in rice. The enhanced susceptibility in the mutants characterized by excessive ROS production, elevated ion leakage rate and increased malondialdehyde content, as well as decreased activity of catalase (CAT) and peroxidase (POD) under low temperature stress was, which might be attributed to down-regulation of cold-responsive genes (OsLti6b and OsICE1). In conclusion, our findings indicate that OsWRKY70 negatively contributes to blast resistance but positively regulates cold tolerance in rice, providing a strategy for crop breeding with tolerance to stress. [ABSTRACT FROM AUTHOR]

The functionalization of aromatic N‐heterocycles through silylium activation demonstrates exceptional selectivity and efficiency. Density functional theory (DFT) calculations unveil the detailed silylium catalysis mechanism and elucidate the origins of selectivity in this reaction. The phosphoramidimidate sulfonamide (PADI) precatalyst orchestrates of the catalytic cycle via three elementary steps. The Brønsted acidity of precatalyst significantly influences both the formation of silylium‐based Lewis acid active species and the silylium activation of pyridine. Unlike disulfonimide (DSI)‐type precatalysts, both Tf2NH and PADI precatalysts with strong acidities can easily promote the generation of activated silylium pyridine species. A semi‐enclosed ′rigid' electronegative cavity in PADI‐type anions constructs a well‐defined recognition site, facilitating engagement with the positively charged silylium pyridine species. Due to the high electrophilicity and less steric demand at the C4‐position of the pyridine substrate, the product with C4‐regioselectivity was predominantly generated. [ABSTRACT FROM AUTHOR]

Phosphorus (P) and potassium (K) affect seedling growth, root configuration, and nutrient uptake in hydroponic rice, but there are few studies on all growth stages of rice. The purpose of this experiment was to determine the response characteristics of root morphology, plant physiology, and P and K uptake and utilization efficiency to different supplies of P and K. Two local conventional rice varieties (Shennong 265 and Liaojing 294) were used as experimental materials across four treatments, including HPHK (sufficient P and K supply), HPLK (sufficient P supply under low K levels), LPHK (sufficient K supply under low P levels) and LPLK (low P and K levels) in a hydroponic setting. The results showed that HPHK and HPLK significantly decreased the acid phosphatase activity of leaves and roots from full heading to filling stages when compared to LPHK and LPLK. Sufficient supply of P or K significantly increased the accumulation of P and K (aboveground, leaves, stem sheath, and whole plant) and root morphological parameters (root length, root surface area, total root volume, and tips) during major growth stages when compared to LP or LK levels. HPHK was significantly higher than other treatments in terms of dry weight and the root activity at the main growth stage, P and K uptake rates in nutrient solutions at various stages, related P and K efficiency at the maturity stage, yield, effective panicle number, and grain number per panicle. In addition, the effect of HPHK on the above indexes were significantly greater than those of single sufficient supply of P or K. In conclusion, HPHK can improve plant configuration, increase plant P and K absorption and root activity, and increase rice yield and related P and K utilization efficiency. [ABSTRACT FROM AUTHOR]

