Genome-wide association study reveals a NAC transcription factor TaNAC074 linked to pre-harvest sprouting tolerance in wheat.

KEY MESSAGE: Twelve QTL associated with pre-harvest sprouting tolerance were identified using association analysis in wheat. Two markers were validated and a candidate gene TaNAC074 for Qgpf.cas-3B.2 was verified using Agrobacterium-mediated transformation. Pre-harvest sprouting (PHS) is a considerable global threat to wheat yield and quality. Due to this threat, breeders must identify quantitative trait loci (QTL) and genes conferring PHS-tolerance (PHST) to reduce the negative effects of PHS caused by low seed dormancy. In this study, we evaluated a panel of 302 diverse wheat genotypes for PHST in four environments and genotyped the panel with a high-density wheat 660 K SNP array. By using a genome-wide association study (GWAS), we identified 12 stable loci significantly associated with PHST (P < 0.0001), explaining 3.34 - 9.88% of the phenotypic variances. Seven of these loci co-located with QTL and genes reported previously. Five loci (Qgpf.cas-3B.2, Qgpf.cas-3B.3, Qgpf.cas-3B.4, Qgpf.cas-7B.2, and Qgpf.cas-7B.3), located in genomic regions with no known PHST QTL or genes, are likely to be new QTL conferring PHST. Additionally, two molecular markers were developed for Qgpf.cas-3A and Qgpf.cas-7B.3, and validated using a different set of 233 wheat accessions. Finally, the PHST-related function of candidate gene TaNAC074 for Qgpf.cas-3B.2 was confirmed by CAPS (cleaved amplified polymorphic sequences) marker association analysis in 233 wheat accessions and by expression and phenotypic analysis of transgenic wheat. Overexpression of TaNAC074 significantly reduced seed dormancy in wheat. This study contributes to broaden the genetic basis and molecular marker-assisted breeding of PHST.

Genetic dissection of top three leaf traits in rice using progenies from a japonica × indica cross.

The size of the top three leaves of rice plants is strongly associated with yield; thus, it is important to consider quantitative traits representing leaf size (e.g., length and width) when breeding novel rice varieties. It is challenging to measure such traits on a large scale in the field, and little is known about the genetic factors that determine the size of the top three leaves. In the present study, a population of recombinant inbred lines (RILs) and reciprocal single chromosomal segment substitution lines (SSSLs) derived from the progeny of a japonica Asominori × indica IR24 cross were grown under four diverse environmental conditions. Six morphological traits associated with leaf size were measured, namely length and flag leaf, length and flag, second and third leaves. In the RIL population, 49 QTLs were identified that clustered in 30 genomic region. Twenty-three of these QTLs were confirmed in the SSSL population. A comparison with previously reported genes/QTLs revealed eight novel genomic regions that contained uncharacterized ORFs associated with leaf size. The QTLs identified in this study can be used for marker-assisted breeding and for fine mapping of novel genetic elements controlling leaf size in rice.

Genetic dissection on rice grain shape by the two-dimensional image analysis in one japonica × indica population consisting of recombinant inbred lines.

KEY MESSAGE: This article used seven characters from the 2D image analysis to dissect the genetic architecture underlying rice grain shape in one japonica × indica population consisting of 215 recombinant inbred lines. Two-dimensional (2D) digital image analysis is efficient for investigating the rice grain shape characters in large genetic and breeding populations. In this study, we used 2D image analysis to investigate seven characters, i.e., grain length (GL), grain width (GW), length-to-width ratio (LW), grain area (GA), grain circumference (GC), grain diameter (GD), and grain roundness (GR), in one japonica × indica genetic population consisting of 215 recombinant inbred lines. GL and GW can be recorded manually as well, and have been extensively used together with LW (i.e., GL/GW) in genetic studies on grain shape. GC and GA can be hardly measured manually, and have not been used together with GD and GR. Results indicated that the seven characters could be precisely measured by 2D image analysis, genotype by environment interaction was low, and heritability was high. Each character was controlled by a few major stable genes and multiple minor additive genes. A total of 51 QTL were detected for the seven characters across four diverse environments, 22 from GL, GW, and LW, the three traditional characters, and 29 from the other four characters. The 51 QTL were clustered in eighteen marker intervals. Comparing with previous studies and analyzing the stability of identified QTL, we found six non-reported marker intervals, one each on chromosomes 2 and 3, and two each on chromosomes 6 and 8. The newly identified loci and the large-scale phenotyping system would greatly improve our knowledge about the genetic architecture and the future rice breeding on grain shape.

