Dynamic impact of delivery modes on gut microbiota in preterm infants hospitalized during the initial 4 weeks of life.

Preterm infants face a high risk of various complications, and their gut microbiota plays a pivotal role in health. Delivery modes have been reported to affect the development of gut microbiota in term infants, but its impact on preterm infants remains unclear. Here, we collected fecal samples from 30 preterm infants at five-time points within the first four weeks of life. Employing 16 S rRNA sequencing, principal coordinates analysis, the analysis of similarities, and the Wilcoxon rank-sum test, we examined the top dominant phyla and genera, the temporal changes in specific taxa abundance, and their relationship with delivery modes, such as Escherichia-Shigella and Enterococcus based on vaginal delivery and Pluralibacter related to cesarean section. Moreover, we identified particular bacteria, such as Taonella, Patulibacter, and others, whose proportions fluctuated among preterm infants born via different delivery modes at varying time points, as well as the microbiota types and functions. These results indicated the influence of delivery mode on the composition and function of the preterm infant gut microbiota. Importantly, these effects are time-dependent during the early stages of life. These insights shed light on the pivotal role of delivery mode in shaping the gut microbiota of preterm infants and have significant clinical implications for their care and management.

Discrepancies in resistant starch and starch physicochemical properties between rice mutants similar in high amylose content.

The content of resistant starch (RS) was considered positively correlated with the apparent amylose content (AAC). Here, we analyzed two Indica rice mutants, RS111 and Zhedagaozhi 1B, similar in high AAC and found that their RS content differed remarkably. RS111 had higher RS3 content but lower RS2 content than Zhedagaozhi 1B; correspondingly, cooked RS111 showed slower digestibility. RS111 had smaller irregular and oval starch granules when compared with Zhedagaozhi 1B and the wild type. Zhedagaozhi 1B showed a B-type starch pattern, different from RS111 and the wild type, which showed A-type starch. Meantime, RS111 had more fa and fb1 but less fb3 than Zhedagaozhi 1B. Both mutants showed decreased viscosity and swelling power when compared with the parents. RS111 had the lowest viscosity, and Zhedagaozhi 1B had the smallest swelling power. The different fine structures of amylopectin between RS111 and Zhedagaozhi 1B led to different starch types, gelatinization properties, paste viscosity, and digestibility. In addition to enhancing amylose content, modifications on amylopectin structure showed great potent in breeding rice with different RS2 and RS3 content, which could meet the increasing needs for various rice germplasms.

Examination of the mechanism of Piezo ion channel in 5-HT synthesis in the enterochromaffin cell and its association with gut motility.

In the gastrointestinal tract, serotonin (5-hydroxytryptamine, 5-HT) is an important monoamine that regulates intestinal dynamics. QGP-1 cells are human-derived enterochromaffin cells that secrete 5-HT and functionally express Piezo ion channels associated with cellular mechanosensation. Piezo ion channels can be blocked by Grammostola spatulata mechanotoxin 4 (GsMTx4), a spider venom peptide that inhibits cationic mechanosensitive channels. The primary aim of this study was to explore the effects of GsMTx4 on 5-HT secretion in QGP-1 cells in vitro. We investigated the transcript and protein levels of the Piezo1/2 ion channel, tryptophan hydroxylase 1 (TPH1), and mitogen-activated protein kinase signaling pathways. In addition, we observed that GsMTx4 affected mouse intestinal motility in vivo. Furthermore, GsMTx4 blocked the response of QGP-1 cells to ultrasound, a mechanical stimulus.The prolonged presence of GsMTx4 increased the 5-HT levels in the QGP-1 cell culture system, whereas Piezo1/2 expression decreased, and TPH1 expression increased. This effect was accompanied by the increased phosphorylation of the p38 protein. GsMTx4 increased the entire intestinal passage time of carmine without altering intestinal inflammation. Taken together, inhibition of Piezo1/2 can mediate an increase in 5-HT, which is associated with TPH1, a key enzyme for 5-HT synthesis. It is also accompanied by the activation of the p38 signaling pathway. Inhibitors of Piezo1/2 can modulate 5-HT secretion and influence intestinal motility.

Early life stress induces irritable bowel syndrome from childhood to adulthood in mice.

