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Introduction: The production of root exudates with biological nitrification inhibition (BNI) effects is a strategy adopted by ammonium-N ( N H 4 + - N ) tolerant plant species that occur in N-limited environments. Most knowledge on BNI comes from plant species that occur in acidic soils., Methods: Here, combining field sampling and laboratory culture, we assessed the BNI-capacity of Leymus chinensis , a dominant grass species in alkaline grasslands in eastern Asia, and explored why L. chinensis has BNI ability., Results and Discussion: The results showed that L. chinensis has strong BNI-capacity. At a concentration of 1 mg mL -1 , L. chinensis ' root exudates inhibited nitrification in soils influenced by Puccinellia tenuiflora by 72.44%, while DCD only inhibited it by 68.29%. The nitrification potential of the soil of L. chinensis community was only 53% of the P. tenuiflora or 41% of the Suaeda salsa community. We also showed that the supply of N H 4 + - N driven by L. chinensis ' BNI can meet its requirements . In addition, N H 4 + - N can enhance plant adaptation to alkaline stress by regulating pH, and in turn, the uptake of nitrate-N ( NO 3 - - N ). We further demonstrated that the regulatory function of N H 4 + - N is greater than its nutritional function in alkaline environment. The results offer novel insights into how L. chinensis adapts to high pH and nutrient deficiency stress by secreting BNIs, and reveal, for the first time, differences in the functional roles of N H 4 + - N and NO 3 - - N in growth and adaptation under alkaline conditions in a grass species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Zhang, Guo, Shi, Zhai, Yao, Yang, Xin, Cui, Li, Ma and Sun.)

Leaves comprise one of the most important organs for plant growth and development. Although there have been some reports on leaf development and the establishment of leaf polarity, their regulatory mechanisms are not very clear. In this study, we isolated a NAC (NAM, ATAF, and CUC) transcription factor (TF), i.e., IbNAC43 , from Ipomoea trifida , which is a wild ancestor of sweet potato. This TF was highly expressed in the leaves and encoded a nuclear localization protein. The overexpression of IbNAC43 caused leaf curling and inhibited the growth and development of transgenic sweet potato plants. The chlorophyll content and photosynthetic rate in transgenic sweet potato plants were significantly lower than those in wild-type (WT) plants. Scanning electron microscopy (SEM) and paraffin sections showed that the ratio of cells in the upper and lower epidermis of the transgenic plant leaves was unbalanced; moreover, the abaxial epidermal cells were irregular and uneven in transgenic plants. In addition, the xylem of transgenic plants was more developed than that of WT plants, while their lignin and cellulose contents were significantly higher than those of WT. Quantitative real-time PCR (qRT-PCR) analysis showed that the overexpression of IbNAC43 upregulated the genes involved in leaf polarity development and lignin biosynthesis in transgenic plants. Moreover, it was found that IbNAC43 could directly activate the expression of the leaf adaxial polarity-related genes IbREV and IbAS1 by binding to their promoters. These results indicate that IbNAC43 might play a critical role in plant growth by affecting the establishment of leaf adaxial polarity. This study provides new insights regarding leaf development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Sun, Li, Nie, Chen, Gao, Zhang, He, Liu and Zhai.)

The distribution of elite soybean ( Glycine max ) cultivars is limited due to their highly sensitive to photoperiod, which affects the flowering time and plant architecture. The recent emergence of CRISPR/Cas9 technology has uncovered new opportunities for genetic manipulation of soybean. The major maturity gene E1 of soybean plays a critical role in soybean photoperiod response. Here, we performed CRISPR/Cas9-mediated targeted mutation of E1 gene in soybean cultivar Tianlong1 carrying the dominant E1 to investigate its precise function in photoperiod regulation, especially in plant architecture regulation. Four types of mutations in the E1 coding region were generated. No off-target effects were observed, and homozygous trans-clean mutants without T-DNA were obtained. The photoperiod sensitivity of e1 mutants decreased relative to the wild type plants; however, e1 mutants still responded to photoperiod. Further analysis revealed that the homologs of E1 , E1 - La , and E1 - Lb , were up-regulated in the e1 mutants, indicating a genetic compensation response of E1 and its homologs. The e1 mutants exhibited significant changes in the architecture, including initiation of terminal flowering, formation of determinate stems, and decreased branch numbers. To identify E1 -regulated genes related to plant architecture, transcriptome deep sequencing (RNA-seq) was used to compare the gene expression profiles in the stem tip of the wild-type soybean cultivar and the e1 mutants. The expression of shoot identity gene Dt1 was significantly decreased, while Dt2 was significantly upregulated. Also, a set of MADS-box genes was up-regulated in the stem tip of e1 mutants which might contribute to the determinate stem growth habit., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wan, Liu, Guo, Fan, Liu, Xu, Zhu, Quan, Lu, Bai and Zhai.)