Innovative incentives can sustainably enhance the achievement of straw burning control in China.

With the raising awareness of environmental protection, straw burning ban has been implemented to control straw burning phenomenon in China. It has received significant achievement by reducing the fire spots remarkably, but fire spots still cannot be eliminated in farmland. Although considerable papers and reviews on straw burning have been conducted, there is still a lack of comprehensive and systematic review of exploring the status, obstacles, implications, and motivations of this phenomenon, especially revealing the unique circumstance and experience in China. The review first summarizes the reasons as well as hazards of straw burning in China, and then explores the dilemma of straw burning ban in terms of farmers' endowments. And then, the review discusses the limitations of subsidy from financial expenditure and suggests two alternative innovative incentives: transferred payment from stakeholders and carbon trading. It is hoped that policy suggestion about straw burning and innovative incentives can enlighten researchers and policymakers who intend to implement straw burning ban effectively in the future.

Opportunities for centralized regional mode of manure and sewage management in pig farming: The evidence from environmental and economic performance.

Pig breeding is moving toward more intensive development and is accompanied by the integrated generation of pig waste. This has disrupted the synergy between the original manure and sewage management mode and corresponding farmland at the household level. Centralized bio-energy mode is proposed to relieve environmental pressure, increase the resource recovery efficiency and rebuild the breeding and cropping. However, there is a lack of comprehensive information on a regional scale, particularly regarding evaluation, applicability and feasibility. Therefore, compared to the individual and traditional mode at the household level, this study was conducted using life cycle assessment and life cycle cost analysis, systematically assessed the environmental performance and economic viability of the centralized bio-energy mode at the regional scale, and further explored the adaptability of multi-subjects (various pig farms and biogas enterprise) and regional feasibility. Results revealed that the centralized bio-energy mode appeared to be a better alternative in terms of global warming, terrestrial acidification and marine eutrophication, with the significant reductions of 49.49 %, 6.8 % and 4.67 % respectively. Moreover, the study demonstrated a substantial profit of 48.5 CNY1 per ton of managed pig waste. Furthermore, both environmental and economic performance could be improved through scale expansion and transport optimization, with an optimal collection radius of less than 31.45 km. Conclusions clarified the potential of centralized bio-energy mode and provided valuable references for its implementation in various regions. Ultimately, further contributing to a more efficient, cost-effective, and regulated manner for resource recovery, culminating in the sustainability of pig farming and achieving environmental-friendly agriculture practices in regional contexts.

Genetic basis of geographical differentiation and breeding selection for wheat plant architecture traits.

BACKGROUND: Plant architecture associated with increased grain yield and adaptation to the local environments is selected during wheat (Triticum aestivum) breeding. The internode length of individual stems and tiller length of individual plants are important for the determination of plant architecture. However, few studies have explored the genetic basis of these traits. RESULTS: Here, we conduct a genome-wide association study (GWAS) to dissect the genetic basis of geographical differentiation of these traits in 306 worldwide wheat accessions including both landraces and traditional varieties. We determine the changes of haplotypes for the associated genomic regions in frequency in 831 wheat accessions that are either introduced from other countries or developed in China from last two decades. We identify 83 loci that are associated with one trait, while the remaining 247 loci are pleiotropic. We also find 163 associated loci are under strong selective sweep. GWAS results demonstrate independent regulation of internode length of individual stems and consistent regulation of tiller length of individual plants. This makes it possible to obtain ideal haplotype combinations of the length of four internodes. We also find that the geographical distribution of the haplotypes explains the observed differences in internode length among the worldwide wheat accessions. CONCLUSION: This study provides insights into the genetic basis of plant architecture. It will facilitate gene functional analysis and molecular design of plant architecture for breeding.

Population genomics unravels the Holocene history of bread wheat and its relatives.

Deep knowledge of crop biodiversity is essential to improving global food security. Despite bread wheat serving as a keystone crop worldwide, the population history of bread wheat and its relatives, both cultivated and wild, remains elusive. By analysing whole-genome sequences of 795 wheat accessions, we found that bread wheat originated from the southwest coast of the Caspian Sea and underwent a slow speciation process, lasting ~3,300 yr owing to persistent gene flow from its relatives. Soon after, bread wheat spread across Eurasia and reached Europe, South Asia and East Asia ~7,000 to ~5,000 yr ago, shaping a diversified but occasionally convergent adaptive landscape in novel environments. By contrast, the cultivated relatives of bread wheat experienced a population decline by ~82% over the past ~2,000 yr due to the food choice shift of humans. Further biogeographical modelling predicted a continued population shrinking of many bread wheat relatives in the coming decades because of their vulnerability to the changing climate. These findings will guide future efforts in protecting and utilizing wheat biodiversity to enhance global wheat production.

