As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a ...As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice.展开更多
The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to signific...The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to significant yield loss caused by several biotic and abiotic factors.Among these factors,one of the most important is the high weed pressure that ravages the upland rice ecology.In Nigeria,several independent weed control techniques,such as physical,chemical and cultural methods,have been recommended and adopted for weed control across varying rice upland ecologies.However,outcomes of these approaches when used independently have not consistently led to an increase in yield.There remains an outstanding deficit between the actual yield and the potential rice yield.This review aimed to identify potential research gaps,and quest effective and sustainable weed management strategies in smallholder upland rice farming systems in Nigeria.A critical analysis of studies suggests the potential of sustainable weed management practices if adopted and adapted smartly in different upland ecologies in Nigeria.Competitiveness of upland rice against weeds can be enhanced through strategic integration of weed competitive cultivars,optimum nitrogen application timings(within weed-free periods),uniform plant spacing,and high seeding rates,with conventional herbicide/manual weed control practices.However,such management practices can only be engaged where inputs are supplied on time and the technical know-how is extended to farmers.The review equally highlights potential research gaps for further studies.展开更多
SCOPE Rice Science is an international peer-reviewed journal sponsored by China National Rice Research Institute and hosting by Elsevier B V It publishes original research papers,review articles,short communications a...SCOPE Rice Science is an international peer-reviewed journal sponsored by China National Rice Research Institute and hosting by Elsevier B V It publishes original research papers,review articles,short communications as well as letters on rice science in English language.Some of the topics that may be included in each issue are:breeding and genetics,biotechnology,germplasm resources,agronomy,pest management,soil and fertilizer management and cereal chemistry.The full texts of Rice Science are available online at http://www.ricescience.org or http://www.sciencedirect.com/joumal/rice-science.展开更多
Rice germplasm A total of 208 indica P/TGMS lines were selected for analysis from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 2), and 100 typical indica and 100 japonica accessions to ...Rice germplasm A total of 208 indica P/TGMS lines were selected for analysis from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 2), and 100 typical indica and 100 japonica accessions to identify the indica/japonica component of them were also from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 5).展开更多
To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were meas...To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains（PCG）, brown rice yield（BRY）, milled rice yield（MRY）, degree of milling（DM）, amylose content（AC）, protein content（PC）, and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size（grain length ≤ 5.5 mm） and bold shape（grain length to width ratio = 1.10-2.00）. Most of rice mutants（87.5%） had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.展开更多
Nine CBF/DREB1 homologous genes in rice were obtained by BLAST search in the NCBI database, which share conserved amino acid sequences with DREB1 protein in Arabidopsis. Three CBF genes organized in tandem, named OsCB...Nine CBF/DREB1 homologous genes in rice were obtained by BLAST search in the NCBI database, which share conserved amino acid sequences with DREB1 protein in Arabidopsis. Three CBF genes organized in tandem, named OsCBF1, OsCBF2 and OsCBF3, showed a transient induction in the process of cold acclimation, much stronger in indica rice 93-11 compared with japonica rice Nipponbare. The candidate downstream genes OsLIP5 and OsLIP9 were induced in 93-11 but not in Nipponbare. The differential expression of CBF regulon might be caused by polymorphisms within promoter sequences between these two rice varieties. These results could be useful for utilization of CBF/DREB1 genes and illustration of differences in chilling tolerance between indica and japonica rice varieties.展开更多
The newly-hatched nymphs of the small brown planthopper (SBPH), Laodelphax striatellus, including field and sensitive populations, were subjected to the high-temperature (35°C) treatment. The number of yeast-like...The newly-hatched nymphs of the small brown planthopper (SBPH), Laodelphax striatellus, including field and sensitive populations, were subjected to the high-temperature (35°C) treatment. The number of yeast-like endosymbiotes in SBPH reduced by 23.47%–34.23%, 57.86%–61.51% and 88.96%–90.71% after the high-temperature treatment for 1 d, 2 d, and 3 d, respectively. However, the size of yeast-like endosymbiotes was not obviously affected. Resistance of SBPH to three insecticides (imidacloprid, chlorpyrifos and fipronil) decreased with the increase of treatment time.展开更多
