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 ...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
Allelic variation in two domestic wheat landraces, Pingyaobaimai and Mazhamai, two cornerstone breeding materials and their derived cultivars with drought tolerance was detected by SSR (simple sequence repeat) markers...Allelic variation in two domestic wheat landraces, Pingyaobaimai and Mazhamai, two cornerstone breeding materials and their derived cultivars with drought tolerance was detected by SSR (simple sequence repeat) markers. The clustering of 25 accessions showed that the similarity between Pingyaobaimai and Yanda1817, the latter was developed from the former, was 0.71, the highest one of all accessions, but the similarities were very low between these two accessions and other accessions including their derived cultivars. A similar situation was revealed between Mazhamai and its derived cultivars. Pingyaobaimai and its three derived cultivars shared three alleles at loci Xgwm526, Xgwm538 and Xgwm126 on chromosome arms 2BL, 4BL and 5AL, respectively. There were six shared alleles in Mazhamai and its derived cultivars, in order of Xgwm157,Xgwm126, Xgwm212, Xgwm626, Xgwm471 and Xgwm44 on chromosome arms 2DL, 5AL, 5DL, 6BL, 7AS and 7DC, respectively. Only one shared allele was detected between the pedigrees of Pingyaobaimai and Mazhamai. The difference of shared alleles in two cornerstone breeding materials and their derived cultivars revealed the diversity in Chinese wheat germplasm with drought tolerance and the complication in genetic basis of drought tolerance in wheat.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
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 and that 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
Heading date was an important trait that decided the adaptation of wheat to environments.It was modified by genes involved in vernalization response,photoperiod response and development rate.In this study,four loci Xg...Heading date was an important trait that decided the adaptation of wheat to environments.It was modified by genes involved in vernalization response,photoperiod response and development rate.In this study,four loci Xgwm261,Xgwm219,Xbarc23and Ppd-D1 which were previously reported related to heading time were analyzed based on three groups of wheat including landraces(L),varieties bred before 1983(B82)and after 1983(A83)collected from Chinese wheat growing areas.Generally,heading date of landrace was longer than that of varieties.Significant differences in the heading time existed within the groups,which implied that diversification selection was much helpful for adaptation in each wheat zone.Photoperiod insensitive allele Ppd-D1a was the first choice for both landrace and modern varieties,which promoted the heading date about four days earlier than that of sensitive allele Ppd-D1b.The three SSR loci had different characters in the three groups.Predominant allele combination for each zone was predicted for wheat group L and A83,which made great contribution to advantageous traits.Xgwm219 was found to be significantly associated with heading date in Yellow and Huai River Winter Wheat Zone(Zone II)and spike length in Middle and lower Yangtze Valley Winter Wheat Zone(Zone III),which implied functional diversification for adaption.Variation for earliness genes provided here will be helpful for whet breeding in future climatic change.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) cultivars o...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°C.Plants were sampled on days 2,14,21 and 35 of exposure to 4°C.The final leaf number(FLN) was determined throughout the vernalization periods(0,7,14,24,and 35 d) at 4°C.The final leaf number decreased until days 24 and 35 in Sardari and Norstar cultivars,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°C-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°C,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
Stomatal density and size affect plant water use efficiency, photosynthsis rate and yield. The objective of this study was to gain insights into the variation and genetic basis of stomatal density and size during grai...Stomatal density and size affect plant water use efficiency, photosynthsis rate and yield. The objective of this study was to gain insights into the variation and genetic basis of stomatal density and size during grain filling under drought stress(DS) and well-watered(WW) conditions. The doubled haploid population derived from a cross of wheat cultivars Hanxuan 10(H10), a female parent, and Lumai 14(L14), a male parent, was used for phenotyping at the heading, flowering, and mid- and late grain filling stages along with established amplified fragment length polymorphism(AFLP) and simple sequence repeat(SSR) markers. The stomatal density of doubled haploid(DH) lines was gradually increased, while the stomatal lengths and widths were gradually decreased during grain filling stage. Twenty additive QTLs and 19 pairs of epistatic QTLs for the 3 traits were identified under DS. The other 20 QTLs and 25 pairs epistatic QTLs were obtained under WW. Most QTLs made more than 10% contributions to the total phenotypic variations at one growth stage under DS or WW. Furthermore, QTLs for stomatal density near Xwmc74 and Xgwm291 located on chromosome 5A were tightly linked to previously reported QTLs regulating total number of spikelets per spike, number of sterile spikelets per spike and proportion of fertile spikelets per spike. Qsw-2D-1 was detected across stages, and was in the same marker region as a major QTL for plant height, QPH.cgb-2D.1. These indicate that these QTLs on chromosomes 5A and 2D are involved in regulating these agronomic traits and are valuable for molecular breeding.展开更多