Background: Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal disorder. Traditionally, early life stress (ELS) is predisposed to IBS in adult. However, whether ELS induces IBS in early life remains unclear. Methods: Separated cohort studies were conducted in neonatal male pups of C57BL/6 mice by maternal separation (MS) model. MS and non-separation mice were scheduled to be evaluated for prime IBS-phenotypes, including visceral hypersensitivity, intestinal motility, intestinal permeability, and anxiety-like behavior. Ileal contents and fecal samples were collected and analyzed by 16S rRNA gene sequencing and bacterial community analyses. Subcellular structures of intestinal epithelial, such as epithelial tight junctions and mitochondria, were observed under transmission electron microscopy. Results: MS induced visceral hypersensitivity and decreased total intestinal transit time from childhood to adulthood. In addition, MS induced intestinal hyperpermeability and anxiety-like behavior from adolescence to adulthood. Besides, MS affected intestinal microbial composition from childhood to adulthood. Moreover, MS disrupted intestinal mitochondrial structure from childhood to adulthood. Conclusion: The study showed for the first time that MS induced IBS from early life to adulthood in mice. The disrupted intestinal mitochondrial structure and the significant dysbiosis of intestinal microbiota in early life may contribute to the initiation and progress of IBS from early life to adulthood.

Lipid complexation reduces rice starch digestibility and boosts short-chain fatty acid production via gut microbiota.

In this study, two rice varieties (RS4 and GZ93) with different amylose and lipid contents were studied, and their starch was used to prepare starch-palmitic acid complexes. The RS4 samples showed a significantly higher lipid content in their flour, starch, and complex samples compared to GZ93. The static in vitro digestion highlighted that RS4 samples had significantly lower digestibility than the GZ93 samples. The C∞ of the starch-lipid complex samples was found to be 17.7% and 18.5% lower than that of the starch samples in GZ93 and RS4, respectively. The INFOGEST undigested fractions were subsequently used for in vitro colonic fermentation. Short-chain fatty acids (SCFAs) concentrations, mainly acetate, and propionate were significantly higher in starch-lipid complexes compared to native flour or starch samples. Starch-lipid complexes produced a distinctive microbial composition, which resulted in different gene functions, mainly related to pyruvate, fructose, and mannose metabolism. Using Model-based Integration of Metabolite Observations and Species Abundances 2 (MIMOSA2), SCFA production was predicted and associated with the gut microbiota. These results indicated that incorporating lipids into rice starch promotes SCFA production by modulating the gut microbiota selectively.

Handling multi-objective optimization problems with a comprehensive indicator and layered particle swarm optimizer.

The multi-objective particle swarm optimization algorithm has several drawbacks, such as premature convergence, inadequate convergence, and inadequate diversity. This is particularly true for complex, high-dimensional, multi-objective problems, where it is easy to fall into a local optimum. To address these issues, this paper proposes a novel algorithm called IMOPSOCE. The innovations for the proposed algorithm mainly contain three crucial factors: 1) an external archive maintenance strategy based on the inflection point distance and distribution coefficient is designed, and the comprehensive indicator (CM) is used to remove the non-dominated solutions with poor comprehensive performance to improve the convergence of the algorithm and diversity of the swarm; 2) using the random inertia weight strategy to efficiently control the movement of particles, balance the exploration and exploitation capabilities of the swarm, and avoid excessive local and global searches; and 3) offering different flight modes for particles at different levels after each update to further enhance the optimization capacity. Finally, the algorithm is tested on 22 typical test functions and compared with 10 other algorithms, demonstrating its competitiveness and outperformance on the majority of test functions.

Alterations in the Fecal Microbiota Composition in Pediatric Acute Diarrhea: A Cross-Sectional and Comparative Study of Viral and Bacterial Enteritis.

Objective: To examine the association between the fecal microbiota of acute diarrhea in children and provide gut microbiota information related the acute diarrhea with rotavirus. Patients and Methods: Children with acute diarrhea aged 3-60 months were selected for the study. Routine stool examination was performed, and stool samples were collected and stored at -80 °C until further analysis. Fecal microbial DNA was extracted, and DNA concentration and quality were detected. PCR amplification and 16S rDNA high-throughput sequencing analysis using the Illumina MiSeq platform were performed, and intestinal flora was statistically analyzed. Results: Children with acute diarrhea exhibited gut microbial dysbiosis. Lower microbial diversity and richness were observed in the viral enteritis and bacterial enteritis groups than in the control group. Composition of the microbiota in acute diarrhea differed from that in the control group. The Bacteroidetes/Firmicutes dramatically decreased in the viral enteritis and bacterial enteritis groups. However, the relative abundance of Proteobacteria and Fusobacteria increased, especially in the bacterial enteritis group. In addition, the relative abundance of Actinobacteria had dramatically increased in the viral enteritis group. According to the Kyoto Encyclopedia of Genes and Genomes map analysis, the membrane transport dysfunction was caused by rotavirus infection, while the membrane transport dysfunction was more evident in bacterial infection. Conclusion: Acute diarrhea infections cause fecal microbiota dysbiosis in children. Changes in fecal microflora in children suggest that the regulation of intestinal flora in children with acute diarrhea should be strengthened.

