To explore how rice(Oryza sativa L.) can be safely produced in Cd-polluted soil, OsLCT1 and OsNramp5 mutant lines were generated by CRISPR/Cas9-mediated mutagenesis. One of OsLCT1 mutant(lct1×1) and two of OsNram...To explore how rice(Oryza sativa L.) can be safely produced in Cd-polluted soil, OsLCT1 and OsNramp5 mutant lines were generated by CRISPR/Cas9-mediated mutagenesis. One of OsLCT1 mutant(lct1×1) and two of OsNramp5 mutants(nramp5×7 and nramp5×9) were evaluated for grain Cd accumulation and agronomic performances. In paddy field soil containing approximately 0.9 mg/kg Cd, lct1×1 grains contained approximately 40%(0.17 mg/kg) of the Cd concentration of the wild type parental line, less than the China National Food Safety Standard(0.20 mg/kg). Both OsNramp5 mutants showed low grain Cd accumulation(< 0.06 mg/kg) in the paddy(approximately 0.9 mg/kg Cd) or in pots in soil spiked with 2 mg/kg Cd. However, only nramp5×7 showed normal growth and yield, whereas the growth of nramp5×9 was severely impaired. The study showed that lct1×1 could be used to produce rice grains safe for human consumption in lightly contaminated paddy soils and nramp5×7 used in soils contaminated by much higher levels of Cd.展开更多
Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamb...Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30℃/24℃day/night)under natural sunlight conditions with different nutrient regimes.The results showed that N had the strongest influence on the plant growth and development,followed by P and K.The highest nonstructural carbohydrate content,dry matter weight,net photosynthetic rate(Pn),ATP content,as well as NADH dehydrogenase,cytochrome oxidase and ATPase activities were found in the plants that received sufficient N,P and K.The lowest values of these parameters were detected in the N-deficient plants.Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments,but there was no significant difference in the ratio of respiration rate to Pn between these two treatments,suggesting that differences in energy production efficiency may have accounted for this result.This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase,cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants.We therefore inferred different abilities in energy production efficiency among N,P and K in rice seedlings,which determined rice plant growth and development.展开更多
Fifteen common rice maintainer lines and 26 high-yielding restorer lines were used to evaluate their thermal resistance and fertility during flowering and early grain filling stages. The rice plants were subjected to ...Fifteen common rice maintainer lines and 26 high-yielding restorer lines were used to evaluate their thermal resistance and fertility during flowering and early grain filling stages. The rice plants were subjected to high temperature stress （39-43 ℃） for 1-15 d from main stem flowering. Based on the heat stress index, they were divided into thermal resistant lines, semi-thermal resistant lines, semi-thermal sensitive lines and thermal sensitive lines. Therefore, the maintainer lines K22B, Bobai B and V20B belonged to thermal resistant lines, whereas 11-32B, Zhongzhe B and Zhong 9B belonged to thermal sensitive lines. For rice restorer lines, Minghui 63 had the highest thermal resistance, followed by R207, P32, P929, and the lowest thermal resistant lines P62-2-2, R8006 and P51. The correlation analysis indicated that the heat stress index was significantly correlated with seed-setting rate and abortive grain rate under heat stress, but not under natural conditions. This indicated that heat stress occurred during flowering and early grain filling stages mainly decreased the seed- setting rate and significantly increased the abortive grain rate in both rice maintainer and restorer lines.展开更多
Rice grain shape, grain length （GL）, width （GW）, thickness （GT） and length-to-width ratio （LWR）, are usually controlled by multiple quantitative trait locus （QTL）. To elucidate the genetic basis of extremely...Rice grain shape, grain length （GL）, width （GW）, thickness （GT） and length-to-width ratio （LWR）, are usually controlled by multiple quantitative trait locus （QTL）. To elucidate the genetic basis of extremely large grain shape, QTL analysis was performed using an F2 population derived from a cross between a japonica cuttivar ＇JZI560＇ （extremely large grain） and a contrasting indica cultivar ＇FAZI＇ （small grain）. A total number of 24 QTLs were detected on seven different chromosomes. QTLs for GL, GW, GT and LWR explained 11.6%, 95.62%, 91.5% and 89.9% of total phenotypic variation, respectively. Many QTLs pleiotropically controlled different grain traits, contributing complex traits correlation. GW2 and qSW5/GW5, which have been cloned previously to control GW, showed similar chromosomal locations with qGW2-1/qGT2-1/qLWR2-2 and qGW5-2/qLWR5-1 and should be the right candidate genes. Plants pyramiding GW2 and qSW5/GW5 showed a significant increase in GW compared with those carrying one of the two major QTLs. Furthermore, no significant QTL interaction was observed between GW2 and qSW5/GW5. These results suggested that GW2 and qSW5/GW5 might work in independent pathways to regulate grain traits. ＇JZ1560＇ alleles underlying all QTLs contributed an increase in GW and GT and the accumulation of additive effects generates the extremely large grain shape in ＇JZ1560＇.展开更多
Mutation breeding is based on the induction of genetic variations; hence knowledge of the frequency and type of induced mutations is of paramount importance for the design and implementation of a mutation breeding pro...Mutation breeding is based on the induction of genetic variations; hence knowledge of the frequency and type of induced mutations is of paramount importance for the design and implementation of a mutation breeding program. Although γ ray irradiation has been widely used since the 1960 s in the breeding of about 200 economically important plant species, molecular elucidation of its genetic effects has so far been achieved largely by analysis of target genes or genomic regions. In the present study, the whole genomes of six γ-irradiated M2 rice plants were sequenced; a total of 144–188 million high-quality（Q〉20） reads were generated for each M2 plant, resulting in genome coverage of 45 times for each plant. Single base substitution（SBS） and short insertion/deletion（Indel） mutations were detected at the average frequency of 7.5×10^-6～9.8×10^-6 in the six M2 rice plants（SBS being about 4 times more frequent than Indels）. Structural and copy number variations, though less frequent than SBS and Indel, were also identified and validated. The mutations were scattered in all genomic regions across 12 rice chromosomes without apparent hotspots. The present study is the first genome-wide single-nucleotide resolution study on the feature and frequency of γ irradiation-induced mutations in a seed propagated crop; the findings are of practical importance for mutation breeding of rice and other crop species.展开更多