MADS-box(MADS) transcription factors(TFs) act as one of the largest TF families in plants.The members in this family play fundamental roles in almost every developmental process as well as involve plant responses to b...MADS-box(MADS) transcription factors(TFs) act as one of the largest TF families in plants.The members in this family play fundamental roles in almost every developmental process as well as involve plant responses to biotic and abiotic stresses.In this study,54 of MADS genes in wheat,including 31 released publicly and 23 deposited as tentative consensus(TC)into GenBank database,were subjected to analyses of molecular characterization,expression pattern,and function under contrasting phosphate(Pi)-supply conditions.The 31 released MADS genes share cDNA full lengths of 683 to 1 297 bp,encoding amino acids of 170 to 274 aa that possess molecular weights of 19.21 to 31.33 kDa and isoelectric points of5.74 to 9.63.Phylogenetic analysis categoried these wheat MADS genes into four subgroups containing 11,5,10,and 4members,respectively.Under Pi sufficiency,the MADS genes showed drastically varied transcripts and they were categoried into expression groups of high,medium,low,and very low,respectively.Among them,several ones were differentially expressed under Pi deprivation,including that five were upregulated(TaMADS51,TaMADS4,TaMADS5,TaMADS6,and TaMADS18) and four were downregulated(TaMADAGLU,TaMADAGL2,TaMADWM31 C,and TaMADS;14).qPCR analyses confirmed their expression patterns in responding to the Pi-starvation stress.TaMADS51,one of the upregulated genes by Pi deprivation,was subjected to the functional analysis in mediating plant tolerance to the Pi-starvation stress.The transgenic tobocco plants overexpressing TaMADS51 exhibited much more improved growth features,drymass,Pi acquisition,and photosynthetic parameters as well as antioxidant enzymatic activities under Pi deprivation than wild type.These results indicate that distinct MADS genes are transcriptional response to Pi deprivation and play critical roles in mediating plant tolerance to this stressor through regulating downstream Pi-responsive genes.展开更多
Field trials with a set of 108 doubled haploid lines(DHs) derived from a cross between the Chinese winter wheat cvs.CA9613 and H1488 were run at Beijing(China).Phenotypic data were recorded for major agronomic yield t...Field trials with a set of 108 doubled haploid lines(DHs) derived from a cross between the Chinese winter wheat cvs.CA9613 and H1488 were run at Beijing(China).Phenotypic data were recorded for major agronomic yield traits,i.e.grain weight per ear,grain number per ear and thousand grain weight(Tgw) in two field trials at Beijing.Based on the phenotypic data and a genetic map comprising 168 SSR markers,an analysis of quantitative trait loci(QTL) was carried out for yield and yield parameters using the composite interval mapping(CIM) approach.A total of 14 QTL were detected for these traits across two environments.Four of these QTL located on chromosomes 1A and 2B,respectively,exhibited pleiotropic effects.Loci showing pleiotropic effects will be very useful for understanding the homeologous relationships of QTL and designing an appropriate marker-assisted selection programme by multi-trait selection in order to accumulate("pyramide") favorable alleles at different loci.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 high ...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 Up E 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 Up E 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 Ut E cultivars showed higher activities of nitrate reductase(NR), nitrite reductase(NIR), and glutamine synthetase(GS) at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high Up E and Ut E 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 Up E and Ut E in wheat.展开更多
The effects of auxins and media on callus induction from the mature and immature embryos of Chinese spring wheat (Triticum aestivum L.) varieties were investigated. It was found that genotype, medium, auxin source and...The effects of auxins and media on callus induction from the mature and immature embryos of Chinese spring wheat (Triticum aestivum L.) varieties were investigated. It was found that genotype, medium, auxin source and concentration had the significant effects on the induction of embryogenic callus, explants germination and the increment of callus fresh weight. For immature embryos cultured on MS medium, 2 mg L-1of 2, 4-D was optimal, and the highest frequency of embryogenic callus (33.50%) was observed. For the mature embryos on N6 medium, 4 mg L-1 of 2, 4-D was optimal. The frequency of embryogenic callus and increment of callus fresh weight on 2, 4, 5-T media were higher than those on 2, 4-D media, and in the presence of 2, 4, 5-T the precocious germination of explants for all genotypes were significantly suppressed. These results indicated that 2, 4, 5-T was superior to 2, 4-D and NAA in the culture of immature embryos. This is the first report about the effect of 2, 4, 5-T and NAA on wheat tissue culture, particularly in comparison with 2, 4-D in detail.展开更多
Dissecting the genetic relationships among gluten-related traits is important for high quality wheat breeding. Quantitative trait loci(QTLs) analysis for gluten strength,as measured by sedimentation volume(SV) and glu...Dissecting the genetic relationships among gluten-related traits is important for high quality wheat breeding. Quantitative trait loci(QTLs) analysis for gluten strength,as measured by sedimentation volume(SV) and gluten index(GI),was performed using the QTLNetwork 2.0 software. Recombinant inbred lines(RILs) derived from the winter wheat varieties Shannong 01-35×Gaocheng 9411 were used for the study. A total of seven additive QTLs for gluten strength were identified using an unconditional analysis. QGi1 D-13 and QSv1 D-14 were detected through unconditional and conditional QTLs mapping,which explained 9.15–45.08% of the phenotypic variation. QTLs only identified under conditional QTL mapping were located in three marker intervals:WPT-3743–GLU-D1(1 D),WPT-7001–WMC258(1 B),and WPT-8682–WPT-5562(1 B). Six pairs of epistatic QTLs distributed nine chromosomes were identified. Of these,two main effect QTLs(QGi1 D-13 and QSv1 D-14) and 12 pairs of epistatic QTLs were involved in interactions with the environment. The results indicated that chromosomes 1 B and 1 D are important for the improvement of gluten strength in common wheat. The combination of conditional and unconditional QTLs mapping could be useful for a better understanding of the interdependence of different traits at the QTL molecular level.展开更多
