成都师范学院

[Objective]As a critical component of wheat grains,the embryo is closely correlated to nutritional value,germination,and seedling establishment.Mining embryo size loci from genetically diverse Chinese wheat landraces and deciphering their genetic effects will enhance our understanding of the genetic basis of embryo size and provide molecular targets for future breeding programs.[Method]We genotyped 240 Chinese wheat landraces using the 660K SNP array and performed genome-wide association studies(GWAS)via a mixed linear model,integrating embryo size phenotypic data across three environments.Significant loci were subjected to genetic effect analysis and candidate gene prediction.[Result]Phenotypic variation ranges across environments and BLUP values were:embryo length(1.64-3.43 mm),width(0.93-2.58 mm),area(1.10-5.71 mm2),and length-to-width ratio(1.06-2.08),with broad-sense heritabilities of 0.76,0.47,0.54,and 0.60,respectively.Significant positive correlations(r=0.271-0.922)existed among embryo traits,and between major embryo traits(length,width,area)and grain length or thousand-kernel weight.A total of 18 stable SNP loci significantly associated with embryo length and area were identified across two environments and BLUP values,which were clustered into four quantitative trait locus(QTL)intervals.These included three QTLs for embryo length and one for embryo area,with colocalization observed between QEA.sicau.3B and QEL.sicau.3B.2.For the major QTL QEL.sicau.1B,we predicted nine candidate genes.Genetic effect analysis revealed that the increasing allele of QEL.sicau.1B significantly enhanced embryo length,grain length and width,thousand-kernel weight,and reduced flowering time,while demonstrating superior effects on seedling root dry weight and shoot biomass,albeit with minor negative impacts on tiller number and spikelet number.Comparative analysis suggested both QEL.sicau.1B and QEL.sicau.3B.2 represent novel loci.[Conclusion]GWAS identified four stable loci significantly associated with embryo size,among which nine potential candidate genes were predicted for the major embryo-length QTL(QEL.sicau.1B).The study demonstrated significant positive correlations between embryo size and grain dimensions,and revealed a functional association with seedling root vigor.

To improve the functional properties of Rosa roxburghii Tratt. polysaccharide (RTFP), this study prepared crude polysaccharides (RTFP-40, RTFP-60) using water extraction, which were then separated, purified, and chemically modified to obtain sulfated polysaccharides (S-RTFP-40, S-RTFP-60) and phosphorylated polysaccharides (P-RTFP-40, P-RTFP-60). The effects of chemical modification on their structure and bioactivity were explored through in vitro antioxidant and hypoglycemic experiments. The results showed that both modifications could significantly alter the triple-helix structure of the RTFP-40 and RTFP-60 extracts and introduce sulfate and phosphate groups into the polysaccharide structure. Both modifications significantly improved the in vitro hypoglycemic ability of Rosa roxburghii polysaccharides, with the GDRI indices of S-RTFP-60 and P-RTFP-60 increasing by 8.27% and 3.73%, respectively. All four derivatives enhanced the inhibitory effect on α-amylase, with S-RTFP-40 and S-RTFP-60 increasing it by 15.19% and 41.53%, respectively. Excessive phosphorylation had a negative effect on antioxidant activity. Comparatively, sulfation was more effective than phosphorylation in enhancing both antioxidant and hypoglycemic activities of the polysaccharides, with S-RTFP-60 showing a notable increase in vitro hypoglycemic activity. In summary, sulfation modification is suitable for improving the hypoglycemic activity of Rosa roxburghii polysaccharides.

Encouraging and fostering entrepreneurship at the Bottom of the Pyramid(BOP)has emerged in recent years as a novel approach to achieving sustainable poverty alleviation and effective rural revitalization.However,to date,cognitive factors influencing the entrepreneurial behavior of BOP populations have received scant attention.Anchored in scarcity theory,this study addresses the core research question:does a poverty mindset constrain entrepreneurial ideation?Through three key research modules,it investigates the relationship between poverty mindset and entrepreneurial ideation in the BOP entrepreneurial context:1)The process mechanism of how poverty mindset influences entrepreneurial ideation from an implicit cognition perspective;2)Intervention strategies for mitigating poverty mindset's impact on entrepreneurial ideation from a constructivist perspective;3)The profile of poverty mindset and its predictive effects from a self-regulation perspective under scarcity.Employing a multi-perspective systematic research design,this study aims to uncover the developmental patterns of the poverty mindset-entrepreneurial ideation relationship within the indigenous BOP entrepreneurial context.The findings will deepen theoretical understanding of the early-stage innovation activities of BOP entrepreneurs driven by situational-cognitive factors,while providing theoretical guidance and practical insights for policymakers and practitioners in designing targeted entrepreneurial support policies and knowledge services for BOP populations.