Targeting Induced Local Lesions IN Genomes （TILLING） is a reverse genetics strategy for the high-throughput screening of induced mutations.γ, radiation, which often induces both insertion/deletion （Indel） and poi...Targeting Induced Local Lesions IN Genomes （TILLING） is a reverse genetics strategy for the high-throughput screening of induced mutations.γ, radiation, which often induces both insertion/deletion （Indel） and point mutations, has been widely used in mutation induction and crop breeding. The present study aimed to develop a simple, high-throughput TILLING system for screening γ ray-induced mutations using high-resolution melting （HRM） analysis. Pooled rice （Oryza sativa） samples mixed at a 1：7 ratio of Indel mutant to wild-type DNA could be distinguished from the wild-type controls by HRM analysis. Thus, an HRM-TILLING system that analyzes pooled samples of four M2 plants is recommended for screening γ, ray-induced mutants in rice. For demonstration, a γ, ray-mutagenized M2 rice population （n=4560） was screened for mutations in two genes, OsLCT1 and SPDT, using this HRM-TILLING system. Mutations including one single nucleotide substitution （G→A） and one single nucleotide insertion （A） were identified in OsLCT1, and one tdnucleotide （TTC） deletion was identified in SPDT. These mutants can be used in rice breeding and genetic studies, and the findings are of importance for the application of γ, ray mutagenesis to the breeding of rice and other seed crops.展开更多
Stigma exsertion in male sterile lines of hybrid rice is important for seed yield.In the present study, ZS616 [Oryza sativa subsp.Xian(indica)], a male sterile line with a stigma exsertion rate(SER) as high as 94.5%, ...Stigma exsertion in male sterile lines of hybrid rice is important for seed yield.In the present study, ZS616 [Oryza sativa subsp.Xian(indica)], a male sterile line with a stigma exsertion rate(SER) as high as 94.5%, was crossed to DS552, a japonica line with almost no exserted stigmas.F3 plants with extremely low and high SER were sequenced to identify SER-associated quantitative trait loci(QTL).A major QTL for SER, qSER-3.1, was identified along with other QTL on chromosome 3 in a 3.9 Mb region.A total of 307 nonsynonymous single-nucleotide polymorphisms(SNPs) and 27 frame-shift insertion/deletions(InDels)differentiating ZS616 and DS552 were identified in the region containing qSER-3.1.Most SNPs(294) and InDels(25) were excluded after further analysis because they were shared by ZS616 and low(<2.0%) SER accessions in the Huazhong Agricultural University(HAU) core rice collection.Association analysis using the full HAU collection identified a 17-bp InDel in OS03 G0689400 as the most likely causal genetic variant underlying qSER-3.1.ZS616-type accessions(n = 54, with the 17-bp insertion) in the HAU collection had minimum(16.5%)and mean(39.6%) SERs significantly greater than those(n = 424) without the insertion(with minimum and mean SERs of 0.2% and 20.6%, respectively).Thus, this study identified a major QTL for stigma exsertion and revealed the mutation in a candidate gene for the QTL.展开更多
Bakanae is an emerging rice disease caused by the seed-and soil-borne pathogen Fusarium fujikuroi.It is becoming a more serious threat to sustainable rice production throughout rice-growing regions.Bakanae disease inf...Bakanae is an emerging rice disease caused by the seed-and soil-borne pathogen Fusarium fujikuroi.It is becoming a more serious threat to sustainable rice production throughout rice-growing regions.Bakanae disease infection is responsible for high yield losses ranging from 3%to 95%,and disease incidence varies based on the region and cultivars.Hence,understanding the nature of the pathogen,its pathogenicity,disease epidemiology,symptoms,host–pathogen interaction,and the role of secondary metabolites in the disease cycle will be helpful in the development of effective and sustainable management strategies.However,very few comprehensive studies have described the details of rice bakanae disease.Thus,in this review we summarize and discuss in detail the information available from 1898 to 2023 on various critical facets of bakanae disease,and provide perspectives on future research.展开更多
Plant breeding is well recognized as one of the most important means to meet food security challenges caused by the ever-increasing world population. During the past three decades, plant breeding has been empowered by...Plant breeding is well recognized as one of the most important means to meet food security challenges caused by the ever-increasing world population. During the past three decades, plant breeding has been empowered by both new knowledge on trait development and regulation(e.g., functional genomics) and new technologies(e.g., biotechnologies and phenomics). Gene editing, particularly by clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas) and its variants, has become a powerful technology in plant research and may become a game-changer in plant breeding. Traits are conferred by coding and non-coding genes. From this perspective, we propose different editing strategies for these two types of genes. The activity of an encoded enzyme and its quantity are regulated at transcriptional and post-transcriptional, as well as translational and post-translational, levels. Different strategies are proposed to intervene to generate gene functional variations and consequently phenotype changes. For non-coding genes, trait modification could be achieved by regulating transcription of their own or target genes via gene editing. Also included is a scheme of protoplast editing to make gene editing more applicable in plant breeding. In summary, this review provides breeders with a host of options to translate gene biology into practical breeding strategies, i.e., to use gene editing as a mechanism to commercialize gene biology in plant breeding.展开更多
Aromatic rice belongs to a small but important sub-group of rice,which is highly regarded for its excellent aroma and superior grain quality.Aromatic rice,especially Basmati-and Jasmine-type rice,is being traded at a ...Aromatic rice belongs to a small but important sub-group of rice,which is highly regarded for its excellent aroma and superior grain quality.Aromatic rice,especially Basmati-and Jasmine-type rice,is being traded at a high price in the local and global markets.Genetically,rice aroma is a phenotypical expression of spontaneous recessive mutations of the OsBadh2 gene(also known as fgr/badh2/osbadh2/os2AP gene).These mutations inhibit the flow ofγ-aminobutyraldehyde(GAB-ald)toγ-aminobutyric acid(GABA),and consequently,the accumulated GAB-ald is diverted to a potent flavour component 2-acetyl-1-pyrroline(2AP)by a non-enzymatic reaction with methylglyoxal.The natural incidence of non-functional osbadh2 mutation along with selection and nursing by the farmer from the ancient time makes rice aroma as a prominent natural gift.As GABA and methylglyoxal play significant roles in stress tolerance,and their biosynthesis is strictly regulated in rice plants,the accumulation of 2AP in aromatic rice depends on the interaction of various genetic and environmental factors,and its production may come at some costs of sacrificing tolerance.This review focused on some potential underlying genes in the 2AP and GABA biosynthesis pathways,and analyzed most aspects of aroma formation in rice,and summarized the molecular mechanism of aroma production together with its genetic and non-genetic influencing factors.The present review also stated approaches to produce high-quality aromatic rice via developing novel cultivars and with good agronomic knowledge-based practice.展开更多
