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The barriers of joining in vitro fertilization programs among infertile couples in developing countries:A scoping review
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作者 Andriana K Dewi Anggi L Wicaksana +1 位作者 Muhammad Lutfi Agung Dewanto 《Asian pacific Journal of Reproduction》 2023年第4期147-154,I0001-I0003,共11页
Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors r... Objective:To determine the barriers of joining in-vitro fertilization(IVF)programs among infertile couples in developing countries.Methods:This study assessed infertile couples and the barriers or associated factors resulting in delayed decision-making of joining IVF program by searching databases PubMed,ScienceDirect,EBSCO,ClinicalKey,and Cochrane Library from inception until December 31,2021.Additional search strategies were snowballing literature search and citation tracking.Results:Eleven articles were included in the scoping review.The cost was the greatest barrier of joining IVF program.Limited access and lack of assisted reproductive technology centers,few qualified infertility trained staff,insufficient government support,low priority in government policy,along with sociocultural factors,such as religion and false beliefs or myths were also majorly considered to be associated obstacles.Conclusions:The main barrier associated with IVF program among infertile couples in developing countries is the high cost of the IVF services. 展开更多
关键词 In vitro fertilization Assisted reproductive technology BARRIER Developing countries
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Geographic Distribution of Mating Types in Magnaporthe grisea and the Relationship Between Fertile Isolates in China 被引量:5
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作者 SHEN Ying, Notteghem Jean Loup., Milazzo Joelle., YUAN Xiao-ping, Adreit Henry, ZHAO Xin-hua, WANG Yan-li and Tharreau Didier.(China National Rice Research Institute, Hangzhou 310006, P. R. China National Institute of Agronomic Research ,Unit of Training and Biological Research , Ecology and Plant Pathology, 2 Place Viala , 34062 Montpellier , France International Center for collaboration in Agronomic Research and Development,TA 73 /09 , 34398 Montpellier , Cedex 05 , France) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期648-656,共9页
377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy1... 377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. 73 fertile isolates were tested with SCAR markers of 13 pairs of primers. Preliminary results showed that the geographic distribution of M. grisea existed among isolates collected from the same location as well as different locations and the genetic relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M. grisea was explored in the field as well. 展开更多
关键词 MAGNAPORTHE grisea fertile isolates GEOGRAPHIC Distribution SCARs Genetic relationship
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Fertile island effect in the sedimentary process of Tetraena mongolica Maxim nebkhas in steppe–desert ecotones on the Inner Mongolia Plateau,China
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作者 ZHAI Bo DANG Xiao-hong +1 位作者 LIU Xiang-jie WANG Ji 《Journal of Mountain Science》 SCIE CSCD 2022年第10期2791-2805,共15页
Phytogenic mounds(nebkhas)formed by shrubs are a common phenomenon in arid and semiarid areas.The formation of nebkhas is accompanied by the appearance of the fertile island effect.Quantitative evaluation of the shrub... Phytogenic mounds(nebkhas)formed by shrubs are a common phenomenon in arid and semiarid areas.The formation of nebkhas is accompanied by the appearance of the fertile island effect.Quantitative evaluation of the shrub sand compost island effect is a key link in preventing soil erosion and nutrient loss.This study took the typical shrub Tetraena mongolica in desert areas as the research object and quantified the sand-trapping capacity of the shrub.We revealed the influence of sediment texture and volumetric soil water content on fertile islands during the development of T.mongolica nebkhas.The results showed that(1)the single shrub intercepted large amounts of sediments due to the high density of branches of T.mongolica,forming nebkhas that were positively correlated with the shrub size.