The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat （ISSR） markers. A total of 168 bands were ampl...The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat （ISSR） markers. A total of 168 bands were amplified, of which 135 polymorphic bands were discovered and the percentage of polymorphic bands （PPB） was 80.36%. A genetic diversity was revealed as Nei＇s gene diversity （H） = 0.2666 and Shannon information index （I） = 0.4028 at population level. The 34 populations were divided into different groups based on administrative regions, latitude and longitudes, river areas, altitudes of their origins, and their indexes such as Na （number of alleles）, Ne （effective number of alleles）, H, I and PPB were calculated. Richer genetic diversity was found in the wild rice populations distributed in Simao Prefecture than that in Lingcang Prefecture or Xishuangbanna Prefecture whereas the least genetic diversity was in Baoshan Prefecture or Dehong Prefecture. Rich genetic diversity was also discovered in the wild rice populations originated from higher than 710 m altitude around the middle and lower reaches of the Lancang River belonging to the Pacific Ocean drainage system. The 34 populations could be classified into two groups, one group covered the wild rice distributing in Simao Prefecture only while the other group covered ones in Lingcang, Xishuangbanna and Dehong Prefectures. The issue on how to effectively conserve the wild rice germplasm was discussed.展开更多
The allelic variation of the Wx gene in 50 non-glutinous rice varieties （lines） was analyzed by using the microsatellite marker RM190 [for （CT）n simple sequence repeat （SSR）] and cleaved amplified polymorphic se...The allelic variation of the Wx gene in 50 non-glutinous rice varieties （lines） was analyzed by using the microsatellite marker RM190 [for （CT）n simple sequence repeat （SSR）] and cleaved amplified polymorphic sequence（CAPS） marker 484/W2R-ACCⅠ[for G/T single nucleotide polymorphism （SNP）]. Six homozygous （CT）n types, namely （CT）20, （CT）19, （CT）18, （CT）17, （CT）16, （CT）14, （CT）11 and （CT）10, and a heterozygous genotype （CT）11/（CT）18 were detected for RM190, of which （CT）11 and （CT）18 were predominant. Two homozygous Wx genotypes （G/G and T/T） and one heterozygous （G/T） were detected using 484/W2R-ACC Ⅰ. Most of the materials with a RM190 of （CT）11 were G/G for SNP of 484/W2R-ACC Ⅰ, while T/T for SNP was predominantly appeared in materials with （CT）18. The materials tested could be grouped into 10 categories using the two markers together. Results indicated that 59.3% variance of amylose content was attributed to the polymorphism of Wx gene revealed by RM190, while 56.1% and 24.6% of the variances in amylose content and gel consistency were respectively to the polymorphism of Wx gene revealed by 484/W2R-ACC Ⅰ. Furthermore, with both SSR and CAPS markers, 72.4% of the variance in amylose content could be explained. In addition, the application prospects of the two markers in breeding were also discussed.展开更多
By means of topical application, fipronil resistance was surveyed in the rice stem borer, Chilo suppressalis, from 12 diferent areas in east China from 2001 to 2004. The rice stem borers in most regions of Jiangsu and...By means of topical application, fipronil resistance was surveyed in the rice stem borer, Chilo suppressalis, from 12 diferent areas in east China from 2001 to 2004. The rice stem borers in most regions of Jiangsu and Anhui were still susceptible to fipronil. But in Wuxi, Jiangsu Province and Cixi, Zhejiang Province, their sensitivity became decreased （resistance ratios were 3.1 and 3.6, respectively）, and the medium level of resistance （resistance ratio was 21.2） was found in Cangnan, Zhejiang Province. So, it was still at the early stage for fipronil resistance development in this pest. Synergism experiments showed that piperonyl butoxide（PBO） had a little effect on both susceptible and resistant borers （synergism ratios were 1.1-1.2）. Though triphenyl phosphate （TPP） and diethyl meleate （DEM） had no effect on the susceptible borers, they had significant synergism on fipronil in the resistant population to fipronil （synergism ratios were 1.8 and 1.6, respectively）, indicating esterase and glutathion S-transferase may be involved in the resistance mechanism. Bioassay with currently used insecticides indicated that triazophos （because of high resistance）, trichlorphon and acephate had very low toxicity to resistant borers. But diazinon, pyridaphenthion, decamethrin and avermeatin showed high toxicity and had no cross resistance to fipronil, which could be considered as substitute insecticides in the resistance managment.展开更多
A rice population consisting of 90 TN1/Guiyigu F3 lines was employed to analyze the linkage between DNA markers and a new gene Wbph6(t) conferring resistance to whitebacked planthopper, Sogatella furcifera By using th...A rice population consisting of 90 TN1/Guiyigu F3 lines was employed to analyze the linkage between DNA markers and a new gene Wbph6(t) conferring resistance to whitebacked planthopper, Sogatella furcifera By using the mapping approach of bulked extremes and recessive class, Wbph6(t) was mapped onto the short arm of chromosome 11 with a genetic distance of 21.2 cM to SSLP marker RM167.展开更多