Zinc finger protein(ZFP) genes comprise a large and diverse gene family, and are involved in biotic and abiotic stress responses in plants. In this study, a total of 126 ZFP genes classified into various types in whea...Zinc finger protein(ZFP) genes comprise a large and diverse gene family, and are involved in biotic and abiotic stress responses in plants. In this study, a total of 126 ZFP genes classified into various types in wheat were characterized and subjected to expression pattern analysis under inorganic phosphate(Pi) deprivation. The wheat ZFP genes and their corresponding GenBank numbers were obtained from the information of a 4×44K wheat gene expression microarray chip. They were confirmed by sequence similarity analysis and named based on their homologs in Brachypodium distachyon or Oriza sativa. Expression analysis based on the microarray chip revealed that these ZFP genes are categorized into 11 classes according to their gene expression patterns in a 24-h of Pi deprivation regime. Among them, ten genes were differentially up-regulated, ten genes differentially downregulated, and two genes both differentially up- and down-regulated by Pi deprivation. The differentially up- or down-regulated genes exhibited significantly more or less transcripts at one, two, or all of the checking time points(1, 6, and 24 h) of Pi stress in comparison with those of normal growth, respectively. The both differentially up- and down-regulated genes exhibited contrasting expression patterns, of these, TaWRKY70;5 showed significantly up-regulated at 1 and 6 h and down-regulated at 24 h whereas TaAN1AN20-8;2 displayed significantly upregulated at 1 h and downregulated at 6 h under deprivation Pi condition. Real time PCR analysis confirmed the expression patterns of the differentially expressed genes obtained by the microarray chip. Our results indicate that numerous ZFP genes in wheat respond to Pi deprivation and have provided further insight into the molecular basis that plants respond to Pi deprivation mediated by the ZFP gene family.展开更多
Mitogen-activated protein kinase(MPK) cascades consist of a set of kinase types(MPKKKs,MPKKs,MPKs) to establish conserved signal-transducing modules mediating plant growth,development as well as responses to internal ...Mitogen-activated protein kinase(MPK) cascades consist of a set of kinase types(MPKKKs,MPKKs,MPKs) to establish conserved signal-transducing modules mediating plant growth,development as well as responses to internal and external cues.In this study,the expression patterns of six MPKKK,two MPKK,and 11 MPK genes in wheat in responses to external treatments of phytohormones,including naphthylacetic acid(NAA),abscisic acid(ABA),6-benzyladenine(6-BA),gibberellin(GA_3),salisylic acid(SA),jasmonic acid(JA),and ethylene(ETH),were investigated.Expression analysis revealed that several of the MPK cascade genes are responses to the external phytohormone signaling.Of which,TaMPKKKA;3is induced by 6-BA and NAA while TaMPK4 repressed by ETH,GA_3,SA,and JA;TaMPKKKA,TaMPKKKA;3 and TaMPK1 are down-regulated by ETH and GA_3whereas TaMPK9 and TaMPK12 repressed by ETH and JA in addition that TaMPK12 also repressed by GA_3;TaMPK12;1 is down-regulated by ABA,GA_3 and SA while TaMPK17 repressed by all exogenous phytonormones examined.TaMPK4,a MPK type gene previously characterized to mediate tolerance to phosphate(Pi)deprivation,was functionally evaluated for its role in mediation of responses of plants to exogenous GA_3,ETH,SA,and JA.Results indicated that overexpression and antisense expression of TaMPK4 in tobacco dramatically modify the growth of seedlings upon treatments of GA_3,SA and JA,in which the overexpressors behaved deteriorated growth feature whereas the seedlings with antisense expression of TaMPK4 exhibited improved seedling phenotype.The growth behaviors in lines overexpressing or antisensely expressing TaMPK4 are closely associated with the biomass and the corresponding hormone-associated parameters.These results demonstrated that TaMPK4 acts as a critical player in mediating the phytohormone signaling.Our findings have identified the phytohormone-responsive MPK cascade genes in wheat and provided a connection between the phytohormone-mediated responses and the MPK cascade pathways.展开更多
Growth and physiological responses of wheat to sand burial were studied in Horqin Sandy Land, to determine the impact on productivity and survival as well as antioxidant enzymes responses. This study consisted of one ...Growth and physiological responses of wheat to sand burial were studied in Horqin Sandy Land, to determine the impact on productivity and survival as well as antioxidant enzymes responses. This study consisted of one control(no sand) and four sand burial treatments: 25%, 50%, 75% and 100% of seedling height, respectively. Minor burial(25%) had no effect on wheat growth and survival; deep burial(100%) was fatal, and the others had an intermediate effect. Thus, the survival limit to sand burial was equal to seedling height. Sand burial mainly decreased shoot biomass and crop yield, but had small effects on belowground biomass. Superoxide dismutase(SOD) activity increased with time after burial in all treatments with surviving plants. Peroxidase(POD) activity increased after six days under burial, and catalase(CAT) activity decreased after burial, but recovered after 12 days. The concentration of malondialdehyde(MDA), a marker for oxidative stress, was low on the sixth day, but increased thereafter with burial depth. Thus, sand burial >25% should be avoided due to growth rate reduction leading to reduced crop yield, and even 25% burial showed physiological indicators of stress.展开更多
<span style="font-family:Verdana;">A field trial was conducted at a private farm in AL-Hashimiya district Babylon Governorate—the republic of Iraq during the 2016</span><span style="font...<span style="font-family:Verdana;">A field trial was conducted at a private farm in AL-Hashimiya district Babylon Governorate—the republic of Iraq during the 2016</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2017 and 2017</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">2018 growing seasons.