(2)The overall soil nutrient content below the shrub was greater than the soil nutrient content outside the shrub,forming a typical fertile island effect.The soil organic carbon(SOC),alkaline hydrolytic nitrogen(AHN),available phosphorus(AP),and available K(AK)content all increased gradually with increasing nebkha volume.Compared with the deep soil of nebkhas,the nutrient content of the surface soil was generally higher.(3)There was a positive correlation between the volumetric water content and nutrient content in nebkhas.(4)The semi-ellipsoid shape of T.mongolica enabled it to intercept large amounts of coarse-grained material.Fine sand(100–250μm)was the main particle size in the sediment aggregates inside the nebkhas.The fine sand content generally increased with increasing shrub size.Redundancy analysis(RDA)revealed that the fine sand content of the nebkha sediments had a strong positive correlation with the soil nutrient content.This paper provides an example for evaluating the fertile island effect during the deposition process of nebkhas in the desert transition zone. 展开更多
关键词 NEBKHAS Sediments Particle-size distribution fertile island Tetraena mongolica Ordos Plateau
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Take Full Advantage of the Fertile Black Soil
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《China Today》 2001年第4期66-67,共2页
关键词 Take Full Advantage of the fertile Black Soil
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The change of the cationic peroxidase in the leaves at the fertile transformation period in Nongken 58s
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作者 HE Zhichang Dept of Plant Sci,College of Life Sci,Wuhan Univ,Wuhan 430072,China 《Chinese Rice Research Newsletter》 1997年第1期11-12,共2页
Nongken 58s is a type of photoperiod sensitivegenic male sterile rice which gives rice to malesterility when illuminated time is longer than13.75 h/d. The photoperiod sensitive stagesare from the differentiation of pr... Nongken 58s is a type of photoperiod sensitivegenic male sterile rice which gives rice to malesterility when illuminated time is longer than13.75 h/d. The photoperiod sensitive stagesare from the differentiation of primary branchprimordum (Ⅱ) in young ears to fullness ofcontents of the pollen (Ⅶ). The changes ofactivity and isoenzymes in cation peroxidase atphotoperiod sensitive stages and the relation- 展开更多
关键词 The change of the cationic peroxidase in the leaves at the fertile transformation period in Nongken 58s
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Untreated Prior Pulmonary Tuberculosis Adversely Affects Pregnancy Outcomes in Infertile Women Undergoing in vitro Fertilization and Embryo Transfer: A Large Retrospective Cohort Study 被引量:6
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作者 GAI Xiao Yan CHI Hong Bin +11 位作者 ZENG Lin CAO Wen Li CHEN Li Xue ZHANG Chen LU Ming NING Lan Ding CHANG Chun ZHANG Wei Xia LIU Ping LI Rong SUN Yong Chang QIAO Jie 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2021年第2期130-138,共9页
Objective Prior pulmonary tuberculosis(PTB) on chest X-ray(CXR) was commonly found in infertile patients receiving examinations before in vitro fertilization and embryo transfer(IVF-ET). It was unclear whether untreat... Objective Prior pulmonary tuberculosis(PTB) on chest X-ray(CXR) was commonly found in infertile patients receiving examinations before in vitro fertilization and embryo transfer(IVF-ET). It was unclear whether untreated PTB would affect pregnancy outcomes after IVF-ET.Method We conducted a retrospective cohort study of 14,254 infertile patients who had received IVFET at Peking University Third Hospital in 2017. Prior PTB was defined as the presence of signs suggestive of old or inactive PTB on CXR, with or without a clinical TB history. Patients who had prior PTB on CXR but had not received a clinical diagnosis and anti-TB therapy were included for analysis. Live birth,clinical pregnancy, and miscarriage rates were compared between the untreated PTB and non-PTB groups.Results The untreated PTB group had significantly lower clinical pregnancy(31.7% vs. 38.1%) and live birth(23.8% vs. 30.6%) rates than the non-PTB group(both P < 0.001). Multivariate analysis revealed that untreated PTB was a risk factor for decreased live birth rate [odds ratio(OR), 0.80;95% confidence interval(CI), 0.66–0.98;P = 0.028] in all patients and for increased miscarriage(OR, 4.19;95% CI,1.69–10.39;P = 0.002) and decreased live birth(OR, 0.45;95% CI, 0.24–0.83;P = 0.011) rates in patients with unexplained infertility.Conclusions Untreated PTB was associated with adverse pregnancy outcomes after IVF-ET, especially in patients with unexplained infertility, highlighting the clinical significance of PTB in this specific patient population. 展开更多