Small open reading frames (sORFs) can encode functional polypeptides or act as cis -translational regulators in stress responses in eukaryotes. Their number and potential importance have only recently become clear in plants. In this study, we identified a novel sORF gene in sweet potato, IbEGF , which encoded the 83-amino acid polypeptide containing an EGF_CA domain. The expression of IbEGF was induced by PEG6000, H 2 O 2 , abscisic acid (ABA), methyl-jasmonate (MeJA) and brassinosteroid (BR). The IbEGF protein was localized to the nucleus and cell membrane. Under drought stress, overexpression of IbEGF enhanced drought tolerance, promoted the accumulation of ABA, MeJA, BR and proline and upregulated the genes encoding superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in transgenic sweet potato. The IbEGF protein was found to interact with IbCOP9-5α, a regulator in the phytohormone signalling pathways. These results suggest that IbEGF interacting with IbCOP9-5α enhances drought tolerance by regulating phytohormone signalling pathways, increasing proline accumulation and further activating reactive oxygen species (ROS) scavenging system in transgenic sweet potato., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhou, Zhai, Xing, Wei, He, Zhang, Gao, Zhao and Liu.)

A comprehensive study in selenium (Se) biofortification of staple food is vital for the prevention of Se-deficiency-related diseases in human beings. Thus, the roles of exogenous Se species, application methods and rates, and wheat growth stages were investigated on Se accumulation in different parts of wheat plant, and on Se speciation and bioaccessibility in whole wheat and white all-purpose flours. Soil Se application at 2 mg kg -1 increased grains yield by 6% compared to control (no Se), while no significant effects on yield were observed with foliar Se treatments. Foliar and soil Se application of either selenate or selenite significantly increased the Se content in different parts of wheat, while selenate had higher bioavailability than selenite in the soil. Regardless of Se application methods, the Se content of the first node was always higher than the first internode. Selenomethionine (SeMet; 87-96%) and selenocystine (SeCys 2 ; 4-13%) were the main Se species identified in grains of wheat. The percentage of SeMet increased by 6% in soil with applied selenite and selenate treatments at 0.5 mg kg -1 and decreased by 12% compared with soil applied selenite and selenate at 2 mg kg -1 , respectively. In addition, flour processing resulted in losses of Se; the losses were 12-68% in white all-purpose flour compared with whole wheat flour. The Se bioaccessibility in whole wheat and white all-purpose flours for all Se treatments ranged from 6 to 38%. In summary, foliar application of 5 mg L -1 Se(IV) produced wheat grains that when grounds into whole wheat flour, was the most efficient strategy in producing Se-biofortified wheat. This study provides an important reference for the future development of high-quality and efficient Se-enriched wheat and wheat flour processing., Competing Interests: Author NL was employed by Center of Regional Watershed Environment Comprehensive Control Technology in Jiangsu Province, Academy of Environmental Planning & Design, Co., Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Zhou, Cheng, Chen, Ma, Zhai, Qi, Liu, Liu, Meng, Bañuelos and Liang.)

Dormancy is a common survival strategy in plants to temporarily suspend visible growth under unsuitable conditions. The elaborate mechanism underlying bud break in perennial woody plants is gradually illustrated. Here, we identified a grape vine WRKY transcription factor, VvWRKY37 , which was highly expressed in dormant buds. It was particularly induced by the application of exogenous abscisic acid, and depressed on exposure to gibberellin and low temperature (4°C) stress at the transcript level. The yeast one-hybrid assay confirmed that VvWRKY37 had a transcriptional activity. Ectopic over-expression of VvWRKY37 significantly delayed bud break of transgenic poplar plants. As an ABA-inducible gene, VvWRKY37 also depressed the expression of ABA catabolic gene CYP707A s and enhanced the accumulation of endogenous ABA in transgenic poplar plants. The molecular pieces of evidence showed that VvWRKY37 preferentially recognized and bound W-box 5'-G/CATTGACT/C/G-3' cis -element in vitro . Additionally, VvABI5 and VvABF2 acted as the upstream transcriptional activators of VvWRKY37 via protein-DNA interactions. Taken together, our findings provided valuable insights into a new regulatory mechanism of WRKY TF by which it modulates bud break through ABA-mediated signaling pathways., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Zhao, Zhang, Zhai, Abid and Du.)