A large number of plant remains were discovered in the ancient-woods layer of Zhujiajian Island, Zhejiang Province. There were some thick trunks, complete laminas, fruit, seeds and so on. According to radiocarbon test...A large number of plant remains were discovered in the ancient-woods layer of Zhujiajian Island, Zhejiang Province. There were some thick trunks, complete laminas, fruit, seeds and so on. According to radiocarbon tests conducted for plant remains, the ancient-woods layer has been dated back to about 8750 - 6200 years, and the vegetation was a subtropical evergreen and deciduous broad-leaved mixed forests on the island in the past. In the middle of the ancient-woods layer, two grains of wild rice were explored accidentally, which are Oryza rufipogon, along with the fruit and seeds of some water plants, such as Ceratophyllum demersum, C. oryzetorum, Euryale ferox, Trapa incisa var. quadricaudata , Scirpus yagara and so on. There might be marshy soil and a pond in ancient forest vegetation from where the grains of wild rice and hydrophytic fruit were found. It is of tremendous importance to study the origin of wild rice in China.展开更多
Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique ...Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.展开更多
The rice false smut disease, caused by Ustilaginoidea virens, has emerged as a significantglobal threat to rice production. The mechanism of carbon catabolite repression plays a crucial role in theefficient utilizatio...The rice false smut disease, caused by Ustilaginoidea virens, has emerged as a significantglobal threat to rice production. The mechanism of carbon catabolite repression plays a crucial role in theefficient utilization of carbon nutrients and enzyme regulation in the presence of complex nutritionalconditions. Although significant progress has been made in understanding carbon catabolite repression infungi such as Aspergillus nidulans and Magnaporthe oryzae, its role in U. virens remains unclear. Toaddress this knowledge gap, we identified UvCreA, a pivotal component of carbon catabolite repression,in U. virens. Our investigation revealed that UvCreA localized to the nucleus. Deletion of UvCreA resultedin decreased growth and pathogenicity in U. virens. Through RNA-seq analysis, it was found that theknockout of UvCreA led to the up-regulation of 514 genes and down-regulation of 640 genes. Moreover,UvCreA was found to be involved in the transcriptional regulation of pathogenic genes and genesassociated with carbon metabolism in U. virens. In summary, our findings indicated that UvCreA isimportant in fungal development, virulence, and the utilization of carbon sources through transcriptionalregulation, thus making it a critical element of carbon catabolite repression.展开更多
Nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+))are two main inorganic nitrogen(N)sources during crop growth.Here,we enhanced the expression of OsAMT1.1,which encodes a NH_(4)^(+)transporter,using the NO_(3)^(-)-inducible ...Nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+))are two main inorganic nitrogen(N)sources during crop growth.Here,we enhanced the expression of OsAMT1.1,which encodes a NH_(4)^(+)transporter,using the NO_(3)^(-)-inducible promoter of OsNAR2.1 and an ubiquitin promoter in transgenic rice plants.Under field condition of 120 kg/hm2 N,agronomic N use efficiency,N recovery efficiency and N transport efficiency,and grain yield of the pOsNAR2.1:OsAMT1.1 transgenic lines were increased compared with those of the wild type(WT)and the pUbi:OsAMT1.1 transgenic plants.Under 2.0 mmol/L NO_(3)^(-)+0.5 mmol/L NH_(4)^(+)and 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)conditions of hydroponic culture,compared with the WT,both biomass and total N content were increased in the pOsNAR2.1:OsAMT1.1 transgenic lines.However,biomass was significantly reduced in pUbi:OsAMT1.1 transgenic plants under 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)condition.The lines expressing pOsNAR2.1:OsAMT1.1 exhibited increased OsAMT1.1 expression and 15NH_(4)^(+)influx in roots under both 2.0 mmol/L NO_(3)^(-)+0.5 mmol/L NH_(4)^(+)and 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)conditions.Our study showed that expression of OsAMT1.1 can be promoted when driven by the OsNAR2.1 promoter,especially under high-level nitrate condition,leading to enhancement of NH_(4)^(+)uptake,N use efficiency and grain yield.展开更多
The abundant genetic resources of wild rice in China represent a key gene pool for modern rice breeding,contributing to food production and agricultural development in China and worldwide.Between the 1970s and the 201...The abundant genetic resources of wild rice in China represent a key gene pool for modern rice breeding,contributing to food production and agricultural development in China and worldwide.Between the 1970s and the 2010s,two national wild rice surveys were carried out in China.More than 20000accessions of three species Oryza rufipogon,O.officinalis and O.meyeriana have been conserved ex situ.An in situ conservation system has also been set up to protect notable and endangered populations.This review summarized the geographical distribution of wild rice in China,the current status of conservation,the discovery of elite genes,and the application of research into the origin and domestication of rice.展开更多