关键词 TUBERCULOSIS Embryo transfer In vitro fertilization INFERTILITY Pregnancy outcome
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A Survey of Correlation Infertility Self-Efficacy with Behavioral Health Scales in Infertile Women 被引量:2
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作者 Mahbobeh Faramarzi Hajar Pasha +3 位作者 Seddigheh Esmailzadeh Farzan Kheirkhah Karimollah Hajian-Tilaki Hajar Salmalian 《Health》 2014年第10期943-949,共7页
Background: Infertility is a unique medical challenge that can have health behavioral consequence on infertile women including lack of self-esteem, depression, anxiety, fertility problem in infertile couples. The aim ... Background: Infertility is a unique medical challenge that can have health behavioral consequence on infertile women including lack of self-esteem, depression, anxiety, fertility problem in infertile couples. The aim of this study was to evaluate correlation between self-efficacy and health behaviors scales in infertile women. Methods: A cross sectional study was conducted on 89 infertile women with mild to moderate depression (Beck scores 10 - 47) who were recruited from Fatemeh Zahra Infertility and Reproductive Health Research Center. All participants completed Self-efficacy Inventory (ISE) and other health behavioral scales (e.g., the Beck Depression Inventory (BDI), Cattle Anxiety Scale (CAS), Fertility Problem Infertility (FPI), and GHQ). Pearson correlation coefficient and Spearman rho correlation coefficient were used to analyze the data. Variables were included in the study if they had a p-value 展开更多
关键词 INFERTILITY SELF-EFFICACY DEPRESSION Stress ANXIETY Health BEHAVIORS FERTILITY Problem
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Investigation into Semen Characteristics of Naturally-Fertile Pairs in Vitro and Their correlation with Fertility in Florida Sandhill Crane
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作者 陈国军 GEORGEF.GEE +1 位作者 JANEM.NICOLICH JOANNAA.TAYLOR 《Journal of Forestry Research》 SCIE CAS CSCD 1998年第2期71-76,共6页
Semen characteristics of naturally fertile pairs and their correlation with fertility of eggs in Florida sandhill crane (Grus canadensis pratensis) were examined. Six pairs were used in this experiment, and all of the... Semen characteristics of naturally fertile pairs and their correlation with fertility of eggs in Florida sandhill crane (Grus canadensis pratensis) were examined. Six pairs were used in this experiment, and all of them that had bred before were housed in open individual pens. These pairs were isolated physically each other but not visually and audibly. Semen was collected twice (Tuesday morning and Friday afternoon) from February 26 to June 4, 1993. The standard methods at Patuxent Wildlife Research Center were used collecting and evaluating the semen and spermatozoa. and incubating the eggs. There were statistically individual variations (p<0.05) about successful collecting attempts, semen volume, semen concentration, spermatozoon’s motility,spermatozoon’s number per collection, live spermatozoon’s number, male’s response to semen collection, and morphology of spermatozoa except the giant cell. There was a significantly (p<0.05, correlation coefficient was (0.73 or (1 .00) negative correlation between fertility of eggs and the multiple value of semen (sperm) characteristics of naturally fertile pairs in Florida sandhill crane. 展开更多
关键词 Florida sandhill CRANE GRUS CANADENSIS pratensis SEMEN (sperm) characteristic Egg FERTILITY
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Old climatically-buffered infertile landscapes(OCBILs):more than harsh habitats,Atlantic Forest inselbergs can be drivers of evolutionary diversity
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作者 Felipe de CARVALHO ARAÚJO Natália de AGUIAR-CAMPOS +2 位作者 Cleber Rodrigo de SOUZA Eduardo de Paiva PAULA Rubens Manoel dos SANTOS 《Journal of Mountain Science》 SCIE CSCD 2022年第9期2528-2543,共16页
Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation ... Granite-gneiss rock outcrop inselbergs are ancient stable ecosystems with old,climaticallybuffered infertile landscapes(OCBILs).Although inselbergs provide key ecosystem services,little is done for their conservation and,so far,a lot of their unknown evolutionary history has already been lost by human activities.Using a fine-scale approach,here we tested if habitat and environmental filtering(the inselberg’s harshness)affect the evolutionary diversity of an Atlantic Forest inselberg in Brazil.We recorded all trees with a diameter at breast height≥5cm in 20 plots in four habitat types(total sampled area of 0.8 hectares),from highest to lowest:island,hillside,foothill,and semideciduous forest(matrix).We also collected soil samples for chemical,textural and physical soil characterization.We fitted linear models to test the effects of soil and habitat on plotlevel metrics of phylogenetic diversity and structure,lineage diversity,phylogeneticβ-diversity,and evolutionary distinctiveness.We found that the upper inselberg habitats contain a distinct set of ancient,closely related,harsh-tolerant lineages,as well as a subset of lineages that persist under harsh conditions with a certain degree of water availability.The inferior inselberg habitats harbor higher lineage diversity than expected by chance.Soil strongly predicted evolutionary diversity.We concluded that soil depth,slope,nutrients and texture(environmental filtering)and habitat types and topography(habitat filtering)shape the evolutionary history contained in fine-scale inselberg habitats,which should encourage the conservation of these ancient ecosystems. 展开更多
关键词 Phylogenetic diversity Atlantic Forest Niche conservatism Environmental filters Soil fertility Terrestrial Island
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Can Greater Flamingo Recognize Fertile <i>vs.</i>Infertile Egg? A Single Case Study
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作者 Camillo Sandri Barbara Regaiolli +2 位作者 Matilde Franchin Alessandra Piccirillo Caterina Spiezio 《Open Journal of Animal Sciences》 2017年第2期232-239,共8页
Fertility of captive flamingos varies between flocks, species and seasons. Individuating infertile eggs could be helpful to facilitate important decisions. Wild animals could be encouraged to abandon the nest or not, ... Fertility of captive flamingos varies between flocks, species and seasons. Individuating infertile eggs could be helpful to facilitate important decisions. Wild animals could be encouraged to abandon the nest or not, whereas in captivity removing non-viable egg would lead birds to lay a new one. The aim of this study was to investigate the parental behaviour of a pair of greater flamingos (Phoenicopterus roseus) in the presence of a fertile and an infertile egg. Data on the posture and behaviours of the pair on the nest were collected over two different periods: first period—an infertile egg was laid;second period—a fertile egg was laid. For each period, 28 ten-minute sessions per flamingo partner were run. Results revealed that female flamingo spent significantly more time standing on the nest in the first than in the second period (P = 0.010). Moreover, when standing on the nest, the female performed significantly more egg-care behaviour (attention to the egg, egg rotation/moving) in the first than in the second period (P = 0.010). No significant differences between periods emerged in the male flamingo posture on the nest and behaviours. Findings from this study suggest that female flamingos stand on the nest longer if the egg is infertile, paying more attention and examining it deeply. This study provides new insights into greater flamingo parent-embryo communication. Future research is needed to improve our knowledge on this topic, as well as on the husbandry of this species in the controlled environment. 展开更多
关键词 Phoenicopterus roseus EGG Fertility EGG Care PARENTAL Behaviour
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Medical versus surgical treatment for early pregnancy loss in infertile patients: Which approach facilitates more rapid return to subsequent treatment cycle?