This study demonstrated the plant growth-promoting capabilities of native actinobacterial strains obtained from different regions of the rice plant, including the rhizosphere (FT1, FTSA2, FB2, and FH7) and endosphere (EB6). We delved into the molecular mechanisms underlying the beneficial effects of these plant-microbe interactions by conducting a transcriptional analysis of a select group of key genes involved in phytohormone pathways. Through in vitro screening for various plant growth-promoting (PGP) traits, all tested isolates exhibited positive traits for indole-3-acetic acid synthesis and siderophore production, with FT1 being the sole producer of hydrogen cyanide (HCN). All isolates were identified as members of the Streptomyces genus through 16S rRNA amplification. In pot culture experiments, rice seeds inoculated with strains FB2 and FTSA2 exhibited significant increases in shoot dry mass by 7% and 34%, respectively, and total biomass by 8% and 30%, respectively. All strains led to increased leaf nitrogen levels, with FTSA2 demonstrating the highest increase (4.3%). On the contrary, strains FB2 and FT1 increased root length, root weight ratio, root volume, and root surface area, leading to higher root nitrogen content. All isolates, except for FB2, enhanced total chlorophyll and carotenoid levels. Additionally, qRT-PCR analysis supported these findings, revealing differential gene expression in auxin (OsAUX1, OsIAA1, OsYUCCA1, OsYUCCA3), gibberellin (OsGID1, OsGA20ox-1), and cytokinin (OsIPT3, OsIPT5) pathways in response to specific actinobacterial treatments. These actinobacterial strains, which enhance both aboveground and belowground crop characteristics, warrant further evaluation in field trials, either as individual strains or in consortia. This could lead to the development of commercial bioinoculants for use in integrated nutrient management practices. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION High temperature stress (HTS) has become a serious threat to rice grain quality and few studies have examined the effects of HTS across multiple stages on rice grain quality. In the present study, we conducted 2 years of HTS treatments under three temperature regimes (32/22 °C, 40/30 °C and 44/34 °C) and HTS durations of 2 days and 4 days at three critical stages: booting, flowering, and a combination of booting and flowering. We employed the heat degree days (HDD) metric, which accounts for both the level and duration of HTS, to quantify the relationships between grain quality traits and HTS.The results revealed the diverse effects of HTS on rice grain quality at different stages, durations and temperature levels. HTS significantly (P < 0.05) reduced grain quality, with the highest sensitivities (reduction per 1 °C day−1 increase in HDD) observed at the flowering stage, followed by the combined and booting stages treatments under mild HTS treatment (40/30 °C). However, under extreme HTS treatments (44/34 °C) for 4 days, rice grains subjected to combined HTS treatment experienced complete mortality.Pre‐exposed to HTS at the booting stage within a certain intensity can alleviate the adverse effects of post‐flowering HTS on grain quality. This provides valuable insights for assessing the potential impact of multiple HTS events on the grain quality under future climate warming. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

ABSTRACT Heat stress at the flowering stage significantly impacts rice grain yield, yet the number of identified genes associated with rice heat tolerance at this crucial stage remains limited. This study focuses on elucidating the function of the heat‐induced gene reduced heat stress tolerance 1 (OsRHS). Overexpression of OsRHS leads to reduced heat tolerance, while RNAi silencing or knockout of OsRHS enhances heat tolerance without compromising yield, as assessed by the seed setting rate. OsRHS is localized in the cytoplasm and mainly expressed in the glume and anther of spikelet. Moreover, OsRHS was found to interact with the HSP protein cHSP70‐4, and the knockout of cHSP70‐4 resulted in increased heat tolerance. Complementation assays revealed that the knockout of cHSP70‐4 could restore the compromised heat tolerance in OsRHS overexpression plants. Additional investigation reveals that elevated temperatures can amplify the bond between OsRHS and cHSP70‐4 within rice. Furthermore, our findings indicate that under heat stress conditions during the flowering stage, OsRHS plays a negative regulatory role in the expression of many stress‐related genes. These findings unveil the crucial involvement of OsRHS and cHSP70‐4 in modulating heat tolerance in rice and identify novel target genes for enhancing heat resilience during the flowering phase in rice. [ABSTRACT FROM AUTHOR]

