The spikelet number per spike (SNS) contributes greatly to grain yield in wheat. Identifying various genes that control wheat SNS is vital for yield improvement. This study used a recombinant inbred ...line population genotyped by the Wheat55K single-nucleotide polymorphism array to identify two major and stably expressed quantitative trait loci (QTLs) for SNS. One of them (QSns.sau-2SY-2D.1) was reported previously, while the other (QSns.sau-2SY-7A) was newly detected and further analyzed in this study. QSns.sau-2SY-7A had a high LOD value ranging from 4.46 to 16.00 and explained 10.21–40.78％ of the phenotypic variances. QSns.sau-2SY-7A was flanked by the markers AX-110518554 and AX-110094527 in a 4.75-cM interval on chromosome arm 7AL. The contributions and interactions of both major QTLs were further analyzed and discussed. The effect of QSns.sau-2SY-7A was successfully validated by developing a tightly linked kompetitive allele specific PCR marker in an F2:3 population and a panel of 101 high-generation breeding wheat lines. Furthermore, several genes including the previously reported WHEAT ORTHOLOG OF APO1 (WAPO1), an ortholog of the rice gene ABERRANT PANICLE ORGANIZATION 1 (APO1) related to SNS, were predicted in the interval of QSns.sau-2SY-7A. In summary, these results revealed the genetic basis of the multi-spikelet genotype of wheat line 20828 and will facilitate subsequent fine mapping and breeding utilization of the major QTLs.
Anthocyanin-rich barley can have great potential in promoting human health and in developing nutraceuticals and functional foods. As different anthocyanin compounds have different antioxidant ...activities, breeding cultivars with pre-designed anthocyanin compositions could be highly desirable. Working toward this possibility, we assessed and reported for the first time the genetic control of individual anthocyanin compounds in barley. Of the ten anthocyanins assessed, two, peonidin-3-glucoside (P3G) and cyanidin-3-glucoside (C3G), were major components in the purple pericarp barley genotype RUSSIA68. Quantitative trait locus (QTL) mapping showed that both anthocyanin compounds were the interactive products of two loci, one located on chromosome arm 2HL and the other on 7HS. However, the two different anthocyanin components seem to be controlled by different interactions between the two loci. The effects of the 7HS locus on P3G and C3G were difficult to detect without removing the effect of the 2HL locus. At least one copy of the 2HL alleles from the purple pericarp parent was required for the synthesis of P3G. This does not seem to be the case for the production of C3G which was produced in each of all the different allele combinations between the two loci. Typical maternal effect was also observed in the inheritance of purple pericarp grains in barley. The varied values of different compounds, coupled with their different genetic controls, highlight the need for targeting individual anthocyanins in crop breeding and food processing.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Depression is prevalent among university students worldwide, and the prevalence appears to be increasing. As an intermediate stage between being healthy and having depression, students with ...subthreshold depression could develop worsening depression or recover with intervention to prevent depression. The Center for Epidemiologic Studies Depression Scale (CES-D) is a useful tool to assess subthreshold depression. The primary purpose of the current study was to evaluate the psychometric characteristics of CES-D in Chinese university students. Secondly, we aimed to describe the prevalence of subthreshold depression among the student sample and examine its demographic correlates.
A total of 2,068 university students participated in the study, and they were asked to respond to the Chinese CES-D, Beck Depression Inventory-II (BDI-II), and Positive and Negative Affect Schedule (PANAS). The factor structure was evaluated by conducting exploratory (EFA) and confirmatory factor analysis (CFA) using a structural equation modeling approach. The reliability was assessed by calculating Cronbach's alpha, inter-item correlation, and item-total correlation coefficients. The prevalence of subthreshold depression was calculated and demographic correlates of gender, grade, and major were examined by multiple regression.
The final sample included 1,920 participants. The EFA results suggested extraction of three factors (somatic symptoms, negative affect, and anhedonia) that account for 52.68% of total variance. The CFA results suggested that the newly derived model with 14 items was the best fit for our data. Six items were removed from the original scale (item 9, 10, 13, 15, 17, and 19). The Cronbach's alpha of the 14-item CES-D was 0.87. The prevalence of subthreshold depression among university students reached 32.7% for the 20-item CES-D and 31% for the 14-item CES-D, although there was no significant difference of prevalence in gender, grade, and major.