The general concept of photoperiodism, i.e., the photoperiodic induction of flowering, was established by Garner and Allard (1920). The genetic factor controlling flowering time, maturity, or photoperiodic responses was observed in soybean soon after the discovery of the photoperiodism. E1 , E2 , and E3 were named in 1971 and, thereafter, genetically characterized. At the centennial celebration of the discovery of photoperiodism in soybean, we recount our endeavors to successfully decipher the molecular bases for the major maturity loci E1 , E2 , and E3 in soybean. Through systematic efforts, we successfully cloned the E3 gene in 2009, the E2 gene in 2011, and the E1 gene in 2012. Recently, successful identification of several circadian-related genes such as PRR3a , LUX , and J has enriched the known major E1-FTs pathway. Further research progresses on the identification of new flowering and maturity-related genes as well as coordinated regulation between flowering genes will enable us to understand profoundly flowering gene network and determinants of latitudinal adaptation in soybean., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Xia, Zhai, Wu, Xu, Watanabe and Harada.)

BTB-TAZ (BT)-domain proteins regulate plant development and pathogen defense. However, their roles in resistance to abiotic stresses remain largely unknown. In this study, we found that the sweetpotato BT protein-encoding gene IbBT4 significantly enhanced the drought tolerance of Arabidopsis . IbBT4 expression was induced by PEG6000, H 2 O 2 and brassinosteroids (BRs). The IbBT4 -overexpressing Arabidopsis seeds presented higher germination rates and longer roots in comparison with those of WT under 200 mM mannitol stress. Under drought stress the transgenic Arabidopsis plants exhibited significantly increased survival rates and BR and proline contents and decreased water loss rates, MDA content and reactive oxygen species (ROS) levels. IbBT4 overexpression upregulated the BR signaling pathway and proline biosynthesis genes and activated the ROS-scavenging system under drought stress. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays revealed that the IbBT4 protein interacts with BR-ENHANCED EXPRESSION 2 (BEE2). Taken together, these results indicate that the IbBT4 gene provides drought tolerance by enhancing both the BR signaling pathway and proline biosynthesis and further activating the ROS-scavenging system in transgenic Arabidopsis ., (Copyright © 2020 Zhou, Zhai, He, Zhu, Gao, Xing, Wei, Zhao and Liu.)

Flowering time and maturity are important agronomic traits for soybean cultivars to adapt to different latitudes and achieve maximal yield. Genetic studies on genes and quantitative trait loci (QTL) that control flowering time and maturity are extensive. In particular, the molecular bases of E1-E4 , E6 , E9 , E10 , and J have been deciphered. For a better understanding of regulation of flowering time gene networks, we need to understand if more molecular factors carrying different biological functions are also involved in the regulation of flowering time in soybeans. We developed a population derived from a cross between a landrace Jilincailihua (male) and a Chinese cultivar Chongnong16 (female). Both parents carry the same genotypes of E1e2E3HaE4 at E1 , E2 , E3 , and E4 loci. Nighty-six individuals of the F 2 population were genotyped with Illumina SoySNP8k iSelect BeadChip. A total of 2,407 polymorphic single nucleotide polymorphism (SNP) markers were used to construct a genetic linkage map. One major QTL, qFT12-1 , was mapped to an approximately 567-kB region on chromosome 12. Genotyping and phenotyping of recombinant plant whose recombination events were occurring within the QTL region allowed us to narrow down the QTL region to 56.4 kB, in which four genes were annotated. Allelism and association analysis indicated Glyma.12G073900 , a PRR7 homolog, is the strongest candidate gene for qFT12-1 . The findings of this study disclosed the possible involvement of circadian clock gene in flowering time regulation of soybeans., (Copyright © 2019 Li, Dong, Wu, Hu, Zhai, Yang and Xia.)

