Mohammad Erfatpour, Kristin J Simons, Jayanta Roy, Jose C Figueroa-Cerna, Rian Lee, James Beaver, Phillip E McClean, Juan M Osorno
{"title":"Fine mapping and identification of causal alleles at the Ur-11 locus controlling rust resistance in common bean (Phaseolus vulgaris L.).","authors":"Mohammad Erfatpour, Kristin J Simons, Jayanta Roy, Jose C Figueroa-Cerna, Rian Lee, James Beaver, Phillip E McClean, Juan M Osorno","doi":"10.1007/s00122-025-04836-9","DOIUrl":"10.1007/s00122-025-04836-9","url":null,"abstract":"<p><p>The Middle American rust resistance gene Ur-11 present in common bean (Phaseolus vulgaris L.) confers resistance to all but one known race of the pathogen Uromyces appendiculatus (Pers.) Unger. Even though progress has been made in understanding the host-pathogen interactions between common bean and U. appendiculatus, the causal alleles of the majority of rust resistance loci, including Ur-11, remain unknown. A genome-wide association study (GWAS) was conducted to identify genomic regions associated with resistance to the U. appendiculatus race 31-22, which is avirulent to Ur-11 but virulent to other Middle American rust resistance genes. GWAS using genotypic data consisting of approximately 70,959 SNP markers and phenotypic data based on the median reaction type (1-9 scale) of a panel of 357 Middle American breeding lines and cultivars, plus 5 germplasm lines with the Ur-11 locus derived from PI 181996, located Ur-11 on chromosome Pv11. Twenty-seven SNP markers clustered in the 55.16-55.56 Mb region of the P. vulgaris UI111 reference. Multiple DNA sequence alignments detected a missense mutation [c.1,328A > G] in the PvUI111.11G202400 gene model that encodes a leucine-rich repeat-containing protein in response to race 31-22. A PCR allele competitive extension marker (PACE) was developed and tested across a panel of ~ 700 Middle American dry bean genotypes. No recombination event was observed for the PACE marker among the tested genotypes; suggesting that the polymorphism on which it is based is very close to or in the Ur-11 gene. This PACE marker will be a useful and reliable marker for marker-assisted selection of Ur-11-based resistance to bean rust.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 3","pages":"55"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850475/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Knocking out artificially selected gene GmAOC4<sup>H8</sup> improves germination in soybean.","authors":"Wei Zhang, Songsong Li, Wenjing Xu, Qiong Wang, Hongmei Zhang, Xiaoqing Liu, Xin Chen, Donghe Xu, Huatao Chen","doi":"10.1007/s00122-025-04840-z","DOIUrl":"10.1007/s00122-025-04840-z","url":null,"abstract":"<p><p>Seed germination is an essential stage in the life cycle of flowering plants, influencing the field emergence rates of seeds. Consequently, the role of GmAOC4 in soybean seed germination was investigated in the present study. Results suggested that the chloroplast-localized GmAOC4 exhibited high expression levels in the roots and young pods and during the seed germination stage in soybeans. It was found that GmAOC4 has been artificially selected during soybean domestication and improvement and that GmAOC4<sup>H8</sup> showed repressed seed germination, of which the frequency in landraces and cultivars decreased when compared with wild soybean. Knocking out GmAOC4<sup>H8</sup> via CRISPR/Cas9 led to enhanced germination in gmaoc4 mutants, suggesting its negative regulation on seed germination in soybeans. Additionally, decreased endogenous jasmonic acid (JA) and JA precursor, 12-oxo-phytodienoic acid, were found in gmaoc4 mutants. RNA-seq analyses revealed that 91 and 269 differentially expressed genes (DEGs) were up-regulated and down-regulated in gmaoc4 mutants, respectively. Among these DEGs, three genes were involved in JA biosynthetic and signaling pathways. Our results offer new insights into the mechanism of soybean seed germination regulation by GmAOC4.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 3","pages":"54"},"PeriodicalIF":4.4,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143484026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploring resistance mechanisms and identifying QTLs for brown planthopper in tropical and subtropical rice (Oryza sativa L.) germplasm.","authors":"Fugang Huang, Zongqiong Zhang, Shuolei Liao, Juan Shen, Lanzhi Long, Jingying Li, Xiaohui Zhong, Zuyu Liao, Baiyi Lu, Fahuo Li, Zhe Jiang, Ling Cheng, Caixian Wang, Xiuzhong Xia, Xinghai Yang, Hui Guo, Baoxuan Nong, Danting Li, Yongfu Qiu","doi":"10.1007/s00122-025-04839-6","DOIUrl":"10.1007/s00122-025-04839-6","url":null,"abstract":"<p><strong>Key message: </strong>A total of 4006 tropical and subtropical rice germplasms were screened for brown planthopper resistance, and the resistance mechanisms of 63 highly resistant accessions were characterized. This led to the designation of three novel resistance QTLs: Bph47, Bph48, and Bph49. The brown planthopper (BPH) is a significant piercing-sucking pest of rice plants that causes widespread destruction globally. Discovering new germplasms and genes for BPH resistance is essential for enhancing genetic diversity in rice breeding. In this study, 4006 rice accessions from tropical and subtropical regions were screened for BPH resistance at the seedling stage, and 63 accessions with high-resistant were identified. Of these, 59 accessions exhibited high resistance to BPH at the adult stage. The 63 accessions displayed widespread variation in key agronomic traits, though most were generally unsatisfactory. Assessments of antixenosis, antibiosis, and tolerance indicated diverse resistance mechanisms in the 63 accessions, with the majority (39/63) demonstrating both antixenosis and antibiosis. Microscopic observations and physiological assessments revealed significant differences in vascular bundle structure, fiber content, and activity of defense-related enzymes between the 63 high-resistance and 27 susceptible ones. Furthermore, correlation analysis highlighted a substantial positive relationship between BPH resistance and parameters such as rice trypsin inhibitor (RTI) levels and width of the sclerenchyma layer (WSL). Genetic analysis of F<sub>2:3</sub> segregating populations from four resistant accessions crossed with the susceptible rice variety 9311 identified three novel major-effect quantitative-trait loci (QTLs) located on chromosome 1L (690 kb and 1.84 Mb) and 5S (295 kb). This study significantly enriched the BPH-resistant germplasm sources and genes, highlighting the varied resistance mechanisms of rice against BPH.