Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with ...Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.展开更多
mtDNAs of T type wheat cytoplasmic male sterile lines Ning Drawf 14(ND14) and their maintainers Ning Drawf 13 (ND13) were isolated and digested completely with restriction endonucleases EcoRI, PstI, EcoRV, BamHI. The ...mtDNAs of T type wheat cytoplasmic male sterile lines Ning Drawf 14(ND14) and their maintainers Ning Drawf 13 (ND13) were isolated and digested completely with restriction endonucleases EcoRI, PstI, EcoRV, BamHI. The results revealed that the molecular structure of mtDNAs from ND14 and ND13 cytoplasms were significantly deviated. The mitochondrial genomic difference between CMS line and maintainers were uncovered by southern hybridization with probes of 18S+5S rRNA、atpA genes from wheat and pea mitochondria, respectively. Due to the complexity of mtDNA and no proof of protein difference, it has not yet been demonstrated whether mtDNA difference of Normal and Male Sterile Cytoplasm of wheat is associated with CMS.展开更多
[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum a...[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line,the analysis methods such as chromosome C-banding,genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS)was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS.展开更多
Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants rese...Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants resembling wheat morphology were obtained. The F-2 hybrid plants could be divided into 3 types according to their morphology. Type I hybrids had high and loosely standing stalks with big spikes and grains. Type ii hybrids were dwarf and compact in shape with high tillering ability and smaller spikes. Type III hybrids were similar to type I as a whole but had more compact and erect spikes. All the F-2 hybrid lines were superior to wheat in seed protein content, although some difference existed between themselves. Protein analysis of immature embryos and flag leaves from hybrids by two-dimensional electrophoresis showed that they possessed characteristic proteins of both parents and some new proteins. There existed also some different kinds of proteins in different lines.展开更多
Fe (iron) deficiency is an important nutritional problem particularly in crop plants grown on calcareous soils. Phytosiderophore (PS) release has been suggested to be linked to the ability of graminaceous species and ...Fe (iron) deficiency is an important nutritional problem particularly in crop plants grown on calcareous soils. Phytosiderophore (PS) release has been suggested to be linked to the ability of graminaceous species and genotypes to overcome Fe_deficiency chlorosis. Thus, enhancing PS release is a critical step to improve Fe nutrition of plants grown on Fe stressed soils. The heterosis of PS release rate in common wheat was studied by analyzing PS release from roots of three hybrids and their four parents grown in Fe_deficiency nutrient solution under controlled environmental conditions. PS release rates were determined at two or three day intervals after onset of Fe_deficiency symptoms by the measurement of Fe mobilizing capacity of root exudates from freshly precipitated FeⅢ hydroxide. High amounts of phytosiderophores were released from the roots of all wheat genotypes under Fe_deficiency, and the amount progressively increased with the development of Fe_deficiency chlorosis. The results revealed that the hybrids had more sensitive feedback systems which secreted more phytosiderophores under Fe_deficiency than their parents. By analyzing the relationship between each hybrid and its parents, it was also found that the parents should be selected on the basis of the rate of PS release and the combining ability by using the heterosis to improve Fe utilizability of crop plants.展开更多
[Objective] The effects of yttrium nitrate （YNO3） on biomass and antioxi- dant systems of paddy rice （Yttrium （Y）; Oxidative stress; Dismutases （SOD）; Per- oxidases （POD）, Catalases （CAT）, Paddy rice （Trit...