High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In th...High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In this study,we subjected rice cultivars Huanghuazhan(heat-resistant)and IR36(heat-sensitive)to high temperature(HT,40 oC)or normal temperature(NT,33 oC)for 7 d at the panicle initiation stage,in conjunction with application of 24-epibrassinolide[EBR,a synthetic brassinolide(BR)]or brassinazole(BRZ,a BR biosynthesis inhibitor)at the beginning of the treatments.HT exacerbated spikelet degeneration and inhibited young panicle growth,which were partially prevented by EBR application,while BRZ application aggravated the reduction in spikelet number.HT decreased the contents of BR,active cytokinins(aCTK),active gibberellins(aGA)and indole-3-acetic acid(IAA),but increased the content of abscisic acid(ABA)in young panicles.The activities of key enzymes involved in sucrose hydrolysis,glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT.In addition,the contents of H2O2 and malondialdehyde(MDA)were increased and the activities of antioxidant enzymes were decreased in young panicles.Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR,aCTK,aGA and ABA,thus promoting the decomposition and utilization of sucrose in young panicles,enhancing the activities of superoxide dismutase,catalase and peroxidase,and reducing the accumulation of H2O2 and MDA in young panicles,whereas application of BRZ had the opposite physiological effects.These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice.展开更多
Ten F1 combinations with their male and female parents were employed to evaluate their heat tolerance during the flowering and early grain filling stages. The rice plants were subjected to heat stress（39 °C–43 ...Ten F1 combinations with their male and female parents were employed to evaluate their heat tolerance during the flowering and early grain filling stages. The rice plants were subjected to heat stress（39 °C–43 °C） for 1–15 d during flowering. Based on the heat stress index, heat tolerance was only observed in the F1 combinations H2（K22A × R207）, H3（Bobai A × R207） and H4（Bobai A × Minghui 63）, whereas the others received above 0.5000 of heat stress index. Both parents of the tolerant combination（heat-tolerant × heat-tolerant） possessed heat tolerance, whereas the susceptible combinations were crossed by heat-tolerant（sterile lines） × heat-susceptible（restorer lines）, heat-susceptible × heat-tolerant, or heat-susceptible × heat-susceptible parents. This result indicated that heat tolerance in rice was controlled by recessive genes. Thus, both parents should possess high temperature tolerance to develop heat-tolerant F1 combinations. Furthermore, the heat stress index of F1 combinations was significantly correlated with the heat stress index of restorer lines but not with the heat stress index of maintainer lines. This result suggested that male parents play a more important role in heat-tolerant combinations than female parents. Therefore, the heat susceptibility of the hybrid rice in China is mainly due to the wide application of low-heat-tolerant restorer lines with high yield in three-line hybrid rice breeding.展开更多
A novel rice mutant lmi1 showed increased resistance to bacterial blight.LMI1 encodes a DUF292 protein and regulates defense immune responses and cell death via vesicle trafficking in chloroplasts.
Transcriptional regulation of cold-responsive genes plays crucial roles in plant cold tolerance,but the transcription factors(TFs)-centered regulatory networks remain largely unclear.In this study,we show that Monocul...Transcriptional regulation of cold-responsive genes plays crucial roles in plant cold tolerance,but the transcription factors(TFs)-centered regulatory networks remain largely unclear.In this study,we show that Monoculm1(MOC1),a critical TF controlling tiller number and plant height in rice,positively regulates rice cold tolerance at the seedling stage.We found that OsMPK4,a mitogen-activated protein kinase,phosphorylates and stabilizes MOC1 under cold stress.Further investigations revealed that MOC1 recruits the TFs OsbZIP79 and OsNAC5 to form a triple complex and subsequently enhances their stability by inhibiting proteasome-mediated degradation under cold stress.Notably,we found that the OsbZIP79-MOC1-OsNAC5 complex activates several cold-responsive genes,including Dehydration-responsive element-binding factor 1G(OsDREB1G),to confer rice cold tolerance.Haplotype analysis of the OsDREB1G promoter in>10,000 rice accessions identified the favorable haplotype and key variants that endow rice cold tolerance.Collectively,our work demonstrates a pivotal role of the OsMPK4-OsbZIP79-MOC1-OsNAC5-OsDREB1G module in regulating rice cold tolerance and provides genetic targets for improving cold tolerance through molecular breeding.展开更多
Purple rice is a type of rice with anthocyanins deposited in its grain pericarp. The rice Pb gene control-ling purple pericarp character is known to be on chromosome 4,and the purple color is dominant over white color...Purple rice is a type of rice with anthocyanins deposited in its grain pericarp. The rice Pb gene control-ling purple pericarp character is known to be on chromosome 4,and the purple color is dominant over white color. In this study,we fine mapped the Pb gene using two F2 segregating populations,i.e. Pei'ai 64S(white) × Yunanheixiannuo(purple) and Pei'ai 64S × Chuanheinuo(purple) . In the first-pass map-ping,the Pb gene was located in the region downstream the SSR marker RM3820. In the fine mapping,the candidate region was saturated with InDel and CAPS markers developed specifically for this study. Eventually,the Pb gene was mapped within the 25-kb region delimited by the upstream marker RID3 and the downstream marker RID4. The delimited region contained two annotated genes,Ra and bhlh16(TIGR Rice Genome,R.5) . The former is a homologue of the Myc transcription factor Lc controlling anthocyanin biosynthesis in maize,and the latter is a homologue of the TT8 gene,which is also an Myc transcription factor gene controlling the pericarp pigmentation in Arabidopsis thaliana. Sequence analysis showed that the exon 7 of the Ra gene of Yunanheixiannuo and Chuanheinuo had a 2-bp(GT) deletion compared with those of the white rice varieties Pei'ai 64S,9311 and Nipponbare. A CAPS marker,CAPSRa,was developed according to the GT deletion for analysis of the two F2 segregating populations and 106 rice lines. The results showed that all F2 plants with white pericarp,and all non-purple rice lines(63 white and 22 red) contained no GT deletion,but all 20 purple rice lines con-tained the GT deletion. These results suggested that the Ra gene may be the Pb gene and the purple pericarp characteristic of rice is caused by the GT deletion within exon 7 of the Ra gene.展开更多
The roles of signaling pathways in the production of trypsin proteinase inhibitors(TrypPIs)in rice infested by the leaf folder(LF) Cnaphalocrocis medinalis were studied.Infestation by LF increased TrypPI levels in the...The roles of signaling pathways in the production of trypsin proteinase inhibitors(TrypPIs)in rice infested by the leaf folder(LF) Cnaphalocrocis medinalis were studied.Infestation by LF increased TrypPI levels in the leaves of rice plants at the tillering,booting and flowering stages but decreased TrypPI levels at the ripening stage;TrypPI levels in rice stems did not increase at any developmental stage.Infestation by LF at the tillering stage systemically increased TrypPI levels in leaves but not in stems;it also enhanced salicylic acid(SA)levels in leaves and stems,and the ethylene level released from plants.However,LF infestation did not increase JA concentrations.Exogenous application of SA or ethylene enhanced TrypPI levels in the leaves and stems of plants at the tillering stage,whereas treatment with both SA and ethylene induced lower levels of TrypPIs than treatment with SA or ethylene alone,suggesting an antagonistic effect of SA and ethylene on TrypPIs induction.The results suggest that both SA and ethylene signaling pathways are involved in the production of TrypPIs in rice induced by LF;moreover,the antagonistic effect of SA and ethylene may explain the changes in TrypPI levels seen at different plant developmental stages and in different organs.展开更多