Several members of the MYB transcription factor family have been found to regulate growth, developmental processes, metabolism, and biotic and abiotic stress responses in plants. However, the role of MYB116 in plants is still unclear. In this study, a MYB transcription factor gene IbMYB116 was cloned and characterized from the sweetpotato [ Ipomoea batatas (L.) Lam.] line Xushu55-2, a line that is considered to be drought resistant. We show here that IbMYB116 is a nuclear protein and that it possesses a transactivation domain at the C terminus. This gene exhibited a high expression level in the leaf tissues of Xushu55-2 and was strongly induced by PEG6000 and methyl-jasmonate (MeJA). The IbMYB116 -overexpressing Arabidopsis plants showed significantly enhanced drought tolerance, increased MeJA content, and a decreased H 2 O 2 level under drought stress. The overexpression of IbMYB116 in Arabidopsis systematically upregulated jasmonic acid (JA) biosynthesis genes and activated the JA signaling pathway as well as reactive oxygen species (ROS)-scavenging system genes under drought stress conditions. The overall results suggest that the IbMYB116 gene might enhance drought tolerance by activating a ROS-scavenging system through the JA signaling pathway in transgenic Arabidopsis . These findings reveal, for the first time, the crucial role of IbMYB116 in the drought tolerance of plants.

Auxin response factors (ARFs) compose a family of transcription factors and have been found to play major roles in the process of plant growth and development. However, their roles in plant carotenoid biosynthesis and responses to abiotic stresses are rarely known to date. In the present study, we found that the IbARF5 gene from sweetpotato ( Ipomoea batatas (L.) Lam.) line HVB-3 increased the contents of carotenoids and enhanced the tolerance to salt and drought in transgenic Arabidopsis . The transgenic Arabidopsis plants exhibited the increased abscisic acid (ABA) and proline contents and superoxide dismutase (SOD) activity and the decreased H 2 O 2 content. Furthermore, it was found that IbARF5 positively regulated the genes associated with carotenoid and ABA biosynthesis and abiotic stress responses. These results suggest that IbARF5 is involved in carotenoid biosynthesis and salt and drought tolerance in transgenic Arabidopsis . This study provides a novel ARF gene for improving carotenoid contents and salt and drought tolerance of sweetpotato and other plants.

Soybean was domesticated about 5,000 to 6,000 years ago in China. Although genotyping technologies such as genotyping by sequencing (GBS) and high-density array are available, it is convenient and economical to genotype cultivars or populations using medium-density SNP array in genetic study as well as in molecular breeding. In this study, 235 cultivars, collected from China, Japan, USA, Canada and some other countries, were genotyped using SoySNP8k iSelect BeadChip with 7,189 single nucleotide polymorphisms (SNPs). In total, 4,471 polymorphic SNP markers were used to analyze population structure and perform genome-wide association study (GWAS). The most likely K value was 7, indicating this population can be divided into 7 subpopulations, which is well in accordance with the geographic origins of cultivars or accession studied. The LD decay rate was estimated at 184 kb, where r 2 dropped to half of its maximum value (0.205). GWAS using FarmCPU detected a stable quantitative trait nucleotide (QTN) for hilum color and seed color, which is consistent with the known loci or genes. Although no universal QTNs for flowering time and maturity were identified across all environments, a total of 30 consistent QTNs were detected for flowering time (R1) or maturity (R7 and R8) on 16 chromosomes, most of them were corresponding to known E1 to E4 genes or QTL region reported in SoyBase (soybase.org). Of 16 consistent QTNs for protein and oil contents, 11 QTNs were detected having antagonistic effects on protein and oil content, while 4 QTNs soly for oil content, and one QTN soly for protein content. The information gained in this study demonstrated that the usefulness of the medium-density SNP array in genotyping for genetic study and molecular breeding.

In this work, four vacuolar H + -PPase ( VHP ) genes were identified in the grape genome. Among them, VvVHP1; 2 was strongly expressed in berry skin and its expression exhibited high correlations to anthocyanin content of berry skin during berry ripening and under ABA and UVB treatments. VvVHP1; 2 was transcriptionally activated directly by VvMYBA1, and VvVHP1; 2 overexpression promoted anthocyanin accumulation in berry skins and Arabidopsis leaves; therefore, VvVHP1; 2 mediated VvMYBA1-regulated berry pigmentation. On the other hand, RNA-Seq analysis of WT and transgenic berry skins revealed that carbohydrate metabolism, flavonoid metabolism and regulation and solute carrier family expression were the most clearly altered biological processes. Further experiments elucidated that VvVHP1; 2 overexpression up-regulated the expression of the genes related to anthocyanin biosynthesis and transport via hexokinase-mediated glucose signal and thereby promoted anthocyanin accumulation in berry skins and Arabidopsis leaves. Additionally, modifications of sugar status caused by enhanced hexokinase activities likely play a key role in VvVHP1; 2- induced sugar signaling.