Grain germination is a process involving numerous factors that influence the biochemical processes inside the plant cells.This review covered the abiotic factors that lead to the germination and significantly impact t...Grain germination is a process involving numerous factors that influence the biochemical processes inside the plant cells.This review covered the abiotic factors that lead to the germination and significantly impact the nutritional properties and digestion behavior of rice grains.The macro-and micro-nutrients can be changed depending on the intensity of the applied variables during germination.For instance,germination time can increase the protein content in the grain and concurrently reduce its protein digestibility.In most cases,the number of bioactive compounds present in rice grains are increased regardless of germination conditions.Germination can promote the complexation of nutrients and thus negatively interfere with the digestibility of macronutrients.This review highlighted the influence of the germination process on the nutritional quality of rice grains,providing information about the germination conditions and their impacts on the anabolic and catabolic reactions of the grain,emphasizing the health benefits.展开更多
Rice(Oryza sativa L.)is grown nearly worldwide and provides the staple food for more than half of the global population(Luo et al,2017).The genomes of several cultivated rice varieties including Nipponbare(NPB)(Kawaha...Rice(Oryza sativa L.)is grown nearly worldwide and provides the staple food for more than half of the global population(Luo et al,2017).The genomes of several cultivated rice varieties including Nipponbare(NPB)(Kawahara et al,2013;Sakai et al,2013),IR64(Tanaka et al,2020),93-11(Zhang et al,2018)and R498(Du et al,2017)at chromosome level,and Minghui 63 and Zhenshan 97(Zhang et al,2016)at scaffold level have been assembled,annotated and released,among which the R498 and NPB genomes are widely used as reference genomes in rice research.However,there are thousands of rice cultivars,landraces and wild rice varieties in the world with dramatically different genetic backgrounds,and the genomes of native rice varieties in South China,which is one of the major rice production areas in China,have not been de novo assembled.Huajingxian 74(HJX74)is an indica rice variety bred in South China Agricultural University,Guangdong Province with widely environmental adaptability and high yield(www.ricedata.cn/variety/varis/602548.htm).HJX74 exhibits significant phenotypic and genetic differences from those varieties whose whole genomes have been properly sequenced and assembled(Fig.1).展开更多
Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were ana...Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were analyzed using a recombinant inbred line(RIL)population derived from a cross between PA64s and 93-11.A total of 36 QTLs associated with shoot length,root length,shoot dry weight,root dry weight and total dry weight were detected in Hangzhou and Lingshui of China.Among them,15 QTLs were identified under the control condition and 15 QTLs were identified under the Cd stress condition,and 6 QTLs for Cd tolerant coefficient were detected on chromosomes 1,3,7 and 9.The qCDSL1.1 and qCDSL1.2 were identified in Hangzhou and Lingshui,respectively,and had overlapping intervals on chromosome 1.To further confirm the effects of qCDSL1.1 and qCDSL1.2,we developed a chromosome segment substitution line(CSSL),CSSLqCDSL1,in 93-11 background harboring qCDSL1.1/qCDSL1.2 from PA64s.Compared to 93-11,CSSLqCDSL1 had increased shoot length under the Cd stress condition.These results pave the way for further isolation of those genes controlling Cd tolerance in rice and marker-assistant selection of rice elite varieties with Cd tolerance.展开更多
基金supported by the Hubei Provincial Natural Science Foundation,China(Grant No.2024AFB917).
文摘As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice.
文摘The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases.Meeting the rice demand domestically has remained challenging due to significant yield loss caused by several biotic and abiotic factors.Among these factors,one of the most important is the high weed pressure that ravages the upland rice ecology.In Nigeria,several independent weed control techniques,such as physical,chemical and cultural methods,have been recommended and adopted for weed control across varying rice upland ecologies.However,outcomes of these approaches when used independently have not consistently led to an increase in yield.There remains an outstanding deficit between the actual yield and the potential rice yield.This review aimed to identify potential research gaps,and quest effective and sustainable weed management strategies in smallholder upland rice farming systems in Nigeria.A critical analysis of studies suggests the potential of sustainable weed management practices if adopted and adapted smartly in different upland ecologies in Nigeria.Competitiveness of upland rice against weeds can be enhanced through strategic integration of weed competitive cultivars,optimum nitrogen application timings(within weed-free periods),uniform plant spacing,and high seeding rates,with conventional herbicide/manual weed control practices.However,such management practices can only be engaged where inputs are supplied on time and the technical know-how is extended to farmers.The review equally highlights potential research gaps for further studies.