A high-resolution genotype-phenotype map identifies the TaSPL17 controlling grain number and size in wheat.

BACKGROUND: Large-scale genotype-phenotype association studies of crop germplasm are important for identifying alleles associated with favorable traits. The limited number of single-nucleotide polymorphisms (SNPs) in most wheat genome-wide association studies (GWASs) restricts their power to detect marker-trait associations. Additionally, only a few genes regulating grain number per spikelet have been reported due to sensitivity of this trait to variable environments. RESULTS: We perform a large-scale GWAS using approximately 40 million filtered SNPs for 27 spike morphology traits. We detect 132,086 significant marker-trait associations and the associated SNP markers are located within 590 associated peaks. We detect additional and stronger peaks by dividing spike morphology into sub-traits relative to GWAS results of spike morphology traits. We propose that the genetic dissection of spike morphology is a powerful strategy to detect signals for grain yield traits in wheat. The GWAS results reveal that TaSPL17 positively controls grain size and number by regulating spikelet and floret meristem development, which in turn leads to enhanced grain yield per plant. The haplotypes at TaSPL17 indicate geographical differentiation, domestication effects, and breeding selection. CONCLUSION: Our study provides valuable resources for genetic improvement of spike morphology and a fast-forward genetic solution for candidate gene detection and cloning in wheat.

Identification of Indica rice chromosome segments for the improvement of Japonica inbreds and hybrids.

Exploitation of heterosis has brought significant advance in plant breeding and agricultural production, although its genetic basis is still poorly understood. In this study, a total of 66 chromosome segment substitution (CSS) lines, derived from a cross between japonica rice inbred line Asominori (as the recurrent parent) and indica rice inbred line IR24 (as the donor parent), were used to investigate the genetic basis of heterosis in indica × japonica inter-subspecific rice hybrids. Each CSS line was crossed with the background parent Asominori, and the heterosis of F(1) hybrids was estimated by comparing the F(1) performance with its two parental lines. Field experiments were carried out across six different environments to evaluate yield and yield-related traits in the 66 CSS lines and their 66 corresponding F(1) hybrids. Quantitative trait loci (QTL) analyses were conducted using a likelihood ratio test based on the stepwise regression. Thirty-six QTL were identified with significant effects in CSSL, 21 with significant effects in hybrids and 13 with significant effects in both. On the basis of average dominance degree, of all the 70 QTL affecting yield-related agronomic traits, 28.6% (20) showed an overdominance, 35.7% (25) a partial dominance and 30% (21) an additive effect, indicating that all effects contribute to trait variation in japonica-indica rice hybrids. Effects of these QTL were examined to identify Indica rice chromosome segments of interest for the improvement of japonica inbred lines and hybrids.

Sustainable Management of Food Waste during COVID-19 Pandemic: Insights into Irrational Food Hoarding among Chinese Citizens.

During the COVID-19 pandemic, food waste caused by excessive hoarding has accounted a large proportion of the total food waste in urban Chinese households, which indicates that reducing food hoarding has become key to managing household food waste. This study therefore explored the behavioral mechanisms underlying excessive food hoarding among citizens. Based on a sample set of 511 respondents surveyed in Beijing, Hefei, and Guiyang in July 2022, a PLS-SEM model was conducted using SmartPLS 3.0 software to simulate the decision-making process of food hoarding. The following results were found. First, among the households with hoarding, 66.37% had some degree of food waste. Second, hoarding preference was the direct predictor of hoarding behavior, which means that hoarding behavior can be effectively controlled by regulating preferences. Third, group influence including homology consistency and social network support, as well as psychological panic, both enhanced citizens' hoarding preference and induced hoarding behavior. Therefore, it is necessary to weaken group influence and try to help citizens overcome panic. Finally, food supply information release can not only alleviate citizens' psychological panic and weaken group influence, but also block the transformation of preference into behavior. The above results are of great importance for the design of management policies for food waste caused by irrational hoarding during the pandemic.

Recognition on characteristics and applicability of typical modes for manure & sewage management in pig farming: A case study in Hebei, China.