</span><span style="color:red;"> </span><span style="font-family:Verdana;">This study was conducted using two irrigation methods, sprinkler and surface irrigation, for each of them had three Tillage methods (zero-tillage</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> medium-tillage</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> deep-tillage) and each tillage system had four seeding rate of wheat yield (120</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">180</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">240</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">300) kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">Results indicated that the consumptive water use was 557.5 and</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">535.9 mm for surface irrigation and 460.9 and 442.6 mm for sprinkler irrigation in </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">2016-2017 and 2017-2018 growing seasons. Sprinkler irrigation significantly increased the flag leaf area with no significant effect on plant height. However, the minimum tillage and seeding rate (240 kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup></span><span style="font-family:;" "=""><span style="font-family:Verdana;">) significantly increased the plant height and flag leaf </span><span style="font-family:Verdana;">area in both growing seasons. For the grain yield, the sprinkler irrigation, m</span><span style="font-family:Verdana;">inimum tillage, and seeding rate (240 </span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup></span><span style="font-family:;" "=""><span style="font-family:Verdana;">) also increased the plant height and flag leaf area by 13%, 10, % 11%, 11%, 12%, and 14% in both growing seasons, respectively, through an increased number of spikes/m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, the number of grain spike-1, and 1000-grain weight in both growing seasons, respe</span></span><span style="font-family:Verdana;">ctively. Interestingly the grain yield was increased by 33% and 32% in both growing seasons under the effects of these three factors altogether, respectively. It can be concluded that these factors act synergistically, resulting in a significant improvement in the wheat grain-yield of, less consumptive water use, and high water use efficiency.</span>展开更多
Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant culti...Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant cultivars.In the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the greenhouse.These cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping seasons.Furthermore,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat genotypes.Results showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling stage.Nonetheless,Lr1 was detected only in Hongtangliangmai.The field experimental test of the two environments showed that 38 landraces showed slow rusting resistance.Seven cultivars possessed Lr34 but none of the landraces contained Lr37 and Lr46.Lr genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant stage.Lr18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant stage.Lr34 as a slowing rusting gene showed good resistance in the field.Four race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field experiments.Seven race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost resistance.The 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China.展开更多
Plant N starvation response is closely associated with the N signaling components that involve transduction of the low-N cues. In this study, we functionally characterized Ta ARR1, a cytokinin(CK) response regulator g...Plant N starvation response is closely associated with the N signaling components that involve transduction of the low-N cues. In this study, we functionally characterized Ta ARR1, a cytokinin(CK) response regulator gene in Triticum aestivum, in mediating the N starvation adaptation in plants. Ta ARR1 harbors two conserved domains specified by plant ARR family members;subcellular localization analysis indicated its target onto nucleus after endoplasmic reticulum assortment. Ta ARR1 displayed modified expression upon the N starvation stressor, showing upregulated expression in roots and leaves over a 27-h N starvation treatment and whose induced transcripts were gradually recovered along with progression of the N recovery treatment. The tobacco lines overexpressing Ta ARR1 displayed improved low-N stress tolerance, displaying enlarged phenotype, increased biomass and N accumulation, and enhanced glutamine synthetase(GS) activities compared with wild type(WT) following the N starvation treatment. Expression analysis on genes encoding the nitrate transporter(NRT) and GS proteins in Nicotiana tabacum revealed that Nt NRT2.2 and Nt GS3 are upregulated in expression in the N-deprived transgenic lines, whose expression patterns were contrasted to other above family genes that were unaltered on transcripts between the transgenic lines and WT. Transgene analysis validated the function of Nt NRT2.2 and Nt GS3 in regulating N accumulation, GS activity, growth traits, and N use efficiency in plants. These results suggested the internal connection between the Ta ARR1-mediated N starvation tolerance and the modified transcription of distinct N acquisitionand assimilation-associated genes. Our investigation together indicates that Ta ARR1 is essential in plant N starvation adaptation due to the gene function in transcriptionally regulating distinct NRT and GS genes that affect plant N uptake and assimilation under the N starvation condition.展开更多
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.
文摘Allelic variation in two domestic wheat landraces, Pingyaobaimai and Mazhamai, two cornerstone breeding materials and their derived cultivars with drought tolerance was detected by SSR (simple sequence repeat) markers. The clustering of 25 accessions showed that the similarity between Pingyaobaimai and Yanda1817, the latter was developed from the former, was 0.71, the highest one of all accessions, but the similarities were very low between these two accessions and other accessions including their derived cultivars. A similar situation was revealed between Mazhamai and its derived cultivars. Pingyaobaimai and its three derived cultivars shared three alleles at loci Xgwm526, Xgwm538 and Xgwm126 on chromosome arms 2BL, 4BL and 5AL, respectively. There were six shared alleles in Mazhamai and its derived cultivars, in order of Xgwm157,Xgwm126, Xgwm212, Xgwm626, Xgwm471 and Xgwm44 on chromosome arms 2DL, 5AL, 5DL, 6BL, 7AS and 7DC, respectively. Only one shared allele was detected between the pedigrees of Pingyaobaimai and Mazhamai. The difference of shared alleles in two cornerstone breeding materials and their derived cultivars revealed the diversity in Chinese wheat germplasm with drought tolerance and the complication in genetic basis of drought tolerance in wheat.