The CES-D has good reliability and validity for assessing subthreshold depression in Chinese university students.
ATP-binding cassette (ABC) transporters hydrolyze ATP to transport a wide range of substrates.
is a major causal agent of Fusarium head blight, which is a severe disease in wheat worldwide.
(
) ...encodes an ABC-C (ABC transporter family C) transporter in
, which was highly expressed during the infection in wheat and was up-regulated by the plant defense hormone salicylic acid (SA) and the fungicide tebuconazole. The predicted tertiary structure of the FgABCC9 protein was consistent with the schematic of the ABC exporter. Deletion of
resulted in decreased mycelial growth, increased sensitivity to SA and tebuconazole, reduced accumulation of deoxynivalenol (DON), and less pathogenicity towards wheat. Re-introduction of a functional
gene into Δ
recovered the phenotypes of the wild type strain. Transgenic expression of
in
increased the accumulation of SA in its leaves without activating SA signaling, which suggests that
functions as an SA exporter. Taken together,
encodes an ABC exporter, which is critical for fungal exportation of SA, response to tebuconazole, mycelial growth, and pathogenicity towards wheat.
Phytohormones are key regulators of plant growth, development, and signalling networks involved in responses to diverse biotic and abiotic stresses. Transcriptional reference maps of hormone ...responses have been reported for several model plant species such as Arabidopsis thaliana, Oryza sativa, and Brachypodium distachyon. However, because of species differences and the complexity of the wheat genome, these transcriptome data are not appropriate reference material for wheat studies.
We comprehensively analysed the transcriptomic responses in wheat spikes to seven phytohormones, including indole acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA), ethylene (ET), cytokinin (CK), salicylic acid (SA), and methyl jasmonic acid (MeJA). A total of 3386 genes were differentially expressed at 24 h after the hormone treatments. Furthermore, 22.7% of these genes exhibited overlapping transcriptional responses for at least two hormones, implying there is crosstalk among phytohormones. We subsequently identified genes with expression levels that were significantly and differentially induced by a specific phytohormone (i.e., hormone-specific responses). The data for these hormone-responsive genes were then compared with the transcriptome data for wheat spikes exposed to biotic (Fusarium head blight) and abiotic (water deficit) stresses.
Our data were used to develop a transcriptional reference map of hormone responses in wheat spikes.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
High-molecular-weight glutenin subunits (HMW-GSs) are the most critical grain storage proteins that determine the unique processing qualities of wheat. Although it is a part of the superior HMW-GS ...pair (Dx5+Dy10), the contribution of the Dy10 subunit to wheat processing quality remains unclear. In this study, we elucidated the effect of Dy10 on wheat processing quality by generating and analyzing a deletion mutant (with the Dy10-null allele), and by elucidating the changes to wheat flour following the incorporation of purified Dy10. The Dy10-null allele was transcribed normally, but the Dy10 subunit was lacking. These findings implied that the Dy10-null allele reduced the glutenin:gliadin ratio and negatively affected dough strength (i.e., Zeleny sedimentation value, gluten index, and dough development and stability times) and the bread-making quality; however, it positively affected the biscuit-making quality. The incorporation of various amounts of purified Dy10 into wheat flour had a detrimental effect on biscuit-making quality. The results of this study demonstrate that the Dy10 subunit is essential for maintaining wheat dough strength. Furthermore, the Dy10-null allele may be exploited by soft wheat breeding programs.
De-domestication is a unique evolutionary process during which crops re-acquire wild-like traits to survive and persist in agricultural fields without the need for human cultivation. The ...re-acquisition of seed dispersal mechanisms is crucial for crop de-domestication. Common wheat is an important cereal crop worldwide. Tibetan semi-wild wheat is a potential de-domesticated common wheat subspecies. However, the crucial genes responsible for its brittle rachis trait have not been identified.
Genetic mapping, functional analyses and phylogenetic analyses were completed to identify the gene associated with Qbr.sau-5A, which is a major locus for the brittle rachis trait of Tibetan semi-wild wheat.