文摘SCOPE Rice Science is an international peer-reviewed journal sponsored by China National Rice Research Institute and hosting by Elsevier B V It publishes original research papers,review articles,short communications as well as letters on rice science in English language.Some of the topics that may be included in each issue are:breeding and genetics,biotechnology,germplasm resources,agronomy,pest management,soil and fertilizer management and cereal chemistry.The full texts of Rice Science are available online at http://www.ricescience.org or http://www.sciencedirect.com/joumal/rice-science.
文摘Rice germplasm A total of 208 indica P/TGMS lines were selected for analysis from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 2), and 100 typical indica and 100 japonica accessions to identify the indica/japonica component of them were also from the National Mid-term Genebank for Rice, Hangzhou, China (Supplemental Table 5).
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.31171485 and 31470086)the National High Technology Research and Development Program of China(Grant No.2014AA10A605)the National Science and Technology Supporting Program of China(Grant Nos.2012BAD04B08 and 2013BAD07B09)
文摘To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains（PCG）, brown rice yield（BRY）, milled rice yield（MRY）, degree of milling（DM）, amylose content（AC）, protein content（PC）, and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size（grain length ≤ 5.5 mm） and bold shape（grain length to width ratio = 1.10-2.00）. Most of rice mutants（87.5%） had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.
基金supported by the Key Project of the National Twelve-Five Year Research Program of China(Grant No.2012BAD20B05-01-1)the Projects from the National Rice Industrial Technology System(Grant No.nycytx-001)the Grant Special Foundation of Transgenic Plants in China(Grant No.2009ZX08001-009B)
文摘Nine CBF/DREB1 homologous genes in rice were obtained by BLAST search in the NCBI database, which share conserved amino acid sequences with DREB1 protein in Arabidopsis. Three CBF genes organized in tandem, named OsCBF1, OsCBF2 and OsCBF3, showed a transient induction in the process of cold acclimation, much stronger in indica rice 93-11 compared with japonica rice Nipponbare. The candidate downstream genes OsLIP5 and OsLIP9 were induced in 93-11 but not in Nipponbare. The differential expression of CBF regulon might be caused by polymorphisms within promoter sequences between these two rice varieties. These results could be useful for utilization of CBF/DREB1 genes and illustration of differences in chilling tolerance between indica and japonica rice varieties.
文摘The newly-hatched nymphs of the small brown planthopper (SBPH), Laodelphax striatellus, including field and sensitive populations, were subjected to the high-temperature (35°C) treatment. The number of yeast-like endosymbiotes in SBPH reduced by 23.47%–34.23%, 57.86%–61.51% and 88.96%–90.71% after the high-temperature treatment for 1 d, 2 d, and 3 d, respectively. However, the size of yeast-like endosymbiotes was not obviously affected. Resistance of SBPH to three insecticides (imidacloprid, chlorpyrifos and fipronil) decreased with the increase of treatment time.
基金This work was supported by the National Natural Science Foundation of China(Grant No.30460065)Yunnan Provincial Foundation for Science.
文摘The genetic diversity of the 34 populations of wild rice Oryza meyeriana Baill. distributed in Yunnan Province, China was analyzed using 13 inter-simple sequence repeat （ISSR） markers. A total of 168 bands were amplified, of which 135 polymorphic bands were discovered and the percentage of polymorphic bands （PPB） was 80.36%. A genetic diversity was revealed as Nei＇s gene diversity （H） = 0.2666 and Shannon information index （I） = 0.4028 at population level. The 34 populations were divided into different groups based on administrative regions, latitude and longitudes, river areas, altitudes of their origins, and their indexes such as Na （number of alleles）, Ne （effective number of alleles）, H, I and PPB were calculated. Richer genetic diversity was found in the wild rice populations distributed in Simao Prefecture than that in Lingcang Prefecture or Xishuangbanna Prefecture whereas the least genetic diversity was in Baoshan Prefecture or Dehong Prefecture. Rich genetic diversity was also discovered in the wild rice populations originated from higher than 710 m altitude around the middle and lower reaches of the Lancang River belonging to the Pacific Ocean drainage system. The 34 populations could be classified into two groups, one group covered the wild rice distributing in Simao Prefecture only while the other group covered ones in Lingcang, Xishuangbanna and Dehong Prefectures. The issue on how to effectively conserve the wild rice germplasm was discussed.