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作者 Victoria Vallejo Hilde I. G. Cotton +3 位作者 Joseph A. Lee Enrique Cervantes Benjamin Sandler Alan B. Copperman 《Open Journal of Obstetrics and Gynecology》 2012年第4期356-360,共5页
Patients and physicians confront a challenging dynamic when an early pregnancy loss (EPL) occurs after fertility treatment (FT). Our study focused on the time to resumption of FT in patients managed medically (Cytotec... Patients and physicians confront a challenging dynamic when an early pregnancy loss (EPL) occurs after fertility treatment (FT). Our study focused on the time to resumption of FT in patients managed medically (Cytotec) compared to in those managed surgically with dilatation and curettage (D&C). A retrospective analysis from 2003-2010 of patients receiving treatment for an EPL. Misoprostol (Cytotec) patients were compared with a randomly selected control group (D&C). Both the time from the date of treatment to the date at which βhCG reached x2. No statistical significance was observed for resumption of FT between groups. Cytotec group had a greater maintenance of retained products of conception versus D&C population (26% vs 2%;p = 0.01). More D&C patients received karyotype results (68% vs 5%). A significant difference was not found in resumption time to the next fertility treatment between the medically and surgical treatment. More medically managed patients RPOC requiring D&C. Although a D&C is more likely to provide karyotype results, medical management is a viable alternative. 展开更多
关键词 MISOPROSTOL DILATATION and Curetta FERTILITY Treatment Cytotec RETAINED Products of CONCEPTION
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Effect of Fasting of Ramadan on Infertile Women Undergoing In-Vitro Fertilization/Intracytoplasmic Sperm Injection Cycles: A Prospective Cohort Study
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作者 Karim A. Wahba 《Open Journal of Obstetrics and Gynecology》 2016年第3期171-179,共9页
Objective: To determine the effects of fasting of Ramadan in patients undergoing in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Design: A prospective cohort study conducted during Ramadan... Objective: To determine the effects of fasting of Ramadan in patients undergoing in-vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) cycles. Design: A prospective cohort study conducted during Ramadan. Setting: Ain Shams University IVF centre. Population: Three hundred fasting, infertile women undergoing their first trial of IVF/ICSI and 300 non-fasting matched controls undergoing the same procedure during Ramadan. Methods: Anxiety and depression were measured by the Hospital Anxiety and Depression Scale, at the start of the induction protocol. All the successful pregnant women were followed up until delivery. Main Outcome Measures: The primary outcome measure was the live birth rate. Results: The live birth rate was higher in the fasting group than in the non-fasting group;this was not significant (43% vs. 40%, P = 0.46). The fasting group needed higher doses and durations of induction. Embryo quality did not differ between both groups. The pregnancy complication rate among successful cases was higher in the fasting group (52.9% vs. 40.4%, P = 0.03);however, the frequencies of anxiety and depression were significantly lower than those in the non-fasting group (18% vs. 38%, P P < 0.00001, respectively). Conclusion: Fasting during Ramadan does not seem to significantly affect the IVF/ICSI outcome;however, it significantly decreased the anxiety and depression usually associated with these procedures. 展开更多
关键词 FASTING RAMADAN INFERTILITY In-Vitro Fertilization Intracytoplasmic Sperm Injection
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Altered microRNA expression profiles of human spermatozoa in normal fertile men of different ages
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作者 Ming-Jia Zhao Yao-Nan Zhang +7 位作者 Yong-Ping Zhao Xian-Bing Chen Bao-Sheng Han Ning Ding Yi-Qun Gu Shu-Song Wang Jing Ma Mei-Ling Liu 《Asian Journal of Andrology》 SCIE CAS CSCD 2023年第6期737-744,共8页
MicroRNAs(miRNAs)are mediators of the aging process.The purpose of this work was to analyze the miRNA expression profiles of spermatozoa from men of different ages with normal fertility.Twenty-seven donors were divide... MicroRNAs(miRNAs)are mediators of the aging process.The purpose of this work was to analyze the miRNA expression profiles of spermatozoa from men of different ages with normal fertility.Twenty-seven donors were divided into three groups by age(Group A,n=8,age:20–30 years;Group B,n=10,age:31–40 years;and Group C,n=9,age:41–55 years)for high-throughput sequencing analysis.Samples from 65 individuals(22,22,and 21 in Groups A,B,and C,respectively)were used for validation by quantitative real-time polymerase chain reaction(qRT-PCR).A total of 2160 miRNAs were detected:1223 were known,937 were newly discovered and unnamed,of which 191 were expressed in all donors.A total of 7,5,and 17 differentially expressed microRNAs(DEMs)were found in Group A vs