[Objective] The effects of yttrium nitrate （YNO3） on biomass and antioxi- dant systems of paddy rice （Yttrium （Y）; Oxidative stress; Dismutases （SOD）; Per- oxidases （POD）, Catalases （CAT）, Paddy rice （Triticum aestivum）） together with the occurrences of Y in soils were investigated to assess its ecotoxicological effects on plant. [Method]Y solutions with various concentrations were sprinkled on soil sam- ples, which were well mixed and then put into culture dishes to culture paddy rice seeds for further evaluation. [Result] The results indicated that 25-100 mg/kg Y treatments significantly increased the biomass （total weight, root weight, shoot weight and leaf weight）, chlorophyll （CHL） content and protein content of paddy rice, whereas 200-800 mg/kg Y treatments had a converse effect. Similarly, biomarker for the antioxidant systems including superoxide dismutases （SOD）, peroxidases （POD） and catalases （CAT） all exhibited similar trends in both shoots and roots of paddy rice. At the same time, the malonaldehyde （MDA） content increased at from 25 to 100 mg/kg and decreased with concentrations of Y from 100 to 800 mg/kg in both shoots and roots of paddy rice. This indicated that Y could stimulate the growth of plant at low concentration, but inhibit the growth at relatively high concen- tration. [Conclusion] The levels of Y were 641＋49, 328_＋16 and 473_＋40 mg/kg in soils collected from mining area, farmland and navel orange orchard respectively. The levels of Y in the investigated area were higher than the benefit level （100 mg/kg）, which could cause low biomass as well as low activity of SOD, POD and CAT in paddy rice. Therefore, a more careful use of Y is necessary in crop management.展开更多
[Objective] The present study was conducted to provide basis for researches on breeding new wheat varieties and conserving rare species in Yunnan Province.[Method] 29 materials of Triticum aestivum ssp.yunnanense King...[Objective] The present study was conducted to provide basis for researches on breeding new wheat varieties and conserving rare species in Yunnan Province.[Method] 29 materials of Triticum aestivum ssp.yunnanense King（Yunnan Hulled Wheat）were taken for the research on classification and genetic diversity analysis based on 14 agronomic traits.[Result] Yunnan hulled wheat A14 could be an unnamed white seed variety,and other 28 materials were divided into 10 named mutation types;Yunnan hulled wheat was rich in variability of agronomic traits,in which the coefficient of variance（CV）of sterile spikelet number was the largest（22.59%）,while the CV of earing period was the lowest（3.71%）;the diversity indexes of seven qualitative characters ranged from 1.55-2.04.Moreover,the 29 Yunnan hulled wheat could be divided into 3 clusters by the UPGMA analysis.However,Yunnan hulled wheat varieties originating from similar mutation types did not completely cluster together.The genetic relationship was relatively close among A13（YT-35）,A14（YT-36）and A21（YT-37）,but the faster genetic relationship was observed between them and other Yunnan hulled wheat varieties.[Conclusion] Yunnan hulled wheat had an extensive genetic diversity in agronomic traits.展开更多
Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through...Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.展开更多
Drought is a major constraint in many wheat( Triticum aestivum L.) production regions. Quantitative trait loci (QTLs) conditioning drought tolerance at stages of germination and seedling in wheat were identified in...Drought is a major constraint in many wheat( Triticum aestivum L.) production regions. Quantitative trait loci (QTLs) conditioning drought tolerance at stages of germination and seedling in wheat were identified in a double haploid (DH) population derived from the cross, Hanxuan10×Lumai14, using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. Interval mapping analysis revealed that QTLs for drought tolerance at germination stage were located on chromosomes 1B, 2B, 5A, 6B, 7A and 7B, respectively, and the most effective QTL was mapped on chromosome 2B, explaining 27.2% of phenotypic variance. The QTLs for drought tolerance at seedling stage were located on 1B, 3B and 7B, respectively, and the most effective QTL was mapped on chromosome 3B, explaining 21.6% of phenotypic variance. Their positions were different from those of QTLs conferring drought tolerance at germination stage, indicating that drought tolerance at germination stage and seedling stage was controlled by different loci. Most of the identified QTLs explained 18% or more of phenotypic variance for drought tolerance at germination and seedling stage, and would be useful in future for marker assisted selection programs and cultivar improvement.展开更多
Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen applica...Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen application rates on wheat(Triticum aestivum L.) rhizosphere soil microorganisms and enzyme activities, and their temporal variations in relation to soil fertility under supplemental irrigation conditions in a fluvo-aquic region. For this, we established a split-plot experiment for two consecutive years(2014–2015 and 2015–2016) in the field with three levels of soil moisture: water deficit to no irrigation(W1), medium irrigation to(70±5)% of soil relative moisture after jointing stage(W2), and adequate irrigation to(80±5)% of soil relative moisture after jointing stage(W3);and three levels of nitrogen: 0 kg ha^–1(N1), 195 kg ha^–1(N2) and 270 kg ha^–1(N3). Results showed that irrigation and nitrogen application significantly increased rhizosphere microorganisms and enzyme activities. Soil microbiological properties showed different trends in response to N level;the highest values of bacteria, protease, catalase and phosphatase appeared in N2, while the highest levels of actinobacteria, fungi and urease were observed in N3. In addition, these items performed best under medium irrigation(W2) relative to W1 and W3;particularly the maximum microorganism(bacteria, actinobacteria and fungi) amounts appeared at W2, 5.37×10^7 and 6.35×10^7 CFUs g^–1 higher than those at W3 in 2014–2015 and 2015–2016, respectively;and these changes were similar in both growing seasons. Microbe-related parameters fluctuated over time but their seasonality did not hamper the irrigation and fertilization-induced effects. Further, the highest grain yields of 13 309.2 and 12 885.7 kg ha^–1 were both obtained at W2 N2 in 2014–2015 and 2015–2016, respectively. The selected properties, soil microorganisms and enzymes, were significantly correlated with wheat yield and proved to be valuable indicators of soil quality. These results clearly demonstrated that the combined treatment(W2 N2) significantly improved soil microbiological properties, soil fertility and wheat yield on the Huanghuai Plain, China.展开更多
In this study, 14 wheat cultivars with contrasting yield and N use efficiency （NUE） were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and hi...In this study, 14 wheat cultivars with contrasting yield and N use efficiency （NUE） were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and high N conditions. Under deficient-N, the cultivars with high N uptake efficiency （UpE） and high N utilization efficiency （UtE） exhibited higher plant biomass, yields, and N contents than those with medium and low NUEs. The high UpE cultivars accumulated more N than other NUE type cultivars. Under sufficient-N, the tested cultivars showed similar patterns in biomass, yield, and N content to those under deficient-N, but the varietal variations in above traits were smaller. In addition, the high UpE cultivars displayed much more of root biomass and larger of root length, surface area, and volume than other NUE type cultivars, indicating that the root morphological traits under N deprivation are closely associated with the plant biomass through its improvement of the N acquisition. The high UtE cultivars showed higher activities of nitrate reductase （NR）, nitrite reductase （NIR）, and gluta- mine synthetase （GS） at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high UpE and UtE cultivars also displayed higher photosynthetic rate under deficient-N than the medium and low NUE cultivars. Together, our results indicated that the tested wheat cultivars possess dramatically genetic variations in biomass, yield, and NUE. The root morphological traits and the N assimilation enzymatic acitivities play critical roles in regulating N accumulation and internal N translocation under the N-starvation stress, respectively. They can be used as morphological and biochemical references for evaluation of UpE and UtE in wheat.展开更多
Through regulating target genes via the mechanisms of posttranscriptional cleavage or translational repression, plant miRNAs involve diverse biological processes associating with plant growth, development, and abiotic...Through regulating target genes via the mechanisms of posttranscriptional cleavage or translational repression, plant miRNAs involve diverse biological processes associating with plant growth, development, and abiotic stress responses, in this study, we functionally characterized TaMIR1119, a miRNA family member of wheat （Triticum aestivum）, in regulating the drought adaptive response of plants. TaMIR1119 putatively targets six genes categorized into the functional classes of transcriptional regulation, RNA and biochemical metabolism, trafficking, and oxidative stress defense. Upon simulated drought stress, the TaMIR1119 transcripts abundance in roots was drastically altered, showing to be upregulated gradually within a 48-h drought regime andthat the drought-induced transcripts were gradually restored along with a 48-h recovery treatment. In