文摘The allelic variation of the Wx gene in 50 non-glutinous rice varieties （lines） was analyzed by using the microsatellite marker RM190 [for （CT）n simple sequence repeat （SSR）] and cleaved amplified polymorphic sequence（CAPS） marker 484/W2R-ACCⅠ[for G/T single nucleotide polymorphism （SNP）]. Six homozygous （CT）n types, namely （CT）20, （CT）19, （CT）18, （CT）17, （CT）16, （CT）14, （CT）11 and （CT）10, and a heterozygous genotype （CT）11/（CT）18 were detected for RM190, of which （CT）11 and （CT）18 were predominant. Two homozygous Wx genotypes （G/G and T/T） and one heterozygous （G/T） were detected using 484/W2R-ACC Ⅰ. Most of the materials with a RM190 of （CT）11 were G/G for SNP of 484/W2R-ACC Ⅰ, while T/T for SNP was predominantly appeared in materials with （CT）18. The materials tested could be grouped into 10 categories using the two markers together. Results indicated that 59.3% variance of amylose content was attributed to the polymorphism of Wx gene revealed by RM190, while 56.1% and 24.6% of the variances in amylose content and gel consistency were respectively to the polymorphism of Wx gene revealed by 484/W2R-ACC Ⅰ. Furthermore, with both SSR and CAPS markers, 72.4% of the variance in amylose content could be explained. In addition, the application prospects of the two markers in breeding were also discussed.
基金the Key Technologies R&D Programme of the Tenth Five—Years Plan(2001BA509B08)Science and Technology Engineering Programme for Promoting Crop Yield(2004BA520Al5) Youth Foundation of Nanjing Agricultural University (020600247).
文摘By means of topical application, fipronil resistance was surveyed in the rice stem borer, Chilo suppressalis, from 12 diferent areas in east China from 2001 to 2004. The rice stem borers in most regions of Jiangsu and Anhui were still susceptible to fipronil. But in Wuxi, Jiangsu Province and Cixi, Zhejiang Province, their sensitivity became decreased （resistance ratios were 3.1 and 3.6, respectively）, and the medium level of resistance （resistance ratio was 21.2） was found in Cangnan, Zhejiang Province. So, it was still at the early stage for fipronil resistance development in this pest. Synergism experiments showed that piperonyl butoxide（PBO） had a little effect on both susceptible and resistant borers （synergism ratios were 1.1-1.2）. Though triphenyl phosphate （TPP） and diethyl meleate （DEM） had no effect on the susceptible borers, they had significant synergism on fipronil in the resistant population to fipronil （synergism ratios were 1.8 and 1.6, respectively）, indicating esterase and glutathion S-transferase may be involved in the resistance mechanism. Bioassay with currently used insecticides indicated that triazophos （because of high resistance）, trichlorphon and acephate had very low toxicity to resistant borers. But diazinon, pyridaphenthion, decamethrin and avermeatin showed high toxicity and had no cross resistance to fipronil, which could be considered as substitute insecticides in the resistance managment.
文摘A rice population consisting of 90 TN1/Guiyigu F3 lines was employed to analyze the linkage between DNA markers and a new gene Wbph6(t) conferring resistance to whitebacked planthopper, Sogatella furcifera By using the mapping approach of bulked extremes and recessive class, Wbph6(t) was mapped onto the short arm of chromosome 11 with a genetic distance of 21.2 cM to SSLP marker RM167.
文摘A large number of plant remains were discovered in the ancient-woods layer of Zhujiajian Island, Zhejiang Province. There were some thick trunks, complete laminas, fruit, seeds and so on. According to radiocarbon tests conducted for plant remains, the ancient-woods layer has been dated back to about 8750 - 6200 years, and the vegetation was a subtropical evergreen and deciduous broad-leaved mixed forests on the island in the past. In the middle of the ancient-woods layer, two grains of wild rice were explored accidentally, which are Oryza rufipogon, along with the fruit and seeds of some water plants, such as Ceratophyllum demersum, C. oryzetorum, Euryale ferox, Trapa incisa var. quadricaudata , Scirpus yagara and so on. There might be marshy soil and a pond in ancient forest vegetation from where the grains of wild rice and hydrophytic fruit were found. It is of tremendous importance to study the origin of wild rice in China.
基金supported by the National Key Resarch and Development Program of China(Grant No.2023YFD1200802)the Base Bank of Lingnan Rice Germplasm Resources Project,China(Grant No.2024B1212060009).