Grain size and shape associated with yield and milling quality are important traits in wheat domestication and breeding. To reveal the genetic factors on the D genome that control grain size and shape variation, we conducted analysis of quantitative trait loci (QTL) using the F 2 and F 2:3 populations derived from a common allohexaploid wheat line TAA10 and a synthetic allohexaploid wheat XX329, which have near-identical AABB genomes and different DD genomes. Based on genotyping using wheat 660K single nucleotide polymorphism (SNP) array, TAA10 and XX329 exhibited 96.55, 98.10, and 66.26% genetic similarities of A, B, and D genomes, respectively. Phenotypic evaluation revealed that XX329 had higher thousand grain weight (TGW), grain length, width, area and perimeter than TAA10 across all environments, and the grain yield per plot of XX329 increased by 17.43-30.36% compared with that of TAA10 in two environments. A total of nine environmentally stable QTL associated with grain size and shape were mapped on chromosomes 2D and 7D and verified using near isogenic lines (NILs), with the synthetic allohexaploid wheat XX329 contributing favorable alleles. Notably, a novel QTL QTgw.cau-2D controlling grain weight was first identified from the synthetic allohexaploid wheat, which may be a more desirable target for genetic improvement in wheat breeding. Collectively, these results provide further insights into the genetic factors that shaped the grain morphology during wheat evolution and domestication.

This study assessed the primary impacts of exogenous melatonin (MT) treatment on grape berry metabolism. Exogenous MT treatment increased the endogenous MT content and modified berry ripening. Transcriptomic analysis revealed that the processes of polyphenol metabolism, carbohydrate metabolism and ethylene biosynthesis and signaling were the three most significantly altered biological processes upon MT treatment. Further experiments verified that MT treatment increased the contents of total anthocyanins, phenols, flavonoids and proanthocyanidins in berries. Additionally, the contents of 18 of the 22 detected individual phenolic compounds were enhanced by MT treatment; particularly, the resveratrol content was largely increased concomitantly with the up-regulation of STS gene expression. Meanwhile, MT treatment enhanced the antioxidant capacity of berries. On the other hand, it was indicated that ethylene participated in the regulation of polyphenol metabolism and antioxidant capacity under MT treatment in grape berries. In summary, MT enhances the polyphenol content and antioxidant capacity of grape berries partially via ethylene signaling.

It has been well-demonstrated that the control of plasma membrane H + -ATPase (PM H + -ATPase) activity is important to plant salt tolerance. This study found a significant increase in PM H + -ATPase (PMA) activity in grape root exposed to NaCl. Furthermore, 7 Vitis vinifera PM H + -ATPase genes ( VvPMAs ) were identified within the grape genome and the expression response of these VvPMAs in grape root under salinity was analyzed. Two VvPMAs ( VvPMA1 and VvPMA3 ) were expressed more strongly in roots than the other five VvPMAs . Moreover, roots exhibited diverse patterns of gene expression of VvPMA1 and VvPMA3 responses to salt stress. Interestingly, two transcripts of VvPMA1 , which were created through alternative splicing (AS), were discovered and isolated from salt stressed root. Comparing the two VvPMA1 cDNA sequences (designated VvPMA1 α and VvPMA1 β) with the genomic sequence revealed that the second intron was retained in the VvPMA1 β cDNA. This intron retention was predicted to generate a novel VvPMA1 through N-terminal truncation because of a 5'- terminal frame shift. Yeast complementation assays of the two splice variants showed that VvPMA1 β could enhance the ability to complement Saccharomyces cerevisiae deficient in PM H + -ATPase activity. In addition, the expression profiles of VvPMA1 α and VvPMA1 β differed under salinity. Our data suggests that through AS, the N-terminal length of VvPMA1 may be regulated to accurately modulate PM H + -ATPase activity of grape root in salt stress.