Comparative studies on physicochemical properties of three potato varieties different in RS2 and RS3 contents.

BACKGROUND: At present, increasing importance has been attracted to healthy food enriched in resistant starch (RS), which has great benefits in health-promoting. Raw potato has rich RS2, whereas most RS2 may become digestible after gelatinization, resulting in few RS being left in processed potato. Breeding potatoes with high RS2 or RS3 or both can meet the demand for various healthy potato products. RESULTS: There were apparent discrepancies among three potatoes with contrast RS2 and RS3 content in thermal properties, viscosity and digestibility. ZS-5 had the highest RS2 with 50.17% but the lowest RS3 with 3.31%. Meanwhile, ZS-5 had the largest starch granule, the highest proportion of B3, viscosity and hardness, and the highest digestibility. DN303 with the highest content of RS3 (5.08%) had the lowest hardness and fracturability. MG56-42 with both higher RS2 and RS3 content showed the highest resistance to digestion and moderate hardness and fracturability. CONCLUSION: The present study enriches the potential resources and provides a reliable scientific basis for high RS potatoes breeding. The various features of different potatoes make it possible to screen potatoes according to different demands. © 2023 Society of Chemical Industry.

Inactivation of SSIIIa enhances the RS content through altering starch structure and accumulating C18:2 in japonica rice.

SSIIIa was the key gene responsible for RS formation in rice endosperm. The higher RS content in ssIIIa mutant has been proposed to be majorly due to the increased amylose-lipid complexes (RS5). However, the formation of RS5 elicited by ssIIIa mutation and the importance of RS5 for total RS content in rice are still unclear. With japonica ssIIIa loss-of-function mutants created by CRISPR/Cas9 gene editing, the effects of SSIIIa mutation on RS5 were furtherly evaluated through investigating the transcriptome and metabolites. Inactivation of SSIIIa caused significant enhancement in amylose and RS content but without depletion in starch reserves. SSIIIa mutation modulated the genes involved in carbohydrate and lipid metabolisms and the redistribution of substances, led to accumulated protein, glucose, fructose, and C18:2. Besides the increased amylose content and altered amylopectin structure, the increased C18:2 contributed greatly to the enhancement in RS content in japonica ssIIIa mutants through complexing with amylose to form RS5, while the existence of lipid counted against the enhancement of RS content in indica rice. RS5 showed discrepant contributions for the total RS in rice with different genetic background. Inactivation of SSIIIa has great potential in improving RS5 content in japonica rice without great yield loss.

Maternal separation leads to dynamic changes of visceral hypersensitivity and fecal metabolomics from childhood to adulthood.

We assessed dynamic changes in visceral hypersensitivity and fecal metabolomics through a mouse model of irritable bowel syndrome (IBS) from childhood to adulthood. A mouse model of IBS was constructed with maternal separation (MS) in early life. Male mice aged 25, 40, and 70 days were used. Visceral sensitivity was assessed by recording the reaction between the abdominal withdrawal reflex and colorectal distension. Metabolomics was identified and quantified by liquid chromatography-tandem mass spectrometry. The visceral sensitivity of the MS group was significantly higher than that of the non-separation (NS) group in the three age groups. The top four fecal differential metabolites in the different age groups were lipids, lipid molecules, organic heterocyclic compounds, organic acids and derivatives, and benzenoids. Five identical differential metabolites were detected in the feces and ileal contents of the MS and NS groups at different ages, namely, benzamide, taurine, acetyl-L-carnitine, indole, and ethylbenzene. Taurine and hypotaurine metabolism were the most relevant pathways at P25, whereas histidine metabolism was the most relevant pathway at P40 and P70. Visceral hypersensitivity in the MS group lasted from childhood to adulthood. The different metabolites and metabolic pathways detected in MS groups of different ages provide a theoretical basis for IBS pathogenesis.