文摘Polyploidization is a commonly employed strategy in crop breeding to augment genetic diversity,particularly leveraging the distinctive benefits of additional progressive heterosis or multi-generation heterosis unique to polyploidy.Despite genetic disparities between polyploids and diploids,challenges stem from reproductive anomalies,complicating genetic investigations in polyploid systems.Through nearly two decades of intensive research,our team has effectively generated a series of fertile tetraploid lines known as neo-tetraploid rice(NTR),facilitating comparative genetic studies between diploid and tetraploid rice.In this study,we identified diploid counterparts(H3d and H8d)for two NTR lines[Huaduo 3(H3)and Huaduo 8(H8)]and utilized them to create diploid and tetraploid fertile F_(2) populations to assess genotype segregation ratios,recombination rates,and their impact on QTL mapping via bulked segregant analysis combined with sequencing(BSA-seq).Additionally,we assessed yield heterosis in F_(1) and F_(2) generations of two tetraploid populations(H3×H8 and T449×H1),revealing evidence of multi-generation heterosis in polyploid rice.These findings provide valuable insights into the advantages and challenges of polyploid rice breeding.
基金the Key Projects of Zhejiang Provincial Natural Science Foundation,China(Grant No.LZ23C130002)the National Natural Science Foundation of China(Grant No.32100161)+3 种基金the Zhejiang Science and Technology Major Program on Rice New Variety Breeding,China(Grant No.2021C02063)the Key R&D Project of China National Rice Research Institute(Grant No.CNRRI-2020-04)the Chinese Academy of Agricultural Sciences under the Agricultural Sciences and Technologies Innovation Program,the Youth innovation Program of Chinese Academy of Agricultural Sciences(Grant No.Y2023QC22)the Joint Open Competitive Project of the Yazhou Bay Seed Laboratory and China National Seed Company Limited(Grant Nos.B23YQ1514 and B23CQ15EP).
文摘The rice false smut disease, caused by Ustilaginoidea virens, has emerged as a significantglobal threat to rice production. The mechanism of carbon catabolite repression plays a crucial role in theefficient utilization of carbon nutrients and enzyme regulation in the presence of complex nutritionalconditions. Although significant progress has been made in understanding carbon catabolite repression infungi such as Aspergillus nidulans and Magnaporthe oryzae, its role in U. virens remains unclear. Toaddress this knowledge gap, we identified UvCreA, a pivotal component of carbon catabolite repression,in U. virens. Our investigation revealed that UvCreA localized to the nucleus. Deletion of UvCreA resultedin decreased growth and pathogenicity in U. virens. Through RNA-seq analysis, it was found that theknockout of UvCreA led to the up-regulation of 514 genes and down-regulation of 640 genes. Moreover,UvCreA was found to be involved in the transcriptional regulation of pathogenic genes and genesassociated with carbon metabolism in U. virens. In summary, our findings indicated that UvCreA isimportant in fungal development, virulence, and the utilization of carbon sources through transcriptionalregulation, thus making it a critical element of carbon catabolite repression.
基金financially supported by the National Natural Science Foundation of China(Grant No.32061143039)Guangdong Basic and Applied Basic Research Foundation,China(Grant No.2022A1515012381)+1 种基金Shenzhen Science and Technology Program,China(Grant No.JCYJ20210324124409027)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University,China.
文摘Nitrate(NO_(3)^(-))and ammonium(NH_(4)^(+))are two main inorganic nitrogen(N)sources during crop growth.Here,we enhanced the expression of OsAMT1.1,which encodes a NH_(4)^(+)transporter,using the NO_(3)^(-)-inducible promoter of OsNAR2.1 and an ubiquitin promoter in transgenic rice plants.Under field condition of 120 kg/hm2 N,agronomic N use efficiency,N recovery efficiency and N transport efficiency,and grain yield of the pOsNAR2.1:OsAMT1.1 transgenic lines were increased compared with those of the wild type(WT)and the pUbi:OsAMT1.1 transgenic plants.Under 2.0 mmol/L NO_(3)^(-)+0.5 mmol/L NH_(4)^(+)and 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)conditions of hydroponic culture,compared with the WT,both biomass and total N content were increased in the pOsNAR2.1:OsAMT1.1 transgenic lines.However,biomass was significantly reduced in pUbi:OsAMT1.1 transgenic plants under 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)condition.The lines expressing pOsNAR2.1:OsAMT1.1 exhibited increased OsAMT1.1 expression and 15NH_(4)^(+)influx in roots under both 2.0 mmol/L NO_(3)^(-)+0.5 mmol/L NH_(4)^(+)and 0.5 mmol/L NO_(3)^(-)+2.0 mmol/L NH_(4)^(+)conditions.Our study showed that expression of OsAMT1.1 can be promoted when driven by the OsNAR2.1 promoter,especially under high-level nitrate condition,leading to enhancement of NH_(4)^(+)uptake,N use efficiency and grain yield.