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 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 and that 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supported by the National Basic Research Program of China(2010CB951500)
文摘Heading date was an important trait that decided the adaptation of wheat to environments.It was modified by genes involved in vernalization response,photoperiod response and development rate.In this study,four loci Xgwm261,Xgwm219,Xbarc23and Ppd-D1 which were previously reported related to heading time were analyzed based on three groups of wheat including landraces(L),varieties bred before 1983(B82)and after 1983(A83)collected from Chinese wheat growing areas.Generally,heading date of landrace was longer than that of varieties.Significant differences in the heading time existed within the groups,which implied that diversification selection was much helpful for adaptation in each wheat zone.Photoperiod insensitive allele Ppd-D1a was the first choice for both landrace and modern varieties,which promoted the heading date about four days earlier than that of sensitive allele Ppd-D1b.The three SSR loci had different characters in the three groups.Predominant allele combination for each zone was predicted for wheat group L and A83,which made great contribution to advantageous traits.Xgwm219 was found to be significantly associated with heading date in Yellow and Huai River Winter Wheat Zone(Zone II)and spike length in Middle and lower Yangtze Valley Winter Wheat Zone(Zone III),which implied functional diversification for adaption.Variation for earliness genes provided here will be helpful for whet breeding in future climatic change.
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°C.Plants were sampled on days 2,14,21 and 35 of exposure to 4°C.The final leaf number(FLN) was determined throughout the vernalization periods(0,7,14,24,and 35 d) at 4°C.The final leaf number decreased until days 24 and 35 in Sardari and Norstar cultivars,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°C-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°C,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.
基金supported by the National Science and Technology Major Projects for Cultivation of New Transgenic Varieties,Ministry of Agriculture of China(2014ZX0800203B-003)the Natural Science Foundation of Shanxi Province,China(2014011004-3)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education,China(20121403110005)a Program of Consultative Group for International Agricultural Research(CGIAR)Project,Generation Challenge Programme(G7010.02.01)
文摘Stomatal density and size affect plant water use efficiency, photosynthsis rate and yield. The objective of this study was to gain insights into the variation and genetic basis of stomatal density and size during grain filling under drought stress(DS) and well-watered(WW) conditions. The doubled haploid population derived from a cross of wheat cultivars Hanxuan 10(H10), a female parent, and Lumai 14(L14), a male parent, was used for phenotyping at the heading, flowering, and mid- and late grain filling stages along with established amplified fragment length polymorphism(AFLP) and simple sequence repeat(SSR) markers. The stomatal density of doubled haploid(DH) lines was gradually increased, while the stomatal lengths and widths were gradually decreased during grain filling stage. Twenty additive QTLs and 19 pairs of epistatic QTLs for the 3 traits were identified under DS. The other 20 QTLs and 25 pairs epistatic QTLs were obtained under WW. Most QTLs made more than 10% contributions to the total phenotypic variations at one growth stage under DS or WW. Furthermore, QTLs for stomatal density near Xwmc74 and Xgwm291 located on chromosome 5A were tightly linked to previously reported QTLs regulating total number of spikelets per spike, number of sterile spikelets per spike and proportion of fertile spikelets per spike. Qsw-2D-1 was detected across stages, and was in the same marker region as a major QTL for plant height, QPH.cgb-2D.1. These indicate that these QTLs on chromosomes 5A and 2D are involved in regulating these agronomic traits and are valuable for molecular breeding.
基金supported by the National Natural Science Foundation of China (31201674 and 31371618)the National Transgenic Major Program, China (2011ZX08008)
文摘MADS-box(MADS) transcription factors(TFs) act as one of the largest TF families in plants.The members in this family play fundamental roles in almost every developmental process as well as involve plant responses to biotic and abiotic stresses.In this study,54 of MADS genes in wheat,including 31 released publicly and 23 deposited as tentative consensus(TC)into GenBank database,were subjected to analyses of molecular characterization,expression pattern,and function under contrasting phosphate(Pi)-supply conditions.The 31 released MADS genes share cDNA full lengths of 683 to 1 297 bp,encoding amino acids of 170 to 274 aa that possess molecular weights of 19.21 to 31.33 kDa and isoelectric points of5.74 to 9.63.Phylogenetic analysis categoried these wheat MADS genes into four subgroups containing 11,5,10,and 4members,respectively.Under Pi sufficiency,the MADS genes showed drastically varied transcripts and they were categoried into expression groups of high,medium,low,and very low,respectively.Among them,several ones were differentially expressed under Pi deprivation,including that five were upregulated(TaMADS51,TaMADS4,TaMADS5,TaMADS6,and TaMADS18) and four were downregulated(TaMADAGLU,TaMADAGL2,TaMADWM31 C,and TaMADS;14).qPCR analyses confirmed their expression patterns in responding to the Pi-starvation stress.TaMADS51,one of the upregulated genes by Pi deprivation,was subjected to the functional analysis in mediating plant tolerance to the Pi-starvation stress.The transgenic tobocco plants overexpressing TaMADS51 exhibited much more improved growth features,drymass,Pi acquisition,and photosynthetic parameters as well as antioxidant enzymatic activities under Pi deprivation than wild type.These results indicate that distinct MADS genes are transcriptional response to Pi deprivation and play critical roles in mediating plant tolerance to this stressor through regulating downstream Pi-responsive genes.