contrast, most miRNA target genes displayed reverse expression patterns to TaMIR1119, exhibiting a downregulated expression pattern upon drought and whose reduced transcripts were re-elevated along with a normal recovery treatment. These expression analysis results indicated that TaMIR1119 responds to drought and regulates the target genes mainly through a cleavage mechanism. Under drought stress, the tobacco lines with TaMIR1119 overexpression behaved improved phenotypes,, showing increased plant biomass, photosynthetic parameters, osmolyte accumulation, and enhanced antioxidant enzyme （AE） activities relative to wild type. Three AE genes, NtFeSOD, NtCAT1;3, and NtSOD2,1, encoding superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） proteins, respectively, showed upregulated expression in TaMIR1119 overexpression lines, suggesting that they are involved in the regulation of AE activities and contribution to the improved cellular reactive oxygen species （ROS） homeostasis in drought-challenged transgenic lines. Our results indicate that TaMIR1119 plays critical roles in regulating plant drought tolerance through transcriptionally regulating the target genes that modulate osmolyte accumulation, photosynthetic function, and improve cellular ROS homeostasis of plants.展开更多
The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cul...The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cultivars of wheat （Triticum aestivum L.） exposed to 4℃. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4℃. The final leaf number （FLN） was determined throughout the vernalization periods （0, 7, 14, 24, and 35 d） at 4℃. The final leaf number decreased until days 24 and 35 in Sardari and Norstar eultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4℃-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4℃, the winter cultivars tended to produce more HMW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature （LT） tolerance proteins and determines the duration of expression of LT- induced proteins.展开更多
基金This research was funded and supported by the National Natural Science Foundation of China(Grant Number 32001443)Zhengzhou Major Science and Technology Innovation Project of Henan Province of China(Grant Number 2020CXZX0085)Science and Technology Inovation Team of Henan Academy of Agricultural Sciences(Grant Number 2024TD2).
文摘Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.
文摘mtDNAs of T type wheat cytoplasmic male sterile lines Ning Drawf 14(ND14) and their maintainers Ning Drawf 13 (ND13) were isolated and digested completely with restriction endonucleases EcoRI, PstI, EcoRV, BamHI. The results revealed that the molecular structure of mtDNAs from ND14 and ND13 cytoplasms were significantly deviated. The mitochondrial genomic difference between CMS line and maintainers were uncovered by southern hybridization with probes of 18S+5S rRNA、atpA genes from wheat and pea mitochondria, respectively. Due to the complexity of mtDNA and no proof of protein difference, it has not yet been demonstrated whether mtDNA difference of Normal and Male Sterile Cytoplasm of wheat is associated with CMS.
基金Supported by the National Natural Science Foundation of China(10475041)the Foundation of Nanjing Xiaozhuang University for the Key Discipline Construction(2005NXY01)the Scientific Research Founda-tion for Talents of Nanjing Xiaozhuang University(2008NXY04)~~
文摘[Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line,the analysis methods such as chromosome C-banding,genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS)was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS.
文摘Protoplasts derived from common wheat (Triticum aestivum L,. cv. Jinan 177) were fused with UV-treated protoplasts of Agropyron elongatum. (Host) Nevski by PEG method, and fertile asymmetric somatic hybrid plants resembling wheat morphology were obtained. The F-2 hybrid plants could be divided into 3 types according to their morphology. Type I hybrids had high and loosely standing stalks with big spikes and grains. Type ii hybrids were dwarf and compact in shape with high tillering ability and smaller spikes. Type III hybrids were similar to type I as a whole but had more compact and erect spikes. All the F-2 hybrid lines were superior to wheat in seed protein content, although some difference existed between themselves. Protein analysis of immature embryos and flag leaves from hybrids by two-dimensional electrophoresis showed that they possessed characteristic proteins of both parents and some new proteins. There existed also some different kinds of proteins in different lines.