Plant seed oil is important for human dietary consumption and industrial application. The oil trait is controlled by quantitative trait loci （QTLs）, but no QTLs for fatty acid composition are known in rice, the mono...Plant seed oil is important for human dietary consumption and industrial application. The oil trait is controlled by quantitative trait loci （QTLs）, but no QTLs for fatty acid composition are known in rice, the monocot model plant. QTL analysis was performed using F2 and F2：3 progeny from a cross of an indica variety and a japonica variety. Gas chroma- tography-mass spectrometry （GC-MS） analysis revealed significant differences between parental lines in fatty acid com- position of brown rice oil, and 29 associated QTLs in F2 and/or F2：3 populations were identified throughout the rice genome, except chromosomes 9 and 10. Eight QTLs were repeatedly identified in both populations across different envi- ronments. Five loci pleiotropically controlled different traits, contributing to complex interactions of oil with fatty acids and between fatty acids. Nine rice orthologs of Arabidopsis genes encoding key enzymes in lipid metabolism co-localized with 11 mapped QTLs. A strong QTL for oleic （18：1） and linoleic （18：2） acid were associated with a rice ortholog of a gene encoding acyI-CoA：diacylglycerol acyltransferase （DGAT）, and another for palmitic acid （16：0） mapped similarly to the acyl- ACP thioesterase （FatB） gene ortholog. Our approach rapidly and efficiently identified candidate genes for mapped QTLs controlling fatty acid composition and oil concentration, providing information for improving rice grain quality by marker assisted selection.展开更多
MicroRNAs(miRNAs)have started to play an important role in pest control,and novel miRNA-based transgenic insect-resistant plants are now emerging.However,an environmental risk assessment of these novel transgenic plan...MicroRNAs(miRNAs)have started to play an important role in pest control,and novel miRNA-based transgenic insect-resistant plants are now emerging.However,an environmental risk assessment of these novel transgenic plants expressing insect miRNAs must be undertaken before promoting their application.Here,transgenic miR-14 rice,which has high resistance to the rice stem borer Chilo suppressalis,was used as an example for evaluation in this study.Taking the tier 1 risk assessment method in Bacillus thuringiensis(Bt)crops as a reference,the effects of the direct exposure of a non-target parasitoid,Cotesia chilonis,to a high concentration of miRNA were evaluated.The results showed that direct feeding with miR-14 at high concentration had no significant effects on the biological parameters of Co.chilonis,whereas when miR-14 was injected into Ch.suppressalis-parasitized larvae,the development duration of Co.chilonis was significantly affected.In combination with the real conditions of the rice paddy field,it could be inferred that transgenic miR-14 rice has no significant negative effects on the important non-target parasitoid,Co.chilonis.These results will provide a foundation for the establishment of a new safety evaluation system for novel RNAi-based transgenic plants.展开更多
Serotonin(5-hydroxytryptamine(5-HT))is a pineal hormone and a secondary metabolite related to various hormonal and physiological functions at the organ,tissue,and cellular levels.It is considered increasingly importan...Serotonin(5-hydroxytryptamine(5-HT))is a pineal hormone and a secondary metabolite related to various hormonal and physiological functions at the organ,tissue,and cellular levels.It is considered increasingly important in regulating animal behavior,but the function of serotonin in plants is far less known.According to recent research,serotonin is vital for plant growth,development,and stress responses,achieved through transcriptional and phytohormonal interplay.Specifically,this review addresses critical gaps in the understanding of serotonin's function in plants by examining its biosynthesis,metabolism,and its multifaceted role in mitigating both abiotic stresses(salinity,drought,heat,cold,and heavy metals)as well as biotic challenges(pathogens,pests,and herbivores).As a pivotal player,it engages in a variety of significant cellular and molecular interactions,including those with reactive oxygen and nitrogen species(RONS),and various phytohormones such as auxin,abscisic acid(ABA),salicylic acid(SA),jasmonic acid(JA),ethylene(ET),and cytokinin(CK).Advances in serotonin-related research are anticipated to offer a valuable basis for uncovering the regulatory pathways by which serotonin impacts the resilience of crops against abiotic stress.展开更多
Due to its tropical origins,rice(Oryza sativa)is susceptible to cold stress,which poses severe threats to production.OsNAC5,a NAC-type transcription factor,participates in the cold stress response of rice,but the deta...Due to its tropical origins,rice(Oryza sativa)is susceptible to cold stress,which poses severe threats to production.OsNAC5,a NAC-type transcription factor,participates in the cold stress response of rice,but the detailed mechanisms remain poorly understood.Here,we demonstrate that OsNAC5 positively regulates cold tolerance at germination and in seedlings by directly activating the expression of ABSCISIC ACID INSENSITIVE 5(OsABI5).Haplotype analysis indicated that single nucleotide polymorphisms in a NAC-binding site in the OsABI5 promoter are strongly associated with cold tolerance.OsNAC5 also enhanced OsABI5 stability,thus regulating the expression of cold-responsive(COR)genes,enabling fine-tuned control of OsABI5 action for rapid,precise plant responses to cold stress.DNA affinity purification sequencing coupled with transcriptome deep sequencing identified several OsABI5 target genes involved in COR expression,including DEHYDRATION-RESPONSIVE ELEMENT BINDING FACTOR 1A(OsDREB1A),OsMYB20,and PEROXIDASE 70(OsPRX70).In vivo and in vitro analyses suggested that OsABI5 positively regulates COR gene transcription,with marked COR upregulation in OsNAC5-overexpressing lines and downregulation in osnac5 and/or osabi5 knockout mutants.This study extends our understanding of cold tolerance regulation via OsNAC5 through the OsABI5-CORs transcription module,which may be used to ameliorate cold tolerance in rice via advanced breeding.展开更多
基金supported by the Zhejiang Provincial S & T Project on Breeding of Agricultural (Food) Crops (Grant No. 2016C02050-2)
文摘To explore how rice(Oryza sativa L.) can be safely produced in Cd-polluted soil, OsLCT1 and OsNramp5 mutant lines were generated by CRISPR/Cas9-mediated mutagenesis. One of OsLCT1 mutant(lct1×1) and two of OsNramp5 mutants(nramp5×7 and nramp5×9) were evaluated for grain Cd accumulation and agronomic performances. In paddy field soil containing approximately 0.9 mg/kg Cd, lct1×1 grains contained approximately 40%(0.17 mg/kg) of the Cd concentration of the wild type parental line, less than the China National Food Safety Standard(0.20 mg/kg). Both OsNramp5 mutants showed low grain Cd accumulation(< 0.06 mg/kg) in the paddy(approximately 0.9 mg/kg Cd) or in pots in soil spiked with 2 mg/kg Cd. However, only nramp5×7 showed normal growth and yield, whereas the growth of nramp5×9 was severely impaired. The study showed that lct1×1 could be used to produce rice grains safe for human consumption in lightly contaminated paddy soils and nramp5×7 used in soils contaminated by much higher levels of Cd.