文摘Field trials with a set of 108 doubled haploid lines(DHs) derived from a cross between the Chinese winter wheat cvs.CA9613 and H1488 were run at Beijing(China).Phenotypic data were recorded for major agronomic yield traits,i.e.grain weight per ear,grain number per ear and thousand grain weight(Tgw) in two field trials at Beijing.Based on the phenotypic data and a genetic map comprising 168 SSR markers,an analysis of quantitative trait loci(QTL) was carried out for yield and yield parameters using the composite interval mapping(CIM) approach.A total of 14 QTL were detected for these traits across two environments.Four of these QTL located on chromosomes 1A and 2B,respectively,exhibited pleiotropic effects.Loci showing pleiotropic effects will be very useful for understanding the homeologous relationships of QTL and designing an appropriate marker-assisted selection programme by multi-trait selection in order to accumulate("pyramide") favorable alleles at different loci.
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 Up E 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 Up E 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 Ut E cultivars showed higher activities of nitrate reductase(NR), nitrite reductase(NIR), and glutamine synthetase(GS) at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high Up E and Ut E 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 Up E and Ut E in wheat.
基金the National High Tech R&D Program of China(863 Program,2003AA207100)the Foundation for the Author of National Excellent Doctoral Dissertation of P R China(200357) the Program forChangjiang Scholars and Innovative Research Team inUniversity(IRT0453).
文摘The effects of auxins and media on callus induction from the mature and immature embryos of Chinese spring wheat (Triticum aestivum L.) varieties were investigated. It was found that genotype, medium, auxin source and concentration had the significant effects on the induction of embryogenic callus, explants germination and the increment of callus fresh weight. For immature embryos cultured on MS medium, 2 mg L-1of 2, 4-D was optimal, and the highest frequency of embryogenic callus (33.50%) was observed. For the mature embryos on N6 medium, 4 mg L-1 of 2, 4-D was optimal. The frequency of embryogenic callus and increment of callus fresh weight on 2, 4, 5-T media were higher than those on 2, 4-D media, and in the presence of 2, 4, 5-T the precocious germination of explants for all genotypes were significantly suppressed. These results indicated that 2, 4, 5-T was superior to 2, 4-D and NAA in the culture of immature embryos. This is the first report about the effect of 2, 4, 5-T and NAA on wheat tissue culture, particularly in comparison with 2, 4-D in detail.
基金support from the Natural Science Foundation of Shandong Province,China (ZR2015CM036)the Molecular Foundation of Main Crop Quality,the Ministry of Science and Technology of China (2016YFD0100500)+1 种基金the Project of Science and Technology of Shandong “Wheat Breeding by Molecular Design”,China (2016LZGC023)the Research Fund for Agricultural Big Data Project,China
文摘Dissecting the genetic relationships among gluten-related traits is important for high quality wheat breeding. Quantitative trait loci(QTLs) analysis for gluten strength,as measured by sedimentation volume(SV) and gluten index(GI),was performed using the QTLNetwork 2.0 software. Recombinant inbred lines(RILs) derived from the winter wheat varieties Shannong 01-35×Gaocheng 9411 were used for the study. A total of seven additive QTLs for gluten strength were identified using an unconditional analysis. QGi1 D-13 and QSv1 D-14 were detected through unconditional and conditional QTLs mapping,which explained 9.15–45.08% of the phenotypic variation. QTLs only identified under conditional QTL mapping were located in three marker intervals:WPT-3743–GLU-D1(1 D),WPT-7001–WMC258(1 B),and WPT-8682–WPT-5562(1 B). Six pairs of epistatic QTLs distributed nine chromosomes were identified. Of these,two main effect QTLs(QGi1 D-13 and QSv1 D-14) and 12 pairs of epistatic QTLs were involved in interactions with the environment. The results indicated that chromosomes 1 B and 1 D are important for the improvement of gluten strength in common wheat. The combination of conditional and unconditional QTLs mapping could be useful for a better understanding of the interdependence of different traits at the QTL molecular level.