B,Group B vs C,and Group A vs C comparisons,respectively.Twenty-two miRNAs were statistically correlated with age.Twelve miRNAs were identified as age-associated miRNAs,including hsa-miR-127-3p,mmu-miR-5100_L+2R-1,efu-miR-9226_L-2_1ss22GA,cgr-miR-1260_L+1,hsa-miR-652-3p_R+1,pal-miR-9993a-3p_L+2R-1,hsa-miR-7977_1ss6AG,hsa-miR-106b-3p_R-1,hsa-miR-186-5p,PC-3p-59611_111,hsa-miR-93-3p_R+1,and aeca-mir-8986ap5_1ss1GA.There were 9165 target genes of age-associated miRNAs.Gene Ontology(GO)analysis of the target genes identified revealed enrichment of protein binding,membrane,cell cycle,and so on.The Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis of age-related miRNAs for target genes revealed 139 enriched pathways,such as signaling pathways regulating stem cell pluripotency,metabolic pathways,and the Hippo signaling pathway.This suggests that miRNAs play a key role in male fertility changes with increasing age and provides new evidence for the study of the mechanism of age-related male fertility decline. 展开更多
关键词 age FERTILITY MICRORNA SPERMATOZOA
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minimal genome design to maximally guarantee fertile inter-subspecific hybrid rice
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作者 Penghui Zhou Zhengji Wang +17 位作者 Xingchen Zhu Yao Tang Liang Ye Huihui Yu Yating Li Ningke Zhang Ting Liu Tian Wang Yuying Wu Dengyun Cao Yuan Chen Xu Li Qinglu Zhang Jinghua Xiao Sibin Yu Qifa Zhang Jiaming Mi Yidan Ouyang 《Molecular Plant》 SCIE CSCD 2023年第4期726-738,共13页
Hybrid rice has made considerable contributions to achieve the ambitious goal of food security for the world's population.Hybrid rice from indica/xian and japonica/geng subspecies shows much higher heter-osis and ... Hybrid rice has made considerable contributions to achieve the ambitious goal of food security for the world's population.Hybrid rice from indica/xian and japonica/geng subspecies shows much higher heter-osis and is thereby an important innovation in promoting rice production in the next decade.However,such inter-subspecific hybrid rice has long suffered from serious hybrid sterility,which is a major challenge that needs to be addressed.In this study,we performed a genome design strategy to produce fertile inter-subspecific hybrid by creation of wide compatibility varieties that are able to overcome hybrid sterility.Based on combined genetic analyses in two indica-japonica crosses,we determined that four hybrid ste-rility loci,S5,f5,pf12 and Sc,are the major QTLs controlling inter-subspecific hybrid sterility and thus the minimal targets that can be manipulated for breeding sub-specific hybrid rice.We then cloned the pf12 lo-cus,one of the most effective loci for hybrid male sterility,by map-based cloning,and showed that artificial disruption of pf12A gene at this locus could successfully rescue hybrid fertility.We further dissected the genetic basis of wide compatibility using three pairwise crosses from a wide-compatibility variety Dular and representative indica and japonica varieties.On this basis,we constructed and assembled different combinations of naturally compatible alleles of four loci,S5,Sc,pf12,and f5,and found that the improved lines could fully recover pollen and embryo sac fertility in test-crossed F,s,thereby completely fulfilling the demands of inter-subspecific hybrid spikelet fertility in agricultural production.This breeding scheme would facilitate redesign of future inter-subspecific hybrid rice with a higher yield potential. 展开更多
关键词 BREEDING FERTILITY thereby
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A dynamic regulation of nitrogen on floret primordia development in wheat
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作者 Zhen Zhang Yujing Li +6 位作者 Yuxun Wu Xiaoyu Zheng Xiaolei Guo Wan Sun Zhencai Sun Zhimin Wang Yinghua Zhang 《The Crop Journal》 SCIE CSCD 2024年第1期271-280,共10页
Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilizati... Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive florets.Because the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under N2.There were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 treatments.Correspondingly,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to N0.Clearly,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing NFFs.There was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained unused.Therefore,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs. 展开更多
关键词 fertile florets Floret primordia Grain number Meiotic ability Morphological development
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen Lili Zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong Zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China 被引量:1
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作者 Zongyi Wu Xiaolong Feng +1 位作者 Yumei Zhang Shenggen Fan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期430-443,共14页
China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the ... China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies. 展开更多