Scale-up intensive pig farming can increase profitability by economies of large scale, but it also exacerbates environmental pollution caused by the disordered discharge of manure and sewage. Manure & sewage management (MSM) is critical to mitigate environmental pressure and reuse livestock waste. However, the corresponding MSM measures adopted by pig farmers are multitudinous in reality, due to the diversity of MSM methods and heterogeneity of farmers' characteristics and behaviors. Thus, this study empirically categorized five typical MSM modes (i.e., traditional simple mode (TSM), mixed processing mode (MPM), semi-biogas mode (SBM), professional processing with simple utilization mode (PPSUM) and professional processing with full utilization mode (PPFUM)) by clustering analysis, based on the field data from 406 pig farms, and further discriminated farmers' heterogeneous characteristics on corresponding mode adoption. Results revealed that each mode was distinctive. The applicability of the corresponding mode was reflected in the synthesis deliberation, involving farming structure, land, farmers' characteristic and their subjective awareness. Farmers' education level and pro-environmental perception are significantly promoted to adopt technology-intensive MSM modes. Scale upgrading has a positive effect on mechanization adoption and diversified strategies application. Land as an unalterable objective factor restricted the extension of MSM modes based on field returning. Conclusions clarified typical MSM modes and provided references to individual pig farms on appropriate mode selection, further enhancing the efficiency of MSM and contributing to the sustainability of green development of pig farming in China.

The influence of smartphone use on conservation agricultural practice: Evidence from the extension of rice-green manure rotation system in China.

Although the impact of smartphone use has aroused widespread public interest, its effect on promoting conservation agriculture has never been revealed. We developed an integrated model to explain the scientific question of how smartphone use influence farmers' behavior of adopting a conservation agricultural practice-rice-green manure rotation system (RGRS). Based on a sample set containing 934 respondents, the causal chain was estimated by using the PLS-SEM with bootstrapping. The results showed that smartphone use directly contributes to farmers' RGRS adoption behavior, which provides new evidence for promoting the popularization of intelligent terminals in rural China. Another finding was that, perceived environmental degradation threats and environmental services of RGRS mediated the relationship between smartphone use and farmers' adoption behavior. This discovery provides us with enlightenment that knowledge related to environmental degradation and environmental services of RGRS can be imported into smartphone Apps commonly used by farmers to increase information exposure, raise environmental awareness and regulate farmer behavior. Besides, smartphone use reduced farmers' satisfaction with governmental support for RGRS, which adversely affected farmers' RGRS adoption behavior. Surprisingly, we found that the use of some traditional media helped to improve farmers' satisfaction. Therefore, policymakers should not ignore the role of traditional media while making use of smartphone-based information tools. These results can help policymakers better understand the contribution of smartphone use to conservation agriculture, and inform the development of supportive policies.

The potential of dairy manure and sewage management pathways towards a circular economy: A meta-analysis from the life cycle perspective.

The global dairy farming sector has markedly expanded and intensified over the past decades due to the growing demand for milk and dairy products. The interest in implementing life cycle assessments of various manure and sewage management (MSM) strategies is increasing on a global scale, which is motivated by the concerns of environmental degradation caused by unsustainable MSM and growing awareness of circular economy. Life cycle thinking concept has been widely introduced to favor the comparative studies of different MSM strategies, with the aim of identifying suitable MSM strategies and formulating related policies. This meta-analysis presented comparative results of publicly available dairy MSM pathways, including waste-to-energy, composting, recycling, and other management pathways, aiming to explore potential benefits towards a circular economy. Results showed a consensus that waste-to-energy pathway significantly reduced global warming, eutrophication, and ecotoxicity potential. More specifically, the comparative performances of various detailed technologies belonging to a specified pathway were analyzed. Results indicated that anaerobic mono-digestion decreased global warming and eutrophication remarkably; its integrated management technologies reduced global warming considerably and an obvious decrease in eutrophication potential was observed. It revealed that most of current MSM strategies had limited potential and uncertain consequences to reduce environmental impacts and costs. In terms of influence factors, besides the intrinsic factor (pathway type), key extrinsic determinants including location, country income level, and farm scale were proved to affect mitigation potential of some specific impacts. Overall, it is necessary for the scientific community and policy-makers to focus on more possible trade-offs of different life cycle performances towards sustainability and circularity.

Wheat speciation and adaptation: perspectives from reticulate evolution.