The identification effector targets and characterization of their functions are crucial for understanding pathogen infection mechanisms and components of plant immunity. Here, we identify the effector UgsL, a ustilaginoidin synthetase with a key role in regulating virulence of the rice false smut fungus Ustilaginoidea virens. Heterologous expression of UgsL in rice (Oryza sativa) enhances plant susceptibility to multiple pathogens, and host-induced gene silencing of UgsL enhances plant resistance to U. virens, indicating that UgsL inhibits rice immunity. UgsL interacts with STRUBBELIG RECEPTOR KINASE 3 (OsSRF3). Genome editing and overexpression of OsSRF3 demonstrate that OsSRF3 plays a pivotal role in the resistance of rice to multiple pathogens. Remarkably, overexpressing OsSRF3 enhances resistance without adversely affecting plant growth or yield. We show that BRASSINOSTEROID RECEPTOR-ASSOCIATED KINASE 1 (OsBAK1) interacts with and phosphorylates OsSRF3 to activate pathogen-triggered immunity, inducing the mitogen-activated protein kinase cascade, a reactive oxygen species burst, callose deposition, and expression of defense-related genes. UgsL interferes with the phosphorylation of OsSRF3 by OsBAK1. Furthermore, UgsL mediates OsSRF3 degradation by facilitating its association with the ubiquitin-26S proteasome. Our results reveal that OsSRF3 positively regulates immunity in rice and that UgsL mediates its degradation, thereby inhibiting the activation of OsBAK1–OsSRF3-mediated immune pathways. The Ustilaginoidea virens effector UgsL is shown to interact with receptor kinase OsSRF3. OsSRF3 positively regulates immunity in rice and UgsL mediates its degradation, thereby inhibiting the activation of OsBAK1–OsSRF3-mediated immune responses in rice. [ABSTRACT FROM AUTHOR]

Introduction: Owing to advances in high-throughput genome sequencing, QTLSeq mapping of salt tolerance traits is a major platform for identifying soil-salinity tolerance QTLs to accelerate marker-assisted selection for salt-tolerant rice varieties. We performed QTL-BSA-Seq in the seedling stage of rice from a genetic cross of the extreme salt-sensitive variety, IR29, and "Jao Khao" (JK), a Thai salt-tolerant variety. Methods: A total of 462 F2 progeny grown in soil and treated with 160 mM NaCl were used as the QTL mapping population. Two high- and low-bulk sets, based on cell membrane stability (CMS) and tiller number at the recovery stage (TN), were equally sampled. The genomes of each pool were sequenced, and statistical significance of QTL was calculated using QTLseq and G prime (G') analysis, which is based on calculating the allele frequency differences or D(SNP index). Results: Both methods detected the overlapping interval region, wherein CMSbulk was mapped at two loci in the 38.41-38.85 Mb region with 336 SNPs on chromosome 1 (qCMS1) and the 26.13-26.80 Mb region with 1,011 SNPs on chromosome 3 (qCMS3); the D(SNP index) peaks were -0.2709 and 0.3127, respectively. TN-bulk was mapped at only one locus in the overlapping 38.26-38.95 Mb region on chromosome 1 with 575 SNPs (qTN1) and a D(SNP index) peak of -0.3544. These identified QTLs in two different genetic backgrounds of segregating populations derived from JK were validated. The results confirmed the colocalization of the qCMS1 and qTN1 traits on chromosome 1. Based on the CMS trait, qCMS1/qTN1 stably expressed 6%-18% of the phenotypic variance in the two validation populations, while qCMS1/qTN1 accounted for 16%-20% of the phenotypic variance in one validation population based on the TN trait. Conclusion: The findings confirm that the CMS and TN traits are tightly linked to the long arm of chromosome 1 rather than to chromosome 3. The validated qCMS-TN1 QTL can be used for gene/QTL pyramiding in marker-assisted selection to expedite breeding for salt resistance in rice at the seedling stage. [ABSTRACT FROM AUTHOR]

In order to screen suitable winter covering crops for rice cultivation in Hubei region, field experiments were conducted in Wuhan, Hubei to study the effects of different winter covering crops on rice yield, nutrients, and soil nutrient content. The results showed that winter planting of covered crops could promote rice yield by 6. 95%-12. 91%, and planting green manure in winter was more conducive to improving rice yield than returning rapeseed straw to the field to a certain extent. Winter covering crops mainly affected the number of grains per panicle of rice, which could improve the dry matter quality of rice by 12. 15%-18. 22%, increase nitrogen accumulation by 3. 44%-13. 66%, and potassium accumulation by 3. 17%-11. 12%. Returning straw to the field had a significant effect on increasing potassium accumulation in rice. Winter covering crops could increase the activity of urease, phosphatase, and invertase in the rhizosphere soil during the rice harvest period, resulting in an increase of 3. 42%-7. 92%, 2. 81%-21. 77%, and 2. 05%-8. 55% in the alkaline hydrolyzed nitrogen, available phosphorus, and available potassium content of the soil after rice harvest. Planting rapeseed and rice in a fertile field had the highest alkaline hydrolyzed nitrogen and available phosphorus content in the soil after rice harvest, while straw returning had the highest available potassium content in the soil. [ABSTRACT FROM AUTHOR]