Loss of function of SSIIIa and SSIIIb coordinately confers high RS content in cooked rice.

The sedentary lifestyle and refined food consumption significantly lead to obesity, type 2 diabetes, and related complications, which have become one of the major threats to global health. This incidence could be potentially reduced by daily foods rich in resistant starch (RS). However, it remains a challenge to breed high-RS rice varieties. Here, we reported a high-RS mutant rs4 with an RS content of ~10.8% in cooked rice. The genetic study revealed that the loss-of-function SSIIIb and SSIIIa together with a strong Wx allele in the background collaboratively contributed to the high-RS phenotype of the rs4 mutant. The increased RS contents in ssIIIa and ssIIIa ssIIIb mutants were associated with the increased amylose and lipid contents. SSIIIb and SSIIIa proteins were functionally redundant, whereas SSIIIb mainly functioned in leaves and SSIIIa largely in endosperm owing to their divergent tissue-specific expression patterns. Furthermore, we found that SSIII experienced duplication in different cereals, of which one SSIII paralog was mainly expressed in leaves and another in the endosperm. SSII but not SSIV showed a similar evolutionary pattern to SSIII. The copies of endosperm-expressed SSIII and SSII were associated with high total starch contents and low RS levels in the seeds of tested cereals, compared with low starch contents and high RS levels in tested dicots. These results provided critical genetic resources for breeding high-RS rice cultivars, and the evolutionary features of these genes may facilitate to generate high-RS varieties in different cereals.

Physicochemical characterizations of five Dioscorea alata L. starches from China.

D. alata is an important edible and medicinal plant in China. Its tuber is rich in starch but the understanding of the physiochemical properties of D. alata starch is limited. In order to explore the processing and application potential of different D. alata accessions in China, five kinds of D. alata starch (LY, WC, XT, GZ, SM) were isolated and characterized. The study showed that D. alata tubers contained abundant starch, enriched in amylose and resistant starch (RS). D. alata starches showed B-type or C-type diffraction pattern, had higher RS content and gelatinization temperature (GT), lower fa and viscosity when compared to D. opposita, D. esculenta, and D. nipponica. Among D. alata starches, D. alata (SM) showing the C-type diffraction pattern, had the lowest proportion of fa with 10.18 %, the highest amylose, RS2 and RS3 content of 40.24 %, 84.17 % and 10.48 % respectively, and the highest GT and viscosity. The results indicated that D. alata tubers are potential sources for novel starch with high amylose and RS content, and provided a theoretical basis for further utilizations of D. alata starch in food processing and industry application.

Deciding Alone or with Others: Employment Anxiety and Social Distance Predict Intuitiveness in Career Decision Making.

Intuitive career decisions can influence people's career choices and subsequent job competencies, which are related to their development and happiness. There is evidence that both anxiety and social distance influence intuitive career decisions individually, but it is unclear how employment anxiety and social distance influence intuitive career decisions individually and how they interact to influence intuitive career decisions. Drawing on the cognitive-emotional dual-system model, in this study, 298 college students and 386 senior job-seeking students were tested through behavioral experiments and questionnaires, respectively. The results showed that employment anxious individuals have a higher intuitive level in career decision making, and they also have a higher intuitive level when making career decisions for others at a far social distance. In addition, employment anxiety and social distance interact to influence the intuitiveness of career decision making. When making career decisions for themselves and those who are close to them, the increase in employment anxiety will increase the intuitive level. Therefore, in a non-anxious situation, you can make career decisions on your own or get help from someone close to you, but in anxious situations, you can turn to others who are at a far social distance to help make decisions.

High temperature boosts resistant starch content by altering starch structure and lipid content in rice ssIIIa mutants.

High temperature (HT) during grain filling had adverse influences on starch synthesis. In this study, the influences of HT on resistant starch (RS) formation in rice were investigated. Most genes in ssIIIa mutants especially in RS4 were upregulated under Normal Temperature (NT) while downregulated under HT when compared with those of wild parent R7954. ssIIIa mutants had higher RS content, more lipid accumulation, higher proportion of short chains of DP 9-15, and less long chains of DP ≥37. ssIIIa mutation exacerbated the influences of HT on starch metabolite and caused larger declines in the expression of BEI, BEIIa, BEIIb, and SSIVb when exposed to HT. HT reduced the contents of total starch and apparent amylose significantly in wild type but not in mutants. Meanwhile, lipids were enriched in all varieties, but the amounts of starch-lipid complexes and the RS content were only heightened in mutants under HT. HT led to greatest declines in the amount of DP 9-15 and increases in the proportion of fb3 (DP ≥37); the declines and increases were all larger in mutants, which resulted in varied starch crystallinity. The increased long-chain amylopectin and lipids may be the major contributor for the elevated RS content in mutants under HT through forming more starch-lipid complexes (RSV).