Reticulate evolution through the interchanging of genetic components across organisms can impact significantly on the fitness and adaptation of species. Bread wheat (Triticum aestivum subsp. aestivum) is one of the most important crops in the world. Allopolyploid speciation, frequent hybridization, extensive introgression, and occasional horizontal gene transfer (HGT) have been shaping a typical paradigm of reticulate evolution in bread wheat and its wild relatives, which is likely to have a substantial influence on phenotypic traits and environmental adaptability of bread wheat. In this review, we outlined the evolutionary history of bread wheat and its wild relatives with a highlight on the interspecific hybridization events, demonstrating the reticulate relationship between species/subspecies in the genera Triticum and Aegilops. Furthermore, we discussed the genetic mechanisms and evolutionary significance underlying the introgression of bread wheat and its wild relatives. An in-depth understanding of the evolutionary process of Triticum species should be beneficial to future genetic study and breeding of bread wheat.

Circular RNA circ_0091579 Promotes Hepatocellular Carcinoma Proliferation, Migration, Invasion, and Glycolysis Through miR-490-5p/CASC3 Axis.

Background: Hepatocellular carcinoma (HCC) is one of the most common malignancies with high invasion and metastasis capacities. Circular RNAs (circRNAs) were evidenced to take part in the progression of multifarious cancers, including HCC. However, the role of circ_0091579 in HCC progression has not been fully described. This study aimed to explore the function of circ_0091579 and its potential regulatory mechanism in the progression of HCC. Materials and Methods: The expression of circ_0091579, microRNA-490-5p (miR-490-5p), and cancer susceptibility candidate 3 (CASC3) in HCC tissues and cells was detected by quantitative real-time polymerase chain reaction. The circular characteristic and stability of circ_0091579 were verified by RNase R digestion and actinomycin D reaction assays. Cell proliferation, migration, and invasion were determined by methyl thiazolyl tetrazolium assay and Transwell assay, respectively. The level of glycolysis was evaluated by glucose consumption and lactate production. The levels of proteins were examined by Western blot. The interaction between miR-490-5p and circ_0091579 or CASC3 was certified by Dual-luciferase reporter assay. Results: circ_0091579 and CASC3 were upregulated, while miR-490-5p was downregulated in HCC tissues and cells. Silencing of either circ_0091579 or CASC3 suppressed cell proliferation, migration, invasion, and glycolysis in HCC cells. Moreover, miR-490-5p was verified to directly bind to circ_0091579 and CASC3. Circ_0091579 upregulated CASC3 by sponging miR-490-5p in HCC cells to promote cell proliferation, invasion, and migration. Conclusion: circ_0091579 promoted cell proliferation, migration, invasion, and glycolysis partially through miR-490-5p/CASC3 axis in HCC cells.

Environmental Behavior Spillover or Public Information Induction: Consumers' Intention to Pay a Premium for Rice Grown with Green Manure as Crop Fertilizer.

Nowadays, there is a growing interest in pro-environmental foods produced by pro-environmental practices. However, consumers' payment motivations towards such foods are currently poorly understood. This manuscript provided a critical investigation of Chinese consumers' intention to pay a premium (ITPP) for rice grown with green manure as crop fertilizer (GMR). One focus was the establishment of an explanatory structural research framework that includes effects of environmental behavior spillover (EBS) and public information induction (PII); another focus was to analyze the impacts of the selected structural elements on ITPP by introducing education as a moderator. Results suggest that consumers' ITPP can be largely influenced by PII, therefore, for GMR marketers and policy makers, measures should be developed to widen consumers' access to public information related to GMR and to improve their capacity of screening effective information. EBS, when ITPP remains low, emerged as a pivotal predictor of consumers' ITPP. This observation provides us with the enlightenment that breeding consumers' daily environmental behaviors is highly valued to inspire their payment intention in the early stages of GMR market development. Another finding is that, with the introduction of the educational variable, the influence coefficients of EBS and PII on ITPP increased from 0.42 and 0.53 to 0.61 and 0.66, respectively, which means that it is possible to boost consumers' payment intention by improving their educational attainment. This study contributes to the existing literature by providing empirical evidence for the GMR industrial upgrading strategy and have significant implications for the environmental governance of the agricultural sector.

Identifying key pathways in manure and sewage management of dairy farming based on a quantitative typology: A case study in China.