基金This study was supported by the Zhejiang Provincial Natural Science Foundation,China(Grant Nos.LY19C130006 and LY20C130011)the Open Project Program of State Key Laboratory of Rice Biology,China(Grant No.20190403)+1 种基金the National Rice Industry Technology System,China(Grant No.CARS-01)and the Central Public Interest Research Institute Special Fund in China(Grant No.2017RG004-1).
文摘Nitrogen(N),phosphorus(P)and potassium(K)are important essential nutrients for plant growth and development,but their functions in energy status remains unclear.Here,we grew Nipponbare rice seedlings in a growth chamber for 20 d at 30℃/24℃day/night)under natural sunlight conditions with different nutrient regimes.The results showed that N had the strongest influence on the plant growth and development,followed by P and K.The highest nonstructural carbohydrate content,dry matter weight,net photosynthetic rate(Pn),ATP content,as well as NADH dehydrogenase,cytochrome oxidase and ATPase activities were found in the plants that received sufficient N,P and K.The lowest values of these parameters were detected in the N-deficient plants.Higher dry matter accumulation was observed in the K-deficient than in the P-deficient treatments,but there was no significant difference in the ratio of respiration rate to Pn between these two treatments,suggesting that differences in energy production efficiency may have accounted for this result.This hypothesis was confirmed by higher ATP contents and activities of NADH dehydrogenase,cytochrome oxidase and ATPase in the K-deficient plants than in the P-deficient plants.We therefore inferred different abilities in energy production efficiency among N,P and K in rice seedlings,which determined rice plant growth and development.
基金supported by the National Natural Science Foundation of China(Grant Nos.30871473 and 31101116)the Project from the China National Rice Research Institute(Grant No.2009RG003-5)+1 种基金the Projects from local government of Zhejiang Province, China(Grant Nos.2008C22073,2009C32048 and SN200806)the Zhejiang Provincial Natural Science Foundation,China(Grant Nos.Y3100060 and Y3100090)
文摘Fifteen common rice maintainer lines and 26 high-yielding restorer lines were used to evaluate their thermal resistance and fertility during flowering and early grain filling stages. The rice plants were subjected to high temperature stress （39-43 ℃） for 1-15 d from main stem flowering. Based on the heat stress index, they were divided into thermal resistant lines, semi-thermal resistant lines, semi-thermal sensitive lines and thermal sensitive lines. Therefore, the maintainer lines K22B, Bobai B and V20B belonged to thermal resistant lines, whereas 11-32B, Zhongzhe B and Zhong 9B belonged to thermal sensitive lines. For rice restorer lines, Minghui 63 had the highest thermal resistance, followed by R207, P32, P929, and the lowest thermal resistant lines P62-2-2, R8006 and P51. The correlation analysis indicated that the heat stress index was significantly correlated with seed-setting rate and abortive grain rate under heat stress, but not under natural conditions. This indicated that heat stress occurred during flowering and early grain filling stages mainly decreased the seed- setting rate and significantly increased the abortive grain rate in both rice maintainer and restorer lines.
基金supported by grants from the Ministry of Agriculture of China(2009ZX08009-102B)Chinese Academy of Sciences(KSCX3-EW-N-01)+2 种基金the Ministry of Science and Technology of China(2012CB944800)the National Natural Science Foundation of China(31130071)the Zhejiang Provincial Natural Science Foundation of China (Y3110394)
文摘Rice grain shape, grain length （GL）, width （GW）, thickness （GT） and length-to-width ratio （LWR）, are usually controlled by multiple quantitative trait locus （QTL）. To elucidate the genetic basis of extremely large grain shape, QTL analysis was performed using an F2 population derived from a cross between a japonica cuttivar ＇JZI560＇ （extremely large grain） and a contrasting indica cultivar ＇FAZI＇ （small grain）. A total number of 24 QTLs were detected on seven different chromosomes. QTLs for GL, GW, GT and LWR explained 11.6%, 95.62%, 91.5% and 89.9% of total phenotypic variation, respectively. Many QTLs pleiotropically controlled different grain traits, contributing complex traits correlation. GW2 and qSW5/GW5, which have been cloned previously to control GW, showed similar chromosomal locations with qGW2-1/qGT2-1/qLWR2-2 and qGW5-2/qLWR5-1 and should be the right candidate genes. Plants pyramiding GW2 and qSW5/GW5 showed a significant increase in GW compared with those carrying one of the two major QTLs. Furthermore, no significant QTL interaction was observed between GW2 and qSW5/GW5. These results suggested that GW2 and qSW5/GW5 might work in independent pathways to regulate grain traits. ＇JZ1560＇ alleles underlying all QTLs contributed an increase in GW and GT and the accumulation of additive effects generates the extremely large grain shape in ＇JZ1560＇.
基金supported by the National Natural Science Foundation of China(No.11275171)the National Key Technology R&D Program of China(No.2014BAA03B04)the Mutation Breeding Project of the Forum for Nuclear Cooperation in Asia(FNCA)
文摘Mutation breeding is based on the induction of genetic variations; hence knowledge of the frequency and type of induced mutations is of paramount importance for the design and implementation of a mutation breeding program. Although γ ray irradiation has been widely used since the 1960 s in the breeding of about 200 economically important plant species, molecular elucidation of its genetic effects has so far been achieved largely by analysis of target genes or genomic regions. In the present study, the whole genomes of six γ-irradiated M2 rice plants were sequenced; a total of 144–188 million high-quality（Q〉20） reads were generated for each M2 plant, resulting in genome coverage of 45 times for each plant. Single base substitution（SBS） and short insertion/deletion（Indel） mutations were detected at the average frequency of 7.5×10^-6～9.8×10^-6 in the six M2 rice plants（SBS being about 4 times more frequent than Indels）. Structural and copy number variations, though less frequent than SBS and Indel, were also identified and validated. The mutations were scattered in all genomic regions across 12 rice chromosomes without apparent hotspots. The present study is the first genome-wide single-nucleotide resolution study on the feature and frequency of γ irradiation-induced mutations in a seed propagated crop; the findings are of practical importance for mutation breeding of rice and other crop species.
基金Project supported by the National Key Research and Development Program of China(No.2016YFD0102103)
文摘Targeting Induced Local Lesions IN Genomes （TILLING） is a reverse genetics strategy for the high-throughput screening of induced mutations.γ, radiation, which often induces both insertion/deletion （Indel） and point mutations, has been widely used in mutation induction and crop breeding. The present study aimed to develop a simple, high-throughput TILLING system for screening γ ray-induced mutations using high-resolution melting （HRM） analysis. Pooled rice （Oryza sativa） samples mixed at a 1：7 ratio of Indel mutant to wild-type DNA could be distinguished from the wild-type controls by HRM analysis. Thus, an HRM-TILLING system that analyzes pooled samples of four M2 plants is recommended for screening γ, ray-induced mutants in rice. For demonstration, a γ, ray-mutagenized M2 rice population （n=4560） was screened for mutations in two genes, OsLCT1 and SPDT, using this HRM-TILLING system. Mutations including one single nucleotide substitution （G→A） and one single nucleotide insertion （A） were identified in OsLCT1, and one tdnucleotide （TTC） deletion was identified in SPDT. These mutants can be used in rice breeding and genetic studies, and the findings are of importance for the application of γ, ray mutagenesis to the breeding of rice and other seed crops.