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 3","pages":"49"},"PeriodicalIF":4.4,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143459577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giulia Frascarelli, Teresa R Galise, Nunzio D'Agostino, Donata Cafasso, Salvatore Cozzolino, Gaia Cortinovis, Francesca Sparvoli, Elisa Bellucci, Valerio Di Vittori, Laura Nanni, Alice Pieri, Marzia Rossato, Leonardo Vincenzi, Andrea Benazzo, Massimo Delledonne, Elena Bitocchi, Roberto Papa
{"title":"The evolutionary history of the common bean (Phaseolus vulgaris) revealed by chloroplast and nuclear genomes analysis.","authors":"Giulia Frascarelli, Teresa R Galise, Nunzio D'Agostino, Donata Cafasso, Salvatore Cozzolino, Gaia Cortinovis, Francesca Sparvoli, Elisa Bellucci, Valerio Di Vittori, Laura Nanni, Alice Pieri, Marzia Rossato, Leonardo Vincenzi, Andrea Benazzo, Massimo Delledonne, Elena Bitocchi, Roberto Papa","doi":"10.1007/s00122-025-04832-z","DOIUrl":"10.1007/s00122-025-04832-z","url":null,"abstract":"<p><strong>Key message: </strong>The origin of common bean was investigated throughout chloroplast and nuclear WGS data considering recombination events. Our results support the Mesoamerican origin of common bean. The remarkable evolutionary history of the common bean (Phaseolus vulgaris L.) has led to the emergence of three wild main gene pools corresponding to three different eco-geographical areas: Mesoamerica, the Andes and northern Peru/Ecuador. Recent works proposed novel scenarios, and the northern Peru/Ecuador population has been described as a new species called P. debouckii, rekindling the debate about the origin of P. vulgaris. Here we shed light on the origin of P. vulgaris by analyzing the chloroplast and nuclear genomes of a large varietal collection representing the entire geographical distribution of wild forms including a large collection of Mesoamerican and Andean individuals. We assembled 37 chloroplast genomes de novo and used them to construct a time frame for the divergence of the genotypes under investigation, revealing that the separation of the Mesoamerican and northern Peru/Ecuador gene pools occurred ~ 0.15 Mya. Our results clearly support a Mesoamerican origin of the common bean and reject the recent P. deboukii hypothesis. These results also imply two independent migratory events from Mesoamerica to the North and South Andes, probably facilitated by birds. Our work represents a paradigmatic example of the importance of taking into account the genetic rearrangements produced by recombination when investigating phylogeny and of the analysis of wild forms when studying the evolutionary history of a crop species.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"47"},"PeriodicalIF":4.4,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11805837/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143371155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Histone acetyltransferase Sas3 in Phomopsis liquidambaris promotes spermidine biosynthesis against Fusarium graminearum in wheat.","authors":"Xinru Cui, Zhi Yang, Longshen Wang, Yuxin Dong, Sitong Ke, Zhichun Zhan, Chuanchao Dai, Yanzhen Mei","doi":"10.1007/s00122-025-04833-y","DOIUrl":"10.1007/s00122-025-04833-y","url":null,"abstract":"<p><strong>Key message: </strong>Spermidine production in the endophytic fungus Phomopsis liquidambaris is regulated by Sas3, and spermidine promotes resistance to Fusarium graminearum by increasing the expression of immune-related indicators in wheat. Fusarium head blight (FHB) is a common wheat disease caused mainly by Fusarium graminearum. The present study showed that overexpression of the histone acetyltransferase Sas3 in Phomopsis liquidambaris regulated the synthesis of spermidine and promoted resistance to F. graminearum in wheat. Sas3 localized in the nucleus plays a key role in acetylating lysines 9 and 14 of histone H3 (H3K9 and H3K14) and clearly promotes the development and growth of P. liquidambaris in the overexpression strain OE-Sas3 and knockout strain Ko-Sas3. The OE-Sas3 strain promoted the growth of wheat seedlings and increased the level of reactive oxygen species (ROS) pumps, which increased the activities of the catalase (CAT) and peroxidase (POD) and the expression levels of genes involved in the jasmonic acid, ethylene, and salicylic acid pathways. Furthermore, OE-Sas3 increased the level of resistance of wheat to F. graminearum through the positive regulation of spermidine biosynthesis, which reduced the incidence of wheat spike disease from 76 to 54% and that of grain disease from 52.35 to 32.68%. This study provides a new perspective for the application of P. liquidambaris as a biocontrol agent via rational design and improved FHB resistance.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"48"},"PeriodicalIF":4.4,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