文摘Fe (iron) deficiency is an important nutritional problem particularly in crop plants grown on calcareous soils. Phytosiderophore (PS) release has been suggested to be linked to the ability of graminaceous species and genotypes to overcome Fe_deficiency chlorosis. Thus, enhancing PS release is a critical step to improve Fe nutrition of plants grown on Fe stressed soils. The heterosis of PS release rate in common wheat was studied by analyzing PS release from roots of three hybrids and their four parents grown in Fe_deficiency nutrient solution under controlled environmental conditions. PS release rates were determined at two or three day intervals after onset of Fe_deficiency symptoms by the measurement of Fe mobilizing capacity of root exudates from freshly precipitated FeⅢ hydroxide. High amounts of phytosiderophores were released from the roots of all wheat genotypes under Fe_deficiency, and the amount progressively increased with the development of Fe_deficiency chlorosis. The results revealed that the hybrids had more sensitive feedback systems which secreted more phytosiderophores under Fe_deficiency than their parents. By analyzing the relationship between each hybrid and its parents, it was also found that the parents should be selected on the basis of the rate of PS release and the combining ability by using the heterosis to improve Fe utilizability of crop plants.
基金Supported by the National Natural Science Foundation of China(21067003,51364015)the National High-Tech Research and Development Program of China(2012BAC11B07)the Jiangxi Natural Science Foundation(20114BAB203024)~~
文摘[Objective] The effects of yttrium nitrate （YNO3） on biomass and antioxi- dant systems of paddy rice （Yttrium （Y）; Oxidative stress; Dismutases （SOD）; Per- oxidases （POD）, Catalases （CAT）, Paddy rice （Triticum aestivum）） together with the occurrences of Y in soils were investigated to assess its ecotoxicological effects on plant. [Method]Y solutions with various concentrations were sprinkled on soil sam- ples, which were well mixed and then put into culture dishes to culture paddy rice seeds for further evaluation. [Result] The results indicated that 25-100 mg/kg Y treatments significantly increased the biomass （total weight, root weight, shoot weight and leaf weight）, chlorophyll （CHL） content and protein content of paddy rice, whereas 200-800 mg/kg Y treatments had a converse effect. Similarly, biomarker for the antioxidant systems including superoxide dismutases （SOD）, peroxidases （POD） and catalases （CAT） all exhibited similar trends in both shoots and roots of paddy rice. At the same time, the malonaldehyde （MDA） content increased at from 25 to 100 mg/kg and decreased with concentrations of Y from 100 to 800 mg/kg in both shoots and roots of paddy rice. This indicated that Y could stimulate the growth of plant at low concentration, but inhibit the growth at relatively high concen- tration. [Conclusion] The levels of Y were 641＋49, 328_＋16 and 473_＋40 mg/kg in soils collected from mining area, farmland and navel orange orchard respectively. The levels of Y in the investigated area were higher than the benefit level （100 mg/kg）, which could cause low biomass as well as low activity of SOD, POD and CAT in paddy rice. Therefore, a more careful use of Y is necessary in crop management.
基金Supported by the Key Programs of Yunnan Province(2008CD010)the National Natural Science Foundation of China(30760119)Yunnan Provincial Science and Technology of Wheat UQECProgram(2010BB005)~~
文摘[Objective] The present study was conducted to provide basis for researches on breeding new wheat varieties and conserving rare species in Yunnan Province.[Method] 29 materials of Triticum aestivum ssp.yunnanense King（Yunnan Hulled Wheat）were taken for the research on classification and genetic diversity analysis based on 14 agronomic traits.[Result] Yunnan hulled wheat A14 could be an unnamed white seed variety,and other 28 materials were divided into 10 named mutation types;Yunnan hulled wheat was rich in variability of agronomic traits,in which the coefficient of variance（CV）of sterile spikelet number was the largest（22.59%）,while the CV of earing period was the lowest（3.71%）;the diversity indexes of seven qualitative characters ranged from 1.55-2.04.Moreover,the 29 Yunnan hulled wheat could be divided into 3 clusters by the UPGMA analysis.However,Yunnan hulled wheat varieties originating from similar mutation types did not completely cluster together.The genetic relationship was relatively close among A13（YT-35）,A14（YT-36）and A21（YT-37）,but the faster genetic relationship was observed between them and other Yunnan hulled wheat varieties.[Conclusion] Yunnan hulled wheat had an extensive genetic diversity in agronomic traits.
