Cleistogamy involves the shedding of pollen within an enclosed flower. In barley, this trait is determined by the presence of a recessive allele at the gene Clyl, a member of the AP2 gene family. Here we show that the...Cleistogamy involves the shedding of pollen within an enclosed flower. In barley, this trait is determined by the presence of a recessive allele at the gene Clyl, a member of the AP2 gene family. Here we show that the Clyl ortholog in einkorn （diploid） wheat （Triticum monococcum） TmAP2 shares a similar structure and identical pattern of transcription as Clyl. The transcript abundance of TmAP2 was high in the spike around the time of anthesis, but low in the leaf, plumule and radicle. The TmAP2 transcript was cleaved at its miR172 target site. Flower gaping at anthesis in einkorn wheat is induced by the expansion of the lodicules.展开更多
Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen v...Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen virulence.Thus,exploration and characterization of new resistance genes is always ongoing.Line NJ3946 derived from a cross of einkorn wheat accessions TA2032 and M389 showed resistance to powdery mildew.Inheritance analysis of an F2 population derived from a cross of NJ3946 and M389 suggested that the resistance was conferred by a dominant allele.With polymorphic markers identified through bulked segregant analysis(BSA),this gene was mapped to a novel locus on chromosome 3A,and was designated as PmNJ3946.Bulked segregant RNA-seq analysis(BSR-seq)was conducted to obtain more closely linked markers,which allowed delimitation of the PMNJ3946 locus to a 0.9 cM interval covering a physical distance of less than 1 Mb.PMNJ3946 was flanked by Xwgrc5153 and SNP-derived marker CHS21_3A008915069,and co-segregated with SNP-derived markers CHS21_3A008939814 and CHS21_3A008943175.The PmNJ3946 discovery expands the diversity of powdery mildew resistance genes and is useful for wheat breeding.展开更多
In wheat plants at the vegetative growth stage, the shoot apical meristem (SAM) produces leaf primordia. When reproductive growth is initiated, the SAM forms an inflorescence meristem (IM) that differentiates a series...In wheat plants at the vegetative growth stage, the shoot apical meristem (SAM) produces leaf primordia. When reproductive growth is initiated, the SAM forms an inflorescence meristem (IM) that differentiates a series of spikelet meristem (SM) as the branch. The SM then produces a series of floret meristem (FM) as the branch. To identify the mechanisms that regulate formation of the reproductive meristems in wheat, we have investigated a leaf initiation mutant, fushi-darake (fdk) which was developed by ion beam mutagenesis. The morphological traits were compared in wild type (WT) and fdk mutant plants grown in the experimental field. WT plants initiated leaves from SAM at regular intervals in spiral phyllotaxy, while fdk plants had 1/2 alternate phyllotaxy with rapid leaf emergence. The fdk plants have increased numbers of nodes and leaves compared with WT plants. The time interval between successive leaf initiation events (plastochron) was measured in plants grown in a growth chamber. The fdk plants clearly show the rapid leaf emergence, indicating a shortened plastochron. Each tiller in fdk plants branches at the upper part of the culm. The fine structure of organ formation in meristems of fdk plants was examined by scanning electron microscopy (SEM). The SEM analysis indicated that fdk plants show transformation of spikelet meristems into vegetative shoot meristems. In conclusion, the fdk mutant has a heterochronic nature, i.e., both reproductive and vegetative programs were simultaneously in operation during the reproductive phase, resulting in a shortened plastochron and transformation of reproductive spikelets into vegetative shoots.展开更多
Clear G-bands were revealed by applying the TUG method on chromosomes of 5 species of higher plants (Lilium davdii, Viciafaba, Hordeum vulgare, Ginkgo biloba and Triticum monococcam). Some details of the TUG method wh...Clear G-bands were revealed by applying the TUG method on chromosomes of 5 species of higher plants (Lilium davdii, Viciafaba, Hordeum vulgare, Ginkgo biloba and Triticum monococcam). Some details of the TUG method which consisted of treating chromosomes with both trypsin and urea were also studied. The mechanisms that might account for the presence of G-bands in plants were discussed.展开更多