The cloned Qbr.sau-5A gene is a new Q allele (Qt
) with a 161-bp transposon insertion in exon 5. Although Qt
is expressed normally, its encoded peptide lacks some key features of the APETALA2 family. The abnormal functions of Q
t in developing wheat spikes result in brittle rachises. Phylogenetic and genotyping analyses confirmed that Qt
originated from Q in common wheat and is naturally distributed only in Tibetan semi-wild wheat populations.
The identification of Qt
provides new evidence regarding the origin of Tibetan semi-wild wheat, and new insights into the re-acquisition of wild traits during crop de-domestication.
Micronutrient malnutrition affects over three billion people worldwide, especially women and children in developing countries. Increasing the bioavailable concentrations of essential elements in the ...edible portions of crops is an effective resolution to address this issue. To determine the genetic factors controlling micronutrient concentration in wheat, the quantitative trait locus （QTL） analysis for iron, zinc, copper, manganese, and selenium concentrations in two recombinant inbred line populations was performed. In all, 39 QTLs for ifve micronutrient concentrations were identiifed in this study. Of these, 22 alleles from synthetic wheat SHW-L1 and seven alleles from the progeny line of the synthetic wheat Chuanmai 42 showed an increase in micronutrient concentrations. Five QTLs on chromosomes 2A, 3D, 4D, and 5B found in both the populations showed signiifcant phenotypic variation for 2-3 micronutrient concentrations. Our results might help understand the genetic control of micronutrient concentration and allow the utilization of genetic resources of synthetic hexaploid wheat for improving micronutrient efifciency of cultivated wheat by using molecular marker-assisted selection.
Salicylic acid (SA) is a key defense hormone associated with wheat resistance against Fusarium head blight, which is a severe disease mainly caused by
. Although
can metabolize SA, it remains unclear ...how this metabolic activity affects the wheat⁻
interaction. In this study, we identified a salicylate hydroxylase gene (
;
) in
. This gene encodes a protein that catalyzes the conversion of SA to catechol. Additionally, FgNahG was widely distributed within hyphae. Disrupting the
gene (Δ
) led to enhanced sensitivity to SA, increased accumulation of SA in wheat spikes during the early infection stage and inhibited development of head blight symptoms. However,
did not affect mycotoxin production. Re-introducing a functional
gene into the Δ
mutant recovered the wild-type phenotype. Moreover, the expression of
in transgenic
decreased the SA concentration and the resistance of leaves to
. These results indicate that the endogenous SA in wheat influences the resistance against
. Furthermore, the capacity to metabolize SA is an important factor affecting the ability of
to infect wheat plants.
Tibetan semiwild wheat (Triticum aestivum ssp. tibetanum Shao) is a primitive hexaploid wheat resource found in Tibet. It is characterized by tolerance to nutrition deficiency and strong seed ...dormancy and has potential to be useful in wheat breeding programs. To tap the advantages of Tibetan semiwild wheat in wheat breeding, we investigated nine agronomic traits including heading date (HD), anthesis date (AD), plant height (PHT), tiller number (TN), spike length (SL), spikelet number per spike (SNS), spikelet density (DS), grain weight per spike (GWS), and 1000‐grain weight (TGW) in 186 recombinant inbred lines from a cross between Tibetan semiwild wheat ‘Q1028’ and common wheat ‘Zhengmai 9023’ (ZM 9023) across three growing seasons. Forty‐five qualitative trait loci (QTLs) on 12 chromosomes were detected. The phenotypic variation explained by each of these QTL ranged from 4.7 to 29.7%. Positive alleles for 28 of these QTLs were derived from Q1028. Of these QTLs, 25 (56%) were detected in at least two growing seasons. Fifteen stable QTLs that were significant across all three growing seasons were identified. Novel QTLs derived from Q1028 were identified, such as QSd.sau‐7A for spikelet density, QTgw.sau‐2B for TGW and QSns.sau‐3D for SNS. Eleven QTL clusters were detected, including one on chromosome 5A flanked by the markers wPt‐9094 and wPt‐9513. This cluster consists of QTLs controlling HD, AN, PHT, SL, and spikelet density and explained 6.6 to 12.6% of the phenotypic variation in these traits. The QTLs and molecular markers identified here could be useful in fine mapping and breeding programs.
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