基金supported by the National Natural Science Foundation of China (30971773)the Natural Science Foundation of Hebei Province,China (C2011204031)the Key Laboratory of Crop Growth Regulation of Hebei Province,China
文摘Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.
文摘Drought is a major constraint in many wheat( Triticum aestivum L.) production regions. Quantitative trait loci (QTLs) conditioning drought tolerance at stages of germination and seedling in wheat were identified in a double haploid (DH) population derived from the cross, Hanxuan10×Lumai14, using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers. Interval mapping analysis revealed that QTLs for drought tolerance at germination stage were located on chromosomes 1B, 2B, 5A, 6B, 7A and 7B, respectively, and the most effective QTL was mapped on chromosome 2B, explaining 27.2% of phenotypic variance. The QTLs for drought tolerance at seedling stage were located on 1B, 3B and 7B, respectively, and the most effective QTL was mapped on chromosome 3B, explaining 21.6% of phenotypic variance. Their positions were different from those of QTLs conferring drought tolerance at germination stage, indicating that drought tolerance at germination stage and seedling stage was controlled by different loci. Most of the identified QTLs explained 18% or more of phenotypic variance for drought tolerance at germination and seedling stage, and would be useful in future for marker assisted selection programs and cultivar improvement.
基金supported by the National Technology R&D Program of China (2013BAD07B07, 2015BAD26B01 and 2018YFD0300701)
文摘Soil management practices affect rhizosphere microorganisms and enzyme activities, which in turn influence soil ecosystem processes. The objective of this study was to explore the effects of different nitrogen application rates on wheat(Triticum aestivum L.) rhizosphere soil microorganisms and enzyme activities, and their temporal variations in relation to soil fertility under supplemental irrigation conditions in a fluvo-aquic region. For this, we established a split-plot experiment for two consecutive years(2014–2015 and 2015–2016) in the field with three levels of soil moisture: water deficit to no irrigation(W1), medium irrigation to(70±5)% of soil relative moisture after jointing stage(W2), and adequate irrigation to(80±5)% of soil relative moisture after jointing stage(W3);and three levels of nitrogen: 0 kg ha^–1(N1), 195 kg ha^–1(N2) and 270 kg ha^–1(N3). Results showed that irrigation and nitrogen application significantly increased rhizosphere microorganisms and enzyme activities. Soil microbiological properties showed different trends in response to N level;the highest values of bacteria, protease, catalase and phosphatase appeared in N2, while the highest levels of actinobacteria, fungi and urease were observed in N3. In addition, these items performed best under medium irrigation(W2) relative to W1 and W3;particularly the maximum microorganism(bacteria, actinobacteria and fungi) amounts appeared at W2, 5.37×10^7 and 6.35×10^7 CFUs g^–1 higher than those at W3 in 2014–2015 and 2015–2016, respectively;and these changes were similar in both growing seasons. Microbe-related parameters fluctuated over time but their seasonality did not hamper the irrigation and fertilization-induced effects. Further, the highest grain yields of 13 309.2 and 12 885.7 kg ha^–1 were both obtained at W2 N2 in 2014–2015 and 2015–2016, respectively. The selected properties, soil microorganisms and enzymes, were significantly correlated with wheat yield and proved to be valuable indicators of soil quality. These results clearly demonstrated that the combined treatment(W2 N2) significantly improved soil microbiological properties, soil fertility and wheat yield on the Huanghuai Plain, China.