Species closely related to wheat are important genetic resources for agricultural production,functional genomics studies and wheat improvement.In this study,a wheat gene related to regeneration,TaWOX5,was applied to e...Species closely related to wheat are important genetic resources for agricultural production,functional genomics studies and wheat improvement.In this study,a wheat gene related to regeneration,TaWOX5,was applied to establish the Agrobacterium-mediated transformation systems of Triticum monococcum,hexaploid triticale,and rye(Secale cereale L.)using their immature embryos.Transgenic plants were efficiently generated.During the transformation process,the Agrobacterium infection efficiency was assessed by histochemical staining forβ-glucuronidase(GUS).Finally,the transgenic nature of regenerated plants was verified by polymerase chain reaction(PCR)-based genotyping for the presence of the GUS and bialaphos resistance(bar)genes,histochemical staining for GUS protein,and the QuickStix strip assay for bar protein.The transformation efficiency of T.monococcum genotype PI428182 was 94.4%;the efficiencies of four hexaploid triticale genotypes Lin456,ZS3297,ZS1257,and ZS3224 were 52.1,41.2,19.4,and 16.0%,respectively;and the transformation efficiency of rye cultivar Lanzhou Heimai was 7.8%.Fluorescence in situ hybridization(FISH)and genomic in situ hybridization(GISH)analyses indicated that the GUS transgenes were integrated into the distal or near centromere(proximal)regions of the chromosomes in transgenic T.monococcum and hexaploid triticale plants.In the transgenic hexaploid triticale plants,the foreign DNA fragment was randomly integrated into the AABB and RR genomes.Furthermore,the transgene was almost stably inherited in the next generation by Mendel’s law.The findings in this study will promote the genetic improvement of the three plant species for grain or forage production and the improvement of cereal species including wheat for functional genomics studies.展开更多
基金funded by the Japanese Ministry of Agriculture,Forestry and Fisheries (Genomics for Agricultural Innovation Grants No.TRG1004) to T.K.S.N.appreciates the award of a Japanese Government (Monbukagakusho:MEXT) scholarship
文摘Cleistogamy involves the shedding of pollen within an enclosed flower. In barley, this trait is determined by the presence of a recessive allele at the gene Clyl, a member of the AP2 gene family. Here we show that the Clyl ortholog in einkorn （diploid） wheat （Triticum monococcum） TmAP2 shares a similar structure and identical pattern of transcription as Clyl. The transcript abundance of TmAP2 was high in the spike around the time of anthesis, but low in the leaf, plumule and radicle. The TmAP2 transcript was cleaved at its miR172 target site. Flower gaping at anthesis in einkorn wheat is induced by the expansion of the lodicules.
基金the‘JBGS’Project of Seed Industry Revitalization in Jiangsu Province(JBGS(2021)013)National Natural Science Foundation of Jiangsu Province for Young Scholars(BK20170176)+2 种基金National Natural Science Foundation of China(30771165)the Ministry of Science and Technology of China(2016YFD0101004)Jiangsu Collaborative Innovation Initiative for Modern Crop Production.
文摘Powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is a destructive wheat disease.Although it can be easily overcome by deployment of resistance genes,the resistance is often quickly compromised by pathogen virulence.Thus,exploration and characterization of new resistance genes is always ongoing.Line NJ3946 derived from a cross of einkorn wheat accessions TA2032 and M389 showed resistance to powdery mildew.Inheritance analysis of an F2 population derived from a cross of NJ3946 and M389 suggested that the resistance was conferred by a dominant allele.With polymorphic markers identified through bulked segregant analysis(BSA),this gene was mapped to a novel locus on chromosome 3A,and was designated as PmNJ3946.Bulked segregant RNA-seq analysis(BSR-seq)was conducted to obtain more closely linked markers,which allowed delimitation of the PMNJ3946 locus to a 0.9 cM interval covering a physical distance of less than 1 Mb.PMNJ3946 was flanked by Xwgrc5153 and SNP-derived marker CHS21_3A008915069,and co-segregated with SNP-derived markers CHS21_3A008939814 and CHS21_3A008943175.The PmNJ3946 discovery expands the diversity of powdery mildew resistance genes and is useful for wheat breeding.