With the greatly increased demand for animal products, the global dairy sector has experienced rapid expansion and intensification. The correspondingly increasing manure and sewage produced has been the major contributor to environmental burden and human health, especially in developing countries like China. Both worldwide environmental concerns and growing awareness of the circular economy have focused the governments' attention on environmental policies related to sustainable manure and sewage management (MSM). However, inherently dynamic decision-making processes of individual farms result in a great diversity of MSM practices, which leads to enormous difficulties and complexity in further sustainability and policy evaluation. Hence, it is essential to explore the key MSM pathways to represent diversity at a scientific and statistic view. While it is rarely practiced, particularly in China's dairy farming. We used China as a case study to develop the key MSM pathways using data from the nationwide survey of 306 scale dairy farms via a quantitative typology methodology. The results by optimal clustering solution revealed four key pathways based on the individual practices which are associated with the collection, storage, and processing and utilization stages. Furthermore, general characteristics were compared to identify potential determinant factors. It revealed that the major indicators such as resource endowments, milk productivity and quality, and revenues and expenditure showed a consistently increasing trend among pathways. The results indicated resource availability and intensive degree, to a certain extent, affected the farmers' selection. The possibilities of performing sustainability and policy evaluation at a higher scale were also demonstrated. Overall, the identified key pathways can help to know regional waste utilization and economic potential to evolve their MSM strategies. They are especially critical for developing countries to obtain typical MSM profiles and formulate targeted policies more effectively, aiming to promote dairy sustainable development and achieve the circular economy globally.

Incentive mechanism to promote corn stalk return sustainably in Henan, China.

Corn stalk return (CSR) can manage agricultural residues on the spot to avoid field open burning and protect the environment. However, the implementation of this measure encounters reluctance from farmers which hinders its sustainability. This study combined the economic (cost) and technical (return amount, crushing quality, and decomposition of corn stalk) aspects to examine the factors affecting farmers' willingness to participate in the CSR by using a logistic regression model. The level of willingness to accept (WTA) compensation and its determinants were analyzed by using a tobit model. Based on the survey of 925 farmers, this study found the likelihood of farmers' participation in CSR will be decreased when CSR has high machinery cost, an excessive amount of stalk, poor quality of crushing, and slow decomposing rate. The farmers' WTA for CSR was estimated at about 711 Chinese Yuan (RMB) per ha annually, much higher than the current compensation level of 75-225 RMB per ha in Henan. Farmers were willing to be compensated more because of the high cost and slow decomposing rate. The issues in economic and technical sides should attract more attention, and the compensation should be increased and the technical problems should be solved to stimulate farmers' willingness of CSR. By providing a fuller understanding of farmers' CSR behavior, this study can serve as a reference for the Chinese government to develop and implement better policies.

Nutritional quality and health risks of wheat grains from organic and conventional cropping systems.

The influence of cropping systems on nutrition and food safety is controversial. This study aimed to evaluate the effects of an organic cropping system (OCS) on wheat nutrition and food safety at the molecular level by using a comprehensive research method. Nutrient deviation in samples from an OCS and a conventional cropping system (CCS) were detected, and 58 biomarkers were selected through multivariate statistical analysis and were further qualitatively and quantitatively analyzed. The health risk of heavy metal(loid)s (HMs) for different populations was assessed based on the estimated average daily dose and recommended ingestion reference dose, which indicated that populations ingesting grains from OCSs had higher non-carcinogenic and carcinogenic risks. Additionally, HMs posed greater non-carcinogenic risks to children under five years old and greater carcinogenic risks to adults.This study highlights the need to consider the potential risk from HMs and nutritive ingredient differences in organic food.

Triticum population sequencing provides insights into wheat adaptation.

Bread wheat expanded its habitat from a core area of the Fertile Crescent to global environments within ~10,000 years. The genetic mechanisms of this remarkable evolutionary success are not well understood. By whole-genome sequencing of populations from 25 subspecies within the genera Triticum and Aegilops, we identified composite introgression from wild populations contributing to a substantial portion (4-32%) of the bread wheat genome, which increased the genetic diversity of bread wheat and allowed its divergent adaptation. Meanwhile, convergent adaptation to human selection showed 2- to 16-fold enrichment relative to random expectation-a certain set of genes were repeatedly selected in Triticum species despite their drastic differences in ploidy levels and growing zones, indicating the important role of evolutionary constraints in shaping the adaptive landscape of bread wheat. These results showed the genetic necessities of wheat as a global crop and provided new perspectives on transferring adaptive success across species for crop improvement.