基金supported by the National Natural Science Foundation of China (31201674 and 31371618)the Natural Science Foundation of Hebei Province, China (C2011204031)the Key Laboratory of Crop Growth Regulation of Hebei Province, China
文摘Zinc finger protein(ZFP) genes comprise a large and diverse gene family, and are involved in biotic and abiotic stress responses in plants. In this study, a total of 126 ZFP genes classified into various types in wheat were characterized and subjected to expression pattern analysis under inorganic phosphate(Pi) deprivation. The wheat ZFP genes and their corresponding GenBank numbers were obtained from the information of a 4×44K wheat gene expression microarray chip. They were confirmed by sequence similarity analysis and named based on their homologs in Brachypodium distachyon or Oriza sativa. Expression analysis based on the microarray chip revealed that these ZFP genes are categorized into 11 classes according to their gene expression patterns in a 24-h of Pi deprivation regime. Among them, ten genes were differentially up-regulated, ten genes differentially downregulated, and two genes both differentially up- and down-regulated by Pi deprivation. The differentially up- or down-regulated genes exhibited significantly more or less transcripts at one, two, or all of the checking time points(1, 6, and 24 h) of Pi stress in comparison with those of normal growth, respectively. The both differentially up- and down-regulated genes exhibited contrasting expression patterns, of these, TaWRKY70;5 showed significantly up-regulated at 1 and 6 h and down-regulated at 24 h whereas TaAN1AN20-8;2 displayed significantly upregulated at 1 h and downregulated at 6 h under deprivation Pi condition. Real time PCR analysis confirmed the expression patterns of the differentially expressed genes obtained by the microarray chip. Our results indicate that numerous ZFP genes in wheat respond to Pi deprivation and have provided further insight into the molecular basis that plants respond to Pi deprivation mediated by the ZFP gene family.
基金financially supported by the National Natural Science Foundation of China (31371618,31201674)the National Transgenic Major Program of China (2011ZX08008)the Key Laboratory of Crop Growth Regulation of Hebei Province,China
文摘Mitogen-activated protein kinase(MPK) cascades consist of a set of kinase types(MPKKKs,MPKKs,MPKs) to establish conserved signal-transducing modules mediating plant growth,development as well as responses to internal and external cues.In this study,the expression patterns of six MPKKK,two MPKK,and 11 MPK genes in wheat in responses to external treatments of phytohormones,including naphthylacetic acid(NAA),abscisic acid(ABA),6-benzyladenine(6-BA),gibberellin(GA_3),salisylic acid(SA),jasmonic acid(JA),and ethylene(ETH),were investigated.Expression analysis revealed that several of the MPK cascade genes are responses to the external phytohormone signaling.Of which,TaMPKKKA;3is induced by 6-BA and NAA while TaMPK4 repressed by ETH,GA_3,SA,and JA;TaMPKKKA,TaMPKKKA;3 and TaMPK1 are down-regulated by ETH and GA_3whereas TaMPK9 and TaMPK12 repressed by ETH and JA in addition that TaMPK12 also repressed by GA_3;TaMPK12;1 is down-regulated by ABA,GA_3 and SA while TaMPK17 repressed by all exogenous phytonormones examined.TaMPK4,a MPK type gene previously characterized to mediate tolerance to phosphate(Pi)deprivation,was functionally evaluated for its role in mediation of responses of plants to exogenous GA_3,ETH,SA,and JA.Results indicated that overexpression and antisense expression of TaMPK4 in tobacco dramatically modify the growth of seedlings upon treatments of GA_3,SA and JA,in which the overexpressors behaved deteriorated growth feature whereas the seedlings with antisense expression of TaMPK4 exhibited improved seedling phenotype.The growth behaviors in lines overexpressing or antisensely expressing TaMPK4 are closely associated with the biomass and the corresponding hormone-associated parameters.These results demonstrated that TaMPK4 acts as a critical player in mediating the phytohormone signaling.Our findings have identified the phytohormone-responsive MPK cascade genes in wheat and provided a connection between the phytohormone-mediated responses and the MPK cascade pathways.
基金funded by Foundation for Excellent Youth Scholars of CAREERI,CAS (Y451081001)National Natural Science Foundation of China (41401620,41201249)The Chinese Academy of Sciences has kindly granted Prof.O. Andrén a 'Professorship for Senior International Scientists' (Grant No.Y229D91001)
文摘Growth and physiological responses of wheat to sand burial were studied in Horqin Sandy Land, to determine the impact on productivity and survival as well as antioxidant enzymes responses. This study consisted of one control(no sand) and four sand burial treatments: 25%, 50%, 75% and 100% of seedling height, respectively. Minor burial(25%) had no effect on wheat growth and survival; deep burial(100%) was fatal, and the others had an intermediate effect. Thus, the survival limit to sand burial was equal to seedling height. Sand burial mainly decreased shoot biomass and crop yield, but had small effects on belowground biomass. Superoxide dismutase(SOD) activity increased with time after burial in all treatments with surviving plants. Peroxidase(POD) activity increased after six days under burial, and catalase(CAT) activity decreased after burial, but recovered after 12 days. The concentration of malondialdehyde(MDA), a marker for oxidative stress, was low on the sixth day, but increased thereafter with burial depth. Thus, sand burial >25% should be avoided due to growth rate reduction leading to reduced crop yield, and even 25% burial showed physiological indicators of stress.