Early responsive to dehydration ( ERD ) genes can be rapidly induced to counteract abiotic stresses, such as drought, low temperatures or high salinities. Here, we report on an ERD gene ( VaERD15 ) related to cold tolerance from Chinese wild Vitis amurensis accession 'Heilongjiang seedling'. The full-length VaERD15 cDNA is 685 bp, including a 66 bp 5'-untranslated region (UTR), a 196 bp 3'-UTR region and a 423 bp open reading frame encoding 140 amino acids. The VaERD15 protein shares a high amino acid sequence similarity with ERD15 of Arabidopsis thaliana . In our study, VaERD15 was shown to have a nucleic localization function and a transcriptional activation function. Semi-quantitative PCR and Western blot analyses showed that VaERD15 was constitutively expressed in young leaves, stems and roots of V. amurensis accession 'Heilongjiang seedling' plants, and expression levels increased after low-temperature treatment. We also generated a transgenic Arabidopsis Col-0 line that over-expressed VaERD15 and carried out a cold-treatment assay. Real-time quantitative PCR (qRT-PCR) and Western blot analyses showed that as the duration of cold treatment increased, the expression of both gene and protein levels increased continuously in the transgenic plants, while almost no expression was detected in the wild type Arabidopsis . Moreover, the plants that over-expressed VaERD15 showed higher cold tolerance and accumulation of proline, soluble sugars, proteins, malondialdehyde and three antioxidases (superoxide dismutase, peroxidase, and catalase). Lower levels of relative ion leakage also occurred under cold stress. Taken together, our results indicate that the transcription factor VaERD15 was induced by cold stress and was able to enhance cold tolerance.

SWEET (Sugars Will Eventually be Exported Transporter) proteins, a novel family of sugar transporters, mediate the diffusion of sugars across cell membranes and acts as key players in sucrose phloem loading. Manipulation of SWEET genes in plants leads to various effects on resistance to biotic and abiotic stresses due to disruption of sugar efflux and changes in sugar distribution. In this study, a member of the SWEET gene family, IbSWEET10 , was cloned from the sweet potato line ND98. mRNA expression analysis in sweet potato and promoter β-Glucuronidase analysis in Arabidopsis showed that IbSWEET10 is highly expressed in leaves, especially in vascular tissue. Transient expression in tobacco epidermal cells revealed plasma membrane localization of IbSWEET10, and heterologous expression assays in yeast indicated that IbSWEET10 encodes a sucrose transporter. The expression level of IbSWEET10 was significantly up-regulated in sweet potato infected with Fusarium oxysporum Schlecht. f. sp. batatas. Further characterization revealed IbSWEET10 -overexpressing sweet potato lines to be more resistant to F. oxysporum , exhibiting better growth after infection compared with the control; conversely, RNA interference (RNAi) lines showed the opposite results. Additionally, the sugar content of IbSWEET10 -overexpression sweet potato was significantly reduced, whereas that in RNAi plants was significantly increased compared with the control. Therefore, we suggest that the reduction in sugar content caused by IbSWEET10 overexpression is the major reason for the enhanced F. oxysporum resistance of the transgenic plants. This is the first report that the IbSWEET10 transporter contributes to the resistance of sweet potato to F. oxysporum . The IbSWEET10 gene has the great potential to be used for improving the resistance to F. oxysporum in sweet potato and other plants.

Wheat yield can be enhanced by modifying the spike morphology and the plant height. In this study, a population of 191 F 9 recombinant inbred lines (RILs) was developed from a cross between two winter cultivars Yumai 8679 and Jing 411. A dense genetic linkage map with 10,816 markers was constructed by incorporating single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) marker information. Five spike morphological traits and plant height were evaluated under nine environments for the RILs and parental lines, and the number of detected environmentally stable QTLs were 18 and three, respectively. The 1RS/1BL (rye) translocation increased both spike length and spikelet number with constant spikelet compactness. The QPht.cau-2D.1 was identical to gene Rht8 , which decreased spike length without modifying spikelet number. Notably, four novel QTLs locating on chromosomes 1AS ( QSc.cau-1A.1 ), 2DS ( QSc.cau-2D.1 ), and 7BS ( QSl.cau-7B.1 and QSl.cau-7B.2 ) were firstly identified in this study, which provide further insights into the genetic factors that shaped the spike morphology in wheat. Moreover, SNP markers tightly linked to previously reported QTLs will eventually facilitate future studies including their positional cloning or marker-assisted selection.