A total of 10 kinds of commercialized soil conditioner products of common brands on the market and soil conditioner products compounded by universities and scientific research institutes were selected to carry out field tests in mercury-polluted paddy fields in Jiangning District of Nanjing, to explore the effects of these 10 soil conditioners on soil pH, soil mercury, soil nutrients and Hg content in rice grains. The results showed that compared with the control, the use of soil conditioner could improve soil pH, reduce soil mercury content and rice grain Hg content to some extent. At the same time, the application of soil conditioner could also effectively improve the content of soil organic matter, available phosphorus and available potassium, and reduce the content of alkali-hydrolyzable nitrogen. The mercury enrichment coefficient of rice could be reduced by different soil conditioners, with a decrease of 19. 0%-62. 6%. Among them, organic sulfur improver had a higher reduction in grain BCF, followed by clay mineral-based soil conditioner and calcium silicate soil conditioner. [ABSTRACT FROM AUTHOR]

Background: Squamosa promoter-binding protein-like (SPL) is a plant-specific transcription factor that is widely involved in the regulation of plant growth and development, including flower and grain development, stress responses, and secondary metabolite synthesis. However, this gene family has not been comprehensively evaluated in barley, the most adaptable cereal crop with a high nutritional value. Results: In this study, a total of 15 HvSPL genes were identified based on the Hordeum vulgare genome. These genes were named HvSPL1 to HvSPL15 based on the chromosomal distribution of the HvSPL genes and were divided into seven groups (I, II, III, V, VI, VII, and VIII) based on the phylogenetic tree analysis. Chromosomal localization revealed one pair of tandem duplicated genes and one pair of segmental duplicated genes. The HvSPL genes exhibited the highest collinearity with the monocotyledonous plant, Zea mays (27 pairs), followed by Oryza sativa (18 pairs), Sorghum bicolor (16 pairs), and Arabidopsis thaliana (3 pairs), and the fewest homologous genes with Solanum lycopersicum (1 pair). The distribution of the HvSPL genes in the evolutionary tree was relatively scattered, and HvSPL proteins tended to cluster with SPL proteins from Z. mays and O. sativa, indicating a close relationship between HvSPL and SPL proteins from monocotyledonous plants. Finally, the spatial and temporal expression patterns of the 14 HvSPL genes from different subfamilies were determined using quantitative real-time polymerase chain reaction (qRT-PCR). Based on the results, the HvSPL gene family exhibited tissue-specific expression and played a regulatory role in grain development and abiotic stress. HvSPL genes are highly expressed in various tissues during seed development. The expression levels of HvSPL genes under the six abiotic stress conditions indicated that many genes responded to stress, especially HvSPL8, which exhibited high expression under multiple stress conditions, thereby warranting further attention. Conclusion: In this study, 15 SPL gene family members were identified in the genome of Hordeum vulgare, and the phylogenetic relationships, gene structure, replication events, gene expression, and potential roles of these genes in millet development were studied. Our findings lay the foundation for exploring the HvSPL genes and performing molecular breeding of barley. [ABSTRACT FROM AUTHOR]