文摘<span style="font-family:Verdana;">A field trial was conducted at a private farm in AL-Hashimiya district Babylon Governorate—the republic of Iraq during the 2016</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">2017 and 2017</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">2018 growing seasons.</span><span style="color:red;"> </span><span style="font-family:Verdana;">This study was conducted using two irrigation methods, sprinkler and surface irrigation, for each of them had three Tillage methods (zero-tillage</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> medium-tillage</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> deep-tillage) and each tillage system had four seeding rate of wheat yield (120</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">180</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">240</span><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;">300) kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">.</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">Results indicated that the consumptive water use was 557.5 and</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">535.9 mm for surface irrigation and 460.9 and 442.6 mm for sprinkler irrigation in </span><span style="font-family:Verdana;">the </span><span style="font-family:;" "=""><span style="font-family:Verdana;">2016-2017 and 2017-2018 growing seasons. Sprinkler irrigation significantly increased the flag leaf area with no significant effect on plant height. However, the minimum tillage and seeding rate (240 kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup></span><span style="font-family:;" "=""><span style="font-family:Verdana;">) significantly increased the plant height and flag leaf </span><span style="font-family:Verdana;">area in both growing seasons. For the grain yield, the sprinkler irrigation, m</span><span style="font-family:Verdana;">inimum tillage, and seeding rate (240 </span></span><span style="font-family:;" "=""><span style="font-family:Verdana;">kg<span style="white-space:nowrap;">∙</span>ha</span><sup><span style="font-family:Verdana;">-1</span></sup></span><span style="font-family:;" "=""><span style="font-family:Verdana;">) also increased the plant height and flag leaf area by 13%, 10, % 11%, 11%, 12%, and 14% in both growing seasons, respectively, through an increased number of spikes/m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, the number of grain spike-1, and 1000-grain weight in both growing seasons, respe</span></span><span style="font-family:Verdana;">ctively. Interestingly the grain yield was increased by 33% and 32% in both growing seasons under the effects of these three factors altogether, respectively. It can be concluded that these factors act synergistically, resulting in a significant improvement in the wheat grain-yield of, less consumptive water use, and high water use efficiency.</span>
基金supported by the National Key Research and Development Program of China(2017YFD0300906-07)
文摘Wheat leaf rust,caused by Puccinia triticina(Pt),is an important foliar disease that has an important influence on wheat yield.The most economic,safe and effective way to control the disease is growing resistant cultivars.In the present study,a total of 46 wheat landraces and 34 wheat lines with known Lr(leaf rust resistance)genes were inoculated with 16Pt pathotypes for postulating seedling resistance gene(s)in the greenhouse.These cultivars and five wheat differential lines with adult plant resistance(APR)genes(Lr12,Lr22b,Lr34,Lr35 and Lr37)were also evaluated for identification of slow rusting resistance in the field trials in Baoding,Hebei Province of China in the 2014–2015 and 2015–2016 cropping seasons.Furthermore,10 functional molecular markers closely linked to 10 known Lr genes were used to detect all the wheat genotypes.Results showed that most of the landraces were susceptible to most of the Pt pathotypes at seedling stage.Nonetheless,Lr1 was detected only in Hongtangliangmai.The field experimental test of the two environments showed that 38 landraces showed slow rusting resistance.Seven cultivars possessed Lr34 but none of the landraces contained Lr37 and Lr46.Lr genes namely,Lr9,Lr19,Lr24,Lr28,Lr29,Lr47,Lr51 and Lr53 were effective at the whole plant stage.Lr18,Lr36 and Lr45 had lost resistance to part of pathotypes at the seedling stage but showed high resistance at the adult plant stage.Lr34 as a slowing rusting gene showed good resistance in the field.Four race-specific APR genes Lr12,Lr13,Lr35 and Lr37 conferred good resistance in the field experiments.Seven race-specific genes,Lr2b,Lr2c,Lr11,Lr16,Lr26,Lr33 and LrB had lost resistance.The 38 landraces showed slow rusting resistance to wheat leaf rust can be used as resistance resources for wheat resistance breeding in China.
基金supported by the National Natural Science Foundation of China (31571664 and 31671686)the Key Research and Development Project of Hebei, China (17962901D)
文摘Plant N starvation response is closely associated with the N signaling components that involve transduction of the low-N cues. In this study, we functionally characterized Ta ARR1, a cytokinin(CK) response regulator gene in Triticum aestivum, in mediating the N starvation adaptation in plants. Ta ARR1 harbors two conserved domains specified by plant ARR family members;subcellular localization analysis indicated its target onto nucleus after endoplasmic reticulum assortment. Ta ARR1 displayed modified expression upon the N starvation stressor, showing upregulated expression in roots and leaves over a 27-h N starvation treatment and whose induced transcripts were gradually recovered along with progression of the N recovery treatment. The tobacco lines overexpressing Ta ARR1 displayed improved low-N stress tolerance, displaying enlarged phenotype, increased biomass and N accumulation, and enhanced glutamine synthetase(GS) activities compared with wild type(WT) following the N starvation treatment. Expression analysis on genes encoding the nitrate transporter(NRT) and GS proteins in Nicotiana tabacum revealed that Nt NRT2.2 and Nt GS3 are upregulated in expression in the N-deprived transgenic lines, whose expression patterns were contrasted to other above family genes that were unaltered on transcripts between the transgenic lines and WT. Transgene analysis validated the function of Nt NRT2.2 and Nt GS3 in regulating N accumulation, GS activity, growth traits, and N use efficiency in plants. These results suggested the internal connection between the Ta ARR1-mediated N starvation tolerance and the modified transcription of distinct N acquisitionand assimilation-associated genes. Our investigation together indicates that Ta ARR1 is essential in plant N starvation adaptation due to the gene function in transcriptionally regulating distinct NRT and GS genes that affect plant N uptake and assimilation under the N starvation condition.