基金supported by the National Natural Science Foundation of China(Grant No.31471471)the Project of Sanya Yazhou Bay Science and Technology City,China(Grant No.SKJC-2020-02-001)。
文摘The abundant genetic resources of wild rice in China represent a key gene pool for modern rice breeding,contributing to food production and agricultural development in China and worldwide.Between the 1970s and the 2010s,two national wild rice surveys were carried out in China.More than 20000accessions of three species Oryza rufipogon,O.officinalis and O.meyeriana have been conserved ex situ.An in situ conservation system has also been set up to protect notable and endangered populations.This review summarized the geographical distribution of wild rice in China,the current status of conservation,the discovery of elite genes,and the application of research into the origin and domestication of rice.
基金FAPERGS(Research Support Foundation of the State of Rio Grande do Sul)CAPES(Coordination of Improvement of Higher Education Personnel)+1 种基金CNPq(National Council for Scientific and Technological Development)SCT-RS(Secretary of Science and Technology of the State of Rio Grande do Sul)for the financial support。
文摘Grain germination is a process involving numerous factors that influence the biochemical processes inside the plant cells.This review covered the abiotic factors that lead to the germination and significantly impact the nutritional properties and digestion behavior of rice grains.The macro-and micro-nutrients can be changed depending on the intensity of the applied variables during germination.For instance,germination time can increase the protein content in the grain and concurrently reduce its protein digestibility.In most cases,the number of bioactive compounds present in rice grains are increased regardless of germination conditions.Germination can promote the complexation of nutrients and thus negatively interfere with the digestibility of macronutrients.This review highlighted the influence of the germination process on the nutritional quality of rice grains,providing information about the germination conditions and their impacts on the anabolic and catabolic reactions of the grain,emphasizing the health benefits.
基金the National Key Research and Development Program of China(Grant No.2016YFD0100406)National College Students Innovation and Entrepreneurship Foundation of China(Grant No.201910564054)+1 种基金National Natural Science Foundation of China(Grant Nos.91735304 and 31622041)Special Project for Leading Talents in Innovation of Science and Technology of Guangdong Province,China(Grant No.2016TX03N224)。
文摘Rice(Oryza sativa L.)is grown nearly worldwide and provides the staple food for more than half of the global population(Luo et al,2017).The genomes of several cultivated rice varieties including Nipponbare(NPB)(Kawahara et al,2013;Sakai et al,2013),IR64(Tanaka et al,2020),93-11(Zhang et al,2018)and R498(Du et al,2017)at chromosome level,and Minghui 63 and Zhenshan 97(Zhang et al,2016)at scaffold level have been assembled,annotated and released,among which the R498 and NPB genomes are widely used as reference genomes in rice research.However,there are thousands of rice cultivars,landraces and wild rice varieties in the world with dramatically different genetic backgrounds,and the genomes of native rice varieties in South China,which is one of the major rice production areas in China,have not been de novo assembled.Huajingxian 74(HJX74)is an indica rice variety bred in South China Agricultural University,Guangdong Province with widely environmental adaptability and high yield(www.ricedata.cn/variety/varis/602548.htm).HJX74 exhibits significant phenotypic and genetic differences from those varieties whose whole genomes have been properly sequenced and assembled(Fig.1).
基金the National Natural Science Foundation of China(Grant No.31671761)the Agricultural Science and Technology Innovation Program,Shenzhen Science and Technology Program(Grant No.2017050414212249).
文摘Cadmium(Cd)is a non-essential toxic metal that is harmful to plants.To investigate the genetic mechanism of Cd tolerance in rice,quantitative trait loci(QTLs)associated with Cd tolerance at the seedling stage were analyzed using a recombinant inbred line(RIL)population derived from a cross between PA64s and 93-11.A total of 36 QTLs associated with shoot length,root length,shoot dry weight,root dry weight and total dry weight were detected in Hangzhou and Lingshui of China.Among them,15 QTLs were identified under the control condition and 15 QTLs were identified under the Cd stress condition,and 6 QTLs for Cd tolerant coefficient were detected on chromosomes 1,3,7 and 9.The qCDSL1.1 and qCDSL1.2 were identified in Hangzhou and Lingshui,respectively,and had overlapping intervals on chromosome 1.To further confirm the effects of qCDSL1.1 and qCDSL1.2,we developed a chromosome segment substitution line(CSSL),CSSLqCDSL1,in 93-11 background harboring qCDSL1.1/qCDSL1.2 from PA64s.Compared to 93-11,CSSLqCDSL1 had increased shoot length under the Cd stress condition.These results pave the way for further isolation of those genes controlling Cd tolerance in rice and marker-assistant selection of rice elite varieties with Cd tolerance.