基金supported by the Zhejiang Provincial S&T Project on Breeding of Agricultural (Food) Crops (2016C020502)the Major Science and Technology Innovation Program of Hangzhou, China (2015012A09)
文摘Stigma exsertion in male sterile lines of hybrid rice is important for seed yield.In the present study, ZS616 [Oryza sativa subsp.Xian(indica)], a male sterile line with a stigma exsertion rate(SER) as high as 94.5%, was crossed to DS552, a japonica line with almost no exserted stigmas.F3 plants with extremely low and high SER were sequenced to identify SER-associated quantitative trait loci(QTL).A major QTL for SER, qSER-3.1, was identified along with other QTL on chromosome 3 in a 3.9 Mb region.A total of 307 nonsynonymous single-nucleotide polymorphisms(SNPs) and 27 frame-shift insertion/deletions(InDels)differentiating ZS616 and DS552 were identified in the region containing qSER-3.1.Most SNPs(294) and InDels(25) were excluded after further analysis because they were shared by ZS616 and low(<2.0%) SER accessions in the Huazhong Agricultural University(HAU) core rice collection.Association analysis using the full HAU collection identified a 17-bp InDel in OS03 G0689400 as the most likely causal genetic variant underlying qSER-3.1.ZS616-type accessions(n = 54, with the 17-bp insertion) in the HAU collection had minimum(16.5%)and mean(39.6%) SERs significantly greater than those(n = 424) without the insertion(with minimum and mean SERs of 0.2% and 20.6%, respectively).Thus, this study identified a major QTL for stigma exsertion and revealed the mutation in a candidate gene for the QTL.
基金supported by the National Nuclear Energy Exploitation Program-Nuclear Irradiation for Crop Improvement and Insect Eradication and the International Atomic Energy Agency(IAEA)Coordination Research Project(No.D23020-23042),China.
文摘Bakanae is an emerging rice disease caused by the seed-and soil-borne pathogen Fusarium fujikuroi.It is becoming a more serious threat to sustainable rice production throughout rice-growing regions.Bakanae disease infection is responsible for high yield losses ranging from 3%to 95%,and disease incidence varies based on the region and cultivars.Hence,understanding the nature of the pathogen,its pathogenicity,disease epidemiology,symptoms,host–pathogen interaction,and the role of secondary metabolites in the disease cycle will be helpful in the development of effective and sustainable management strategies.However,very few comprehensive studies have described the details of rice bakanae disease.Thus,in this review we summarize and discuss in detail the information available from 1898 to 2023 on various critical facets of bakanae disease,and provide perspectives on future research.
基金Project supported by the Zhejiang Provincial S&T Project on Breeding Agricultural(Food)Crops(No.2016C02050-2)the National Natural Science Foundation of China(No.31701394)。
文摘Plant breeding is well recognized as one of the most important means to meet food security challenges caused by the ever-increasing world population. During the past three decades, plant breeding has been empowered by both new knowledge on trait development and regulation(e.g., functional genomics) and new technologies(e.g., biotechnologies and phenomics). Gene editing, particularly by clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas) and its variants, has become a powerful technology in plant research and may become a game-changer in plant breeding. Traits are conferred by coding and non-coding genes. From this perspective, we propose different editing strategies for these two types of genes. The activity of an encoded enzyme and its quantity are regulated at transcriptional and post-transcriptional, as well as translational and post-translational, levels. Different strategies are proposed to intervene to generate gene functional variations and consequently phenotype changes. For non-coding genes, trait modification could be achieved by regulating transcription of their own or target genes via gene editing. Also included is a scheme of protoplast editing to make gene editing more applicable in plant breeding. In summary, this review provides breeders with a host of options to translate gene biology into practical breeding strategies, i.e., to use gene editing as a mechanism to commercialize gene biology in plant breeding.
基金the Institute of Crop Science, College of Agriculture and Biotechnology, Zhejiang University, China for providing postdoctoral fellowship, facilities and supports during this research.
文摘Aromatic rice belongs to a small but important sub-group of rice,which is highly regarded for its excellent aroma and superior grain quality.Aromatic rice,especially Basmati-and Jasmine-type rice,is being traded at a high price in the local and global markets.Genetically,rice aroma is a phenotypical expression of spontaneous recessive mutations of the OsBadh2 gene(also known as fgr/badh2/osbadh2/os2AP gene).These mutations inhibit the flow ofγ-aminobutyraldehyde(GAB-ald)toγ-aminobutyric acid(GABA),and consequently,the accumulated GAB-ald is diverted to a potent flavour component 2-acetyl-1-pyrroline(2AP)by a non-enzymatic reaction with methylglyoxal.The natural incidence of non-functional osbadh2 mutation along with selection and nursing by the farmer from the ancient time makes rice aroma as a prominent natural gift.As GABA and methylglyoxal play significant roles in stress tolerance,and their biosynthesis is strictly regulated in rice plants,the accumulation of 2AP in aromatic rice depends on the interaction of various genetic and environmental factors,and its production may come at some costs of sacrificing tolerance.This review focused on some potential underlying genes in the 2AP and GABA biosynthesis pathways,and analyzed most aspects of aroma formation in rice,and summarized the molecular mechanism of aroma production together with its genetic and non-genetic influencing factors.The present review also stated approaches to produce high-quality aromatic rice via developing novel cultivars and with good agronomic knowledge-based practice.
基金funded by the Natural Science Foundation of Zhejiang Province,China(Grant No.LQ20C130009)the Science and Technology Project of Zhejiang Province,China(Grant No.2022C02034)the Special Fund for China Agricultural Research System(Grant No.CARS-01-22)。
文摘High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice(Oryza sativa L.).Brassinosteroids play important roles in enhancing crop stress resistance.In this study,we subjected rice cultivars Huanghuazhan(heat-resistant)and IR36(heat-sensitive)to high temperature(HT,40 oC)or normal temperature(NT,33 oC)for 7 d at the panicle initiation stage,in conjunction with application of 24-epibrassinolide[EBR,a synthetic brassinolide(BR)]or brassinazole(BRZ,a BR biosynthesis inhibitor)at the beginning of the treatments.HT exacerbated spikelet degeneration and inhibited young panicle growth,which were partially prevented by EBR application,while BRZ application aggravated the reduction in spikelet number.HT decreased the contents of BR,active cytokinins(aCTK),active gibberellins(aGA)and indole-3-acetic acid(IAA),but increased the content of abscisic acid(ABA)in young panicles.The activities of key enzymes involved in sucrose hydrolysis,glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT.In addition,the contents of H2O2 and malondialdehyde(MDA)were increased and the activities of antioxidant enzymes were decreased in young panicles.Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR,aCTK,aGA and ABA,thus promoting the decomposition and utilization of sucrose in young panicles,enhancing the activities of superoxide dismutase,catalase and peroxidase,and reducing the accumulation of H2O2 and MDA in young panicles,whereas application of BRZ had the opposite physiological effects.These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice.