Pre-soaking treatment can improve cooking quality of high-amylose rice while maintaining its low digestibility.

Rice is a staple food for more than half of the world's population and it is regarded as a high glycemic index (GI) food. Breeders developed high amylose rice having low digestibility, but it also has inferior palatability. This study used high-amylose rice (HAR) produced by gamma irradiation and compared the digestion and physicochemical properties related to palatability with those of low-amylose rice (LAR). Pre-soaking and different-pH treatments were adopted to find a way to enhance the palatability of HAR while maintaining its low digestibility. After pre-soaking, HAR had a higher water uptake ratio (4.68 vs. 4.11 g g-1), proportion of leached starch (16.6 vs. 12.6%) and adhesiveness (77 vs. 39), but lower setback (0.092 vs. 0.107 Pa s), hardness (10.1 vs. 12.6 kg) and resilience (0.20 vs. 0.25). The results showed that pre-soaking was able to enhance the quality of the cooked rice mainly by modifying the starch amorphous region while maintaining the low digestibility of HAR. Pre-soaking can be adopted as a practical and effective household cooking method to prepare rice with relatively low digestibility and good palatability.

Retaining a large amount of resistant starch in cooked potato through microwave heating after freeze-drying.

Resistant starch (RS) is beneficial for humans, especially for the diabetes. Raw potato had a great deal of RS, while most of which become digestible after gelatinization. Thus, few RS will be retained in potatoes after regular cooking. To preserve RS in cooked potatoes as much as possible, microwave heating before (MFD) and after freeze-drying (FDM) were conducted with three different potatoes. After MFD, the RS content in potatoes was lower than 7% and the RDS content was higher than 45% for three potatoes. However, RS in potatoes treated with FDM was still as high as 40%, similar to that in the raw potatoes. Meantime, FDM caused less browning, produced a certain level of pyrazines, benzeneacetaldehyde and other flavor compounds, endowing cooked potatoes special baked flavor. Freeze-drying before microwave heating is a valuable way to reserve RS in cooked potatoes, which could also be used to reserve high RS content in crisp, chips, and other processed potatoes.

Alarming antibiotics resistance of Helicobacter pylori from children in Southeast China over 6 years.

The increasing rates of antibiotic resistance in Helicobacter pylori (H. pylori) are a major concern of the decreasing eradication rate. Large-scale and long-period studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to describe the temporal changes of antibiotic resistance among children in southeast China. Gastric biopsies obtained from children were cultured for H. pylori from 2015 to 2020. Susceptibility to clarithromycin (CLA), amoxicillin (AML), metronidazole (MTZ), furazolidone (FZD), tetracycline (TET) and levofloxacin (LEV) was tested. Data from 2012 to 2014 reported previously were obtained for comparing the change in temporal trends of antibiotic resistance. A total of 1638 (52.7%) H. pylori strains were isolated from 3111 children recruited. The resistance rates to CLA, MTZ and LEV were 32.8%, 81.7% and 22.8%, respectively. There were 52.9% strains resistant to single resistance, 28.7% to double resistance, and 9.0% to triple resistance. The total resistance rate and resistance rates to CLA, MTZ, LEV, CLA + LEV and CLA + MTZ + LEV increased annually in a linear manner. All resistant patterns except single resistance increased obviously from 2015 to 2017 and 2018 to 2020 compared to that from 2012 to 2014. Double resistance to CLA + MTZ increased significantly with age. The resistance rate to CLA and triple resistance to CLA, MTZ and LEV increased in children with prior H. pylori treatment than that from children without prior treatment. The antibiotic resistance rates of H. pylori were high in a large pediatric population in southeast China from 2015 to 2020. Individual treatment based on susceptibility test is imperative and optimal regimens should be chosen in H. pylori eradication therapy.

A Critical Review on Communication Mechanism within Plant-Endophytic Fungi Interactions to Cope with Biotic and Abiotic Stresses.