关键词 food security fertilizer manufacturing subsidies agri-food systems greenhouse gas emissions
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Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil
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作者 Minghui Cao Yan Duan +6 位作者 Minghao Li Caiguo Tang Wenjie Kan Jiangye Li Huilan Zhang Wenling Zhong Lifang Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期698-710,共13页
Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidif... Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity reduction.Meanwhile,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity benefits.However,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain uncertain.To bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure application.All fertilization treatments were designed to have equal N input.Our results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with CF.SOC,AP,and the soil C:N ratio were mainly responsible for microbial community variations.The co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,respectively.These specific taxa are implicated in soil macroelement turnover.Random Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop yield.The present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies. 展开更多
关键词 FERTILIZATION manure substitution soil fertility maize yield bacterial community
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Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation
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作者 Lichao Zhai Lihua Zhang +7 位作者 Yongzeng Cui Lifang Zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong Wu Xiuling Jia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1179-1194,共16页
Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CA... Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high yields.In order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical fertilizer.Compared with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior kernels.These effects were largely due to the improved filling and starch accumulation of inferior kernels.However,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most cases.Leaf area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or OFCF2.Compared with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and DMA.Moreover,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N uptake.Analyses showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position effect.In conclusion,the combined application of 15-30%organic fertilizer and 70-85%chemical fertilizer alleviated the kernel position effect in summer maize by improving post-silking N uptake and DMA.These results provide new insights into how CAOFCF can be used to improve maize productivity. 展开更多
关键词 chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer
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Production traits and fertility of reciprocal hybrids between Argopecten irradians irradians and A.i.concentricus
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作者 Jinjing WANG Junhao NING +6 位作者 Xia LU Min CHEN Guilong LIU Xin XU Quanchao WANG He XU Chunde WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期304-315,共12页
The two bay scallop subspecies,Argopecten irradians irradians(NN)and A.i.concentricus(SS),are fast growing and major cultured bivalves in China.However,their relatively small sizes and decreasing production traits cau... The two bay scallop subspecies,Argopecten irradians irradians(NN)and A.i.concentricus(SS),are fast growing and major cultured bivalves in China.However,their relatively small sizes and decreasing production traits caused by long-term inbreeding have been major concerns to the industry in the last two decades.Hybridization between the two bay scallop subspecies may provide a new approach to breed a new variety with superior production traits for the industry.For this end,in this study,we hybridized the two bay scallop subspecies in order to obtain a new strain that incorporates the genes of both subspecies.No significant difference was found in fertilization rate,hatching rate and metamorphosis rate between the purebred and crossbred cohorts(NN♀×SS♂,denoted as NS;SS♀×NN♂,denoted as SN).Both mating strategy(intra-vs.inter-population crosses)and egg origin had significant effects on growth and survival at the larval stage.Heterosis was observed in the crossbred and was more pronounced in older stages.Genetic diversity of the reciprocal hybrids,especially that of SN,was increased compared with the purebred cohorts.Almost all hybrids were completely fertile and able to reproduce by selffertilization or by backcrossing with either parent.Apparently,male sterile individuals whose gonads were fully occupied by the ovary part at mature stage were found in the hybrids for the first time.The hybrids,especially SN,may provide precious germplasm resources for the production of ternary hybrids with the Peruvian scallop,A.purpuratus. 展开更多
关键词 bay scallop HYBRIDIZATION growth survival HETEROSIS FERTILITY ternary hybrids
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