Rice is one of the major food crops grown globally. However, during the wet season, rice suffers significant yield loss due to reduced light intensity caused by overcast clouds when the light intensity is only around 450–500 µmol/m2/s, compared to 1400–1800 µmol/m2/s in summer. This reduction in light intensity leads to a decrease in seed yield, mainly by limiting tiller or panicle numbers. Yield and its attributing parameters were recorded in one hundred thirty RILs for four consecutive wet seasons in ambient light (AL) and low light (LL, 35% light-cut using white shade net). QTL analysis was performed using Inclusive Composite Interval Mapping (ICIM) with all the phenotypic data and 927 polymorphic SNPs identified by the 7 K Infinium chip. The study identified a large QTL influencing panicle numbers and yield exclusively in lowlight on chromosome 1 (qPNLL1.1, qGYLL1.1) in four consecutive seasons with LOD > 10 and PVE > 30%. The favourable alleles are from the tolerant parent, Swarnaprabha. Another grain yield improving QTL was identified on chromosome 6 (qGYLL6.1), with LOD > 3 in three consecutive seasons. In a diverse rice panel of one hundred seventeen genotypes with five different models, association analysis identified the associated marker for panicle numbers and grain yield in LL, which is also the left marker of the newly identified QTLs for the traits under LL condition. A shade-responsive gene, monoculm 2 (MOC2, LOC_Os01g64660) inside the QTL on chromosome 1, upregulated in the tolerant parent and its QTL-carrying RILs, whereas repressed in the susceptible one. Therefore, due to its significant additive effect and validation across various genotypes, the yield-improving QTL on chromosome 1 can be directly utilised in marker-assisted selection (MAS) for developing shade-tolerant rice. This can also help reduce the yield gap between wet and dry-season rice. [ABSTRACT FROM AUTHOR]

Nitrogen is an essential nutrient for plants and a major determinant of plant growth and crop yield. Plants acquire nitrogen mainly in the form of nitrate and ammonium. Both nitrogen sources affect plant responses and signaling pathways in a different way, but these signaling pathways interact, complicating the study of nitrogen responses. Extensive transcriptome analyses and the construction of gene regulatory networks, mainly in response to nitrate, have significantly advanced our understanding of nitrogen signaling and responses in model plants and crops. In this study, we aimed to generate a more comprehensive gene regulatory network for the major crop, rice, by incorporating the interactions between ammonium and nitrate. To achieve this, we assessed transcriptome changes in rice roots and shoots over an extensive time course under single or combined applications of the two nitrogen sources. This dataset enabled us to construct a holistic co-expression network and identify potential key regulators of nitrogen responses. Next to known transcription factors, we identified multiple new candidates, including the transcription factors OsRLI and OsEIL1, which we demonstrated to induce the primary nitrate-responsive genes OsNRT1.1b and OsNIR1. Our network thus serves as a valuable resource to obtain novel insights in nitrogen signaling. [ABSTRACT FROM AUTHOR]

AbstractEmploying nanoscale materials as fertilizers through foliar applications in agriculture has been on the rise and is one of the effective methods for sustainable agriculture. Herein, we investigated the effects of foliar sprays of varied concentrations (@ 100, 200,400, 600, 800, and 1000 ppm) of nanoscale silica on the productivity of rice (field scale) during two rabi seasons (2021–22 and 2022–23). The modified Stober method was used to prepare SiNPs and characterized using particle size analyzer and transmission electron microscopy. The recorded average size of SiNPs was 28.8 nm, with a positive zeta potential (24.6 mV). Pooled results revealed that RDF + foliar spray of SiNPs at 200 ppm increased the culm diameter of rice by 13.6 and 14.3 per cent over silicic acid (@ 4000 ppm) and RDF, respectively. Grain yield (5905 kg ha−1) and straw yield (7517 kg ha−1) were increased by 45.53 and 45.73 per cent over silicic acid (4058 kg ha−1 of grain yield; 5158 kg ha−1 of straw yield) treatments, respectively. Foliar application of SiNPs @ 200 ppm along with RDF significantly increased the protein content of grain (8.82%) and recorded higher net returns of 88506.15 ha−1 with benefit-cost ratio of 2.68 over other treatments tested. [ABSTRACT FROM AUTHOR]