基金funded by the National Natural Science Foundation of China (Grant Nos. 31201150 and 31101116)the Research Grant of China National Rice Research Institute (Grant No. 2012RG004-3)+1 种基金the Special Fund for Agro-Scientific Research in the Public Interest (Grant No. 201203029)the National System of Rice Industry (Grant No. CARS-01-27)
文摘Ten F1 combinations with their male and female parents were employed to evaluate their heat tolerance during the flowering and early grain filling stages. The rice plants were subjected to heat stress（39 °C–43 °C） for 1–15 d during flowering. Based on the heat stress index, heat tolerance was only observed in the F1 combinations H2（K22A × R207）, H3（Bobai A × R207） and H4（Bobai A × Minghui 63）, whereas the others received above 0.5000 of heat stress index. Both parents of the tolerant combination（heat-tolerant × heat-tolerant） possessed heat tolerance, whereas the susceptible combinations were crossed by heat-tolerant（sterile lines） × heat-susceptible（restorer lines）, heat-susceptible × heat-tolerant, or heat-susceptible × heat-susceptible parents. This result indicated that heat tolerance in rice was controlled by recessive genes. Thus, both parents should possess high temperature tolerance to develop heat-tolerant F1 combinations. Furthermore, the heat stress index of F1 combinations was significantly correlated with the heat stress index of restorer lines but not with the heat stress index of maintainer lines. This result suggested that male parents play a more important role in heat-tolerant combinations than female parents. Therefore, the heat susceptibility of the hybrid rice in China is mainly due to the wide application of low-heat-tolerant restorer lines with high yield in three-line hybrid rice breeding.
基金supported in part by the Natural Science Foundation of Zhejiang Province (LZ23C130003)Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-CSCB-202402)National Key Research and Development Program of China (2021YFA1300703).
文摘A novel rice mutant lmi1 showed increased resistance to bacterial blight.LMI1 encodes a DUF292 protein and regulates defense immune responses and cell death via vesicle trafficking in chloroplasts.
基金supported by the National Natural Science Foundation of China(32570362,32460077,and 32570749)the Hainan Province Science and Technology Special Fund(ZDYF2025XDNY093)+4 种基金the Hainan Provincial Natural Science Foundation of China(325RC799)the Nanhai New Star Technology Innovation Talent Platform Project of Hainan Province(NHXXRCXM202362)the Research Startup Funding from Hainan Institute of Zhejiang University(0201-6602-A12203)the Open Project Program of the State Key Laboratory of Rice Biology and Breeding(20240101)the Open Project Program of Jiaxing Academy of Agricultural Sciences(202405).
文摘Transcriptional regulation of cold-responsive genes plays crucial roles in plant cold tolerance,but the transcription factors(TFs)-centered regulatory networks remain largely unclear.In this study,we show that Monoculm1(MOC1),a critical TF controlling tiller number and plant height in rice,positively regulates rice cold tolerance at the seedling stage.We found that OsMPK4,a mitogen-activated protein kinase,phosphorylates and stabilizes MOC1 under cold stress.Further investigations revealed that MOC1 recruits the TFs OsbZIP79 and OsNAC5 to form a triple complex and subsequently enhances their stability by inhibiting proteasome-mediated degradation under cold stress.Notably,we found that the OsbZIP79-MOC1-OsNAC5 complex activates several cold-responsive genes,including Dehydration-responsive element-binding factor 1G(OsDREB1G),to confer rice cold tolerance.Haplotype analysis of the OsDREB1G promoter in>10,000 rice accessions identified the favorable haplotype and key variants that endow rice cold tolerance.Collectively,our work demonstrates a pivotal role of the OsMPK4-OsbZIP79-MOC1-OsNAC5-OsDREB1G module in regulating rice cold tolerance and provides genetic targets for improving cold tolerance through molecular breeding.
文摘Purple rice is a type of rice with anthocyanins deposited in its grain pericarp. The rice Pb gene control-ling purple pericarp character is known to be on chromosome 4,and the purple color is dominant over white color. In this study,we fine mapped the Pb gene using two F2 segregating populations,i.e. Pei'ai 64S(white) × Yunanheixiannuo(purple) and Pei'ai 64S × Chuanheinuo(purple) . In the first-pass map-ping,the Pb gene was located in the region downstream the SSR marker RM3820. In the fine mapping,the candidate region was saturated with InDel and CAPS markers developed specifically for this study. Eventually,the Pb gene was mapped within the 25-kb region delimited by the upstream marker RID3 and the downstream marker RID4. The delimited region contained two annotated genes,Ra and bhlh16(TIGR Rice Genome,R.5) . The former is a homologue of the Myc transcription factor Lc controlling anthocyanin biosynthesis in maize,and the latter is a homologue of the TT8 gene,which is also an Myc transcription factor gene controlling the pericarp pigmentation in Arabidopsis thaliana. Sequence analysis showed that the exon 7 of the Ra gene of Yunanheixiannuo and Chuanheinuo had a 2-bp(GT) deletion compared with those of the white rice varieties Pei'ai 64S,9311 and Nipponbare. A CAPS marker,CAPSRa,was developed according to the GT deletion for analysis of the two F2 segregating populations and 106 rice lines. The results showed that all F2 plants with white pericarp,and all non-purple rice lines(63 white and 22 red) contained no GT deletion,but all 20 purple rice lines con-tained the GT deletion. These results suggested that the Ra gene may be the Pb gene and the purple pericarp characteristic of rice is caused by the GT deletion within exon 7 of the Ra gene.
基金supported by the National Basic Research Program of China(2010CB126200)the Innovation Research Team Program of the National Natural Science Foundation of China(31021003)the earmarked fund for Modern Agro-industry Technology Research System
文摘The roles of signaling pathways in the production of trypsin proteinase inhibitors(TrypPIs)in rice infested by the leaf folder(LF) Cnaphalocrocis medinalis were studied.Infestation by LF increased TrypPI levels in the leaves of rice plants at the tillering,booting and flowering stages but decreased TrypPI levels at the ripening stage;TrypPI levels in rice stems did not increase at any developmental stage.Infestation by LF at the tillering stage systemically increased TrypPI levels in leaves but not in stems;it also enhanced salicylic acid(SA)levels in leaves and stems,and the ethylene level released from plants.However,LF infestation did not increase JA concentrations.Exogenous application of SA or ethylene enhanced TrypPI levels in the leaves and stems of plants at the tillering stage,whereas treatment with both SA and ethylene induced lower levels of TrypPIs than treatment with SA or ethylene alone,suggesting an antagonistic effect of SA and ethylene on TrypPIs induction.The results suggest that both SA and ethylene signaling pathways are involved in the production of TrypPIs in rice induced by LF;moreover,the antagonistic effect of SA and ethylene may explain the changes in TrypPI levels seen at different plant developmental stages and in different organs.