Endophytic fungi infect plant tissues by evading the immune response, potentially stimulating stress-tolerant plant growth. The plant selectively allows microbial colonization to carve endophyte structures through phenotypic genes and metabolic signals. Correspondingly, fungi develop various adaptations through symbiotic signal transduction to thrive in mycorrhiza. Over the past decade, the regulatory mechanism of plant-endophyte interaction has been uncovered. Currently, great progress has been made on plant endosphere, especially in endophytic fungi. Here, we systematically summarize the current understanding of endophytic fungi colonization, molecular recognition signal pathways, and immune evasion mechanisms to clarify the transboundary communication that allows endophytic fungi colonization and homeostatic phytobiome. In this work, we focus on immune signaling and recognition mechanisms, summarizing current research progress in plant-endophyte communication that converge to improve our understanding of endophytic fungi.

The Influence of Cesarean Section on the Composition and Development of Gut Microbiota During the First 3 Months of Life.

The intestinal microbiota has emerged as a critical regulator of growth and development in the early postnatal period of life. Cesarean section (CS) delivery is one of the strongest disrupting factors of the normal colonization process and has been reported as a risk factor for disorders in later life. In this study, we dynamically and longitudinally evaluated the impact of CS on the initial colonization pattern and development of gut microbiota by 16 healthy Chinese infants with fecal samples collected at 9 time points (day 5, day 8, day 11, week 2, week 4, week 6, week 7, month 2, and month 3) during the first 3 months of life. The V3-V4 regions of 16S rRNA gene were analyzed by Illumina sequencing. In comparison with vaginally delivered (VD) infants, infants born by CS showed decreased relative abundance of Bacteroides and Parabacteroides and enrichment of Clostridium_sensu_stricto_1, Enterococcus, Klebsiella, Clostridioides, and Veillonella. Most interestingly, Firmicutes/Bacteroidetes ratio was found to be significantly higher in the CS group than in the VD group from day 5 until month 3. Besides, the results of microbial functions showed that the VD group harbored significantly higher levels of functional genes in vitamin B6 metabolism at day 5, day 8, week 2, week 4, week 6, week 7, month 2, and month 3 and taurine and hypotaurine metabolism at day 5, while the phosphotransferase system and starch and sucrose metabolism involved functional genes were plentiful in the CS group at day 11, week 2, week 4, week 6, week 7, and month 2 and at week 2, week 7, and month 2, respectively. Our results establish a new evidence that CS affected the composition and development of gut microbiota in the first 3 months and provide a novel insight into strategies for CS-related disorders in later life.

Assessment of genetic diversity and variety identification based on developed retrotransposon-based insertion polymorphism (RBIP) markers in sweet potato (Ipomoea batatas (L.) Lam.).

Sweet potato, a dicotyledonous and perennial plant, is the third tuber/root crop species behind potato and cassava in terms of production. Long terminal repeat (LTR) retrotransposons are highly abundant in sweet potato, contributing to genetic diversity. Retrotransposon-based insertion polymorphism (RBIP) is a high-throughput marker system to study the genetic diversity of plant species. To date, there have been no transposon marker-based genetic diversity analyses of sweet potato. Here, we reported a structure-based analysis of the sweet potato genome, a total of 21555 LTR retrotransposons, which belonged to the main LTR-retrotransposon subfamilies Ty3-gypsy and Ty1-copia were identified. After searching and selecting using Hidden Markov Models (HMMs), 1616 LTR retrotransposon sequences containing at least two models were screened. A total of 48 RBIP primers were synthesized based on the high copy numbers of conserved LTR sequences. Fifty-six amplicons with an average polymorphism of 91.07% were generated in 105 sweet potato germplasm resources based on RBIP markers. A Unweighted Pair Group Method with Arithmatic Mean (UPGMA) dendrogram, a model-based genetic structure and principal component analysis divided the sweet potato germplasms into 3 groups containing 8, 53, and 44 germplasms. All the three analyses produced significant groupwise consensus. However, almost all the germplasms contained only one primary locus. The analysis of molecular variance (AMOVA) among the groups indicated higher intergroup genetic variation (53%) than intrapopulation genetic variation. In addition, long-term self-retention may cause some germplasm resources to exhibit variable segregation. These results suggest that these sweet potato germplasms are not well evolutionarily diversified, although geographic speciation could have occurred at a limited level. This study highlights the utility of RBIP markers for determining the intraspecies variability of sweet potato and have the potential to be used as core primer pairs for variety identification, genetic diversity assessment and linkage map construction. The results could provide a good theoretical reference and guidance for germplasm research and breeding.