基金supported by the Chinese National Programs of Science and Technology for High Yielding Crop Production (2011BAD16B08, 2012BAD04B06, and 2013BAD07B05)the Key Laboratory of Crop Growth Regulation of Hebei Province, China
文摘In this study, 14 wheat cultivars with contrasting yield and N use efficiency （NUE） were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and high N conditions. Under deficient-N, the cultivars with high N uptake efficiency （UpE） and high N utilization efficiency （UtE） exhibited higher plant biomass, yields, and N contents than those with medium and low NUEs. The high UpE cultivars accumulated more N than other NUE type cultivars. Under sufficient-N, the tested cultivars showed similar patterns in biomass, yield, and N content to those under deficient-N, but the varietal variations in above traits were smaller. In addition, the high UpE cultivars displayed much more of root biomass and larger of root length, surface area, and volume than other NUE type cultivars, indicating that the root morphological traits under N deprivation are closely associated with the plant biomass through its improvement of the N acquisition. The high UtE cultivars showed higher activities of nitrate reductase （NR）, nitrite reductase （NIR）, and gluta- mine synthetase （GS） at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high UpE and UtE cultivars also displayed higher photosynthetic rate under deficient-N than the medium and low NUE cultivars. Together, our results indicated that the tested wheat cultivars possess dramatically genetic variations in biomass, yield, and NUE. The root morphological traits and the N assimilation enzymatic acitivities play critical roles in regulating N accumulation and internal N translocation under the N-starvation stress, respectively. They can be used as morphological and biochemical references for evaluation of UpE and UtE in wheat.
基金supported by the National Natural Science Foundation of China (31371618)the Research Plan of Application Base of Hebei, China (17962901D)
文摘Through regulating target genes via the mechanisms of posttranscriptional cleavage or translational repression, plant miRNAs involve diverse biological processes associating with plant growth, development, and abiotic stress responses, in this study, we functionally characterized TaMIR1119, a miRNA family member of wheat （Triticum aestivum）, in regulating the drought adaptive response of plants. TaMIR1119 putatively targets six genes categorized into the functional classes of transcriptional regulation, RNA and biochemical metabolism, trafficking, and oxidative stress defense. Upon simulated drought stress, the TaMIR1119 transcripts abundance in roots was drastically altered, showing to be upregulated gradually within a 48-h drought regime andthat the drought-induced transcripts were gradually restored along with a 48-h recovery treatment. In contrast, most miRNA target genes displayed reverse expression patterns to TaMIR1119, exhibiting a downregulated expression pattern upon drought and whose reduced transcripts were re-elevated along with a normal recovery treatment. These expression analysis results indicated that TaMIR1119 responds to drought and regulates the target genes mainly through a cleavage mechanism. Under drought stress, the tobacco lines with TaMIR1119 overexpression behaved improved phenotypes,, showing increased plant biomass, photosynthetic parameters, osmolyte accumulation, and enhanced antioxidant enzyme （AE） activities relative to wild type. Three AE genes, NtFeSOD, NtCAT1;3, and NtSOD2,1, encoding superoxide dismutase （SOD）, catalase （CAT）, and peroxidase （POD） proteins, respectively, showed upregulated expression in TaMIR1119 overexpression lines, suggesting that they are involved in the regulation of AE activities and contribution to the improved cellular reactive oxygen species （ROS） homeostasis in drought-challenged transgenic lines. Our results indicate that TaMIR1119 plays critical roles in regulating plant drought tolerance through transcriptionally regulating the target genes that modulate osmolyte accumulation, photosynthetic function, and improve cellular ROS homeostasis of plants.
基金financially supported by a grant from Tarbiat Modares University,Tehran,Iran
文摘The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cultivars of wheat （Triticum aestivum L.） exposed to 4℃. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4℃. The final leaf number （FLN） was determined throughout the vernalization periods （0, 7, 14, 24, and 35 d） at 4℃. The final leaf number decreased until days 24 and 35 in Sardari and Norstar eultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4℃-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4℃, the winter cultivars tended to produce more HMW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature （LT） tolerance proteins and determines the duration of expression of LT- induced proteins.