基金This work was supported by grants from the Ministry of Agriculture of China （2009ZX08009--067B, 2009ZX08009-102B, 2009ZX08001- 022B）, the National Natural Science Foundation of China （30730058）, and the Shanghai Science and Technology Development （09DJ 1400503）.
文摘Plant seed oil is important for human dietary consumption and industrial application. The oil trait is controlled by quantitative trait loci （QTLs）, but no QTLs for fatty acid composition are known in rice, the monocot model plant. QTL analysis was performed using F2 and F2：3 progeny from a cross of an indica variety and a japonica variety. Gas chroma- tography-mass spectrometry （GC-MS） analysis revealed significant differences between parental lines in fatty acid com- position of brown rice oil, and 29 associated QTLs in F2 and/or F2：3 populations were identified throughout the rice genome, except chromosomes 9 and 10. Eight QTLs were repeatedly identified in both populations across different envi- ronments. Five loci pleiotropically controlled different traits, contributing to complex interactions of oil with fatty acids and between fatty acids. Nine rice orthologs of Arabidopsis genes encoding key enzymes in lipid metabolism co-localized with 11 mapped QTLs. A strong QTL for oleic （18：1） and linoleic （18：2） acid were associated with a rice ortholog of a gene encoding acyI-CoA：diacylglycerol acyltransferase （DGAT）, and another for palmitic acid （16：0） mapped similarly to the acyl- ACP thioesterase （FatB） gene ortholog. Our approach rapidly and efficiently identified candidate genes for mapped QTLs controlling fatty acid composition and oil concentration, providing information for improving rice grain quality by marker assisted selection.
基金funded by Science and Technology Innovation 2030-"Agricultural Biological Breeding"Major Project(2023ZD04062)the Experimental Technology Research Program of Zhejiang University(SYB202126).
文摘MicroRNAs(miRNAs)have started to play an important role in pest control,and novel miRNA-based transgenic insect-resistant plants are now emerging.However,an environmental risk assessment of these novel transgenic plants expressing insect miRNAs must be undertaken before promoting their application.Here,transgenic miR-14 rice,which has high resistance to the rice stem borer Chilo suppressalis,was used as an example for evaluation in this study.Taking the tier 1 risk assessment method in Bacillus thuringiensis(Bt)crops as a reference,the effects of the direct exposure of a non-target parasitoid,Cotesia chilonis,to a high concentration of miRNA were evaluated.The results showed that direct feeding with miR-14 at high concentration had no significant effects on the biological parameters of Co.chilonis,whereas when miR-14 was injected into Ch.suppressalis-parasitized larvae,the development duration of Co.chilonis was significantly affected.In combination with the real conditions of the rice paddy field,it could be inferred that transgenic miR-14 rice has no significant negative effects on the important non-target parasitoid,Co.chilonis.These results will provide a foundation for the establishment of a new safety evaluation system for novel RNAi-based transgenic plants.
基金supported by the National Science Foundation of China(32460077)the“Nanhai New Star”Technology Innovation Talent Platform Project of Hainan Province(NHXXRCXM202362)+1 种基金the Scientific Research Fund of Zhejiang Provincial Education Department(Y202353681)the Initial Scientific Research Fund of Hainan Institute,Zhejiang University(0201-6602-A12203).
文摘Serotonin(5-hydroxytryptamine(5-HT))is a pineal hormone and a secondary metabolite related to various hormonal and physiological functions at the organ,tissue,and cellular levels.It is considered increasingly important in regulating animal behavior,but the function of serotonin in plants is far less known.According to recent research,serotonin is vital for plant growth,development,and stress responses,achieved through transcriptional and phytohormonal interplay.Specifically,this review addresses critical gaps in the understanding of serotonin's function in plants by examining its biosynthesis,metabolism,and its multifaceted role in mitigating both abiotic stresses(salinity,drought,heat,cold,and heavy metals)as well as biotic challenges(pathogens,pests,and herbivores).As a pivotal player,it engages in a variety of significant cellular and molecular interactions,including those with reactive oxygen and nitrogen species(RONS),and various phytohormones such as auxin,abscisic acid(ABA),salicylic acid(SA),jasmonic acid(JA),ethylene(ET),and cytokinin(CK).Advances in serotonin-related research are anticipated to offer a valuable basis for uncovering the regulatory pathways by which serotonin impacts the resilience of crops against abiotic stress.
基金supported by the National Natural Science Foundation of China(32071946 and 32201895)the Research Startup Funding from Hainan Institute of Zhejiang University(0201-6602-A12203)+3 种基金the“Nanhai New Star”Technology Innovation Talent Platform Project of Hainan Province(NHXXRCXM202362)the PhD Scientific Research and Innovation Foundation of Sanya Yazhou Bay Science and Technology City(HSPHDSRF-2023-04-018)the Fundamental Research Funds for the Central Universities(226-2022-00012)the Agriculture Research System of Shanghai,China(202203)。
文摘Due to its tropical origins,rice(Oryza sativa)is susceptible to cold stress,which poses severe threats to production.OsNAC5,a NAC-type transcription factor,participates in the cold stress response of rice,but the detailed mechanisms remain poorly understood.Here,we demonstrate that OsNAC5 positively regulates cold tolerance at germination and in seedlings by directly activating the expression of ABSCISIC ACID INSENSITIVE 5(OsABI5).Haplotype analysis indicated that single nucleotide polymorphisms in a NAC-binding site in the OsABI5 promoter are strongly associated with cold tolerance.OsNAC5 also enhanced OsABI5 stability,thus regulating the expression of cold-responsive(COR)genes,enabling fine-tuned control of OsABI5 action for rapid,precise plant responses to cold stress.DNA affinity purification sequencing coupled with transcriptome deep sequencing identified several OsABI5 target genes involved in COR expression,including DEHYDRATION-RESPONSIVE ELEMENT BINDING FACTOR 1A(OsDREB1A),OsMYB20,and PEROXIDASE 70(OsPRX70).In vivo and in vitro analyses suggested that OsABI5 positively regulates COR gene transcription,with marked COR upregulation in OsNAC5-overexpressing lines and downregulation in osnac5 and/or osabi5 knockout mutants.This study extends our understanding of cold tolerance regulation via OsNAC5 through the OsABI5-CORs transcription module,which may be used to ameliorate cold tolerance in rice via advanced breeding.