文摘In wheat plants at the vegetative growth stage, the shoot apical meristem (SAM) produces leaf primordia. When reproductive growth is initiated, the SAM forms an inflorescence meristem (IM) that differentiates a series of spikelet meristem (SM) as the branch. The SM then produces a series of floret meristem (FM) as the branch. To identify the mechanisms that regulate formation of the reproductive meristems in wheat, we have investigated a leaf initiation mutant, fushi-darake (fdk) which was developed by ion beam mutagenesis. The morphological traits were compared in wild type (WT) and fdk mutant plants grown in the experimental field. WT plants initiated leaves from SAM at regular intervals in spiral phyllotaxy, while fdk plants had 1/2 alternate phyllotaxy with rapid leaf emergence. The fdk plants have increased numbers of nodes and leaves compared with WT plants. The time interval between successive leaf initiation events (plastochron) was measured in plants grown in a growth chamber. The fdk plants clearly show the rapid leaf emergence, indicating a shortened plastochron. Each tiller in fdk plants branches at the upper part of the culm. The fine structure of organ formation in meristems of fdk plants was examined by scanning electron microscopy (SEM). The SEM analysis indicated that fdk plants show transformation of spikelet meristems into vegetative shoot meristems. In conclusion, the fdk mutant has a heterochronic nature, i.e., both reproductive and vegetative programs were simultaneously in operation during the reproductive phase, resulting in a shortened plastochron and transformation of reproductive spikelets into vegetative shoots.
文摘Clear G-bands were revealed by applying the TUG method on chromosomes of 5 species of higher plants (Lilium davdii, Viciafaba, Hordeum vulgare, Ginkgo biloba and Triticum monococcam). Some details of the TUG method which consisted of treating chromosomes with both trypsin and urea were also studied. The mechanisms that might account for the presence of G-bands in plants were discussed.
基金supported by grants from the National Natural Science Foundation of China(31971946)the Technology Innovation Program of the Chinese Academy of Agricultural Sciences,China(2060302-2-23,ASTIP-2060302-2-19).
文摘Species closely related to wheat are important genetic resources for agricultural production,functional genomics studies and wheat improvement.In this study,a wheat gene related to regeneration,TaWOX5,was applied to establish the Agrobacterium-mediated transformation systems of Triticum monococcum,hexaploid triticale,and rye(Secale cereale L.)using their immature embryos.Transgenic plants were efficiently generated.During the transformation process,the Agrobacterium infection efficiency was assessed by histochemical staining forβ-glucuronidase(GUS).Finally,the transgenic nature of regenerated plants was verified by polymerase chain reaction(PCR)-based genotyping for the presence of the GUS and bialaphos resistance(bar)genes,histochemical staining for GUS protein,and the QuickStix strip assay for bar protein.The transformation efficiency of T.monococcum genotype PI428182 was 94.4%;the efficiencies of four hexaploid triticale genotypes Lin456,ZS3297,ZS1257,and ZS3224 were 52.1,41.2,19.4,and 16.0%,respectively;and the transformation efficiency of rye cultivar Lanzhou Heimai was 7.8%.Fluorescence in situ hybridization(FISH)and genomic in situ hybridization(GISH)analyses indicated that the GUS transgenes were integrated into the distal or near centromere(proximal)regions of the chromosomes in transgenic T.monococcum and hexaploid triticale plants.In the transgenic hexaploid triticale plants,the foreign DNA fragment was randomly integrated into the AABB and RR genomes.Furthermore,the transgene was almost stably inherited in the next generation by Mendel’s law.The findings in this study will promote the genetic improvement of the three plant species for grain or forage production and the improvement of cereal species including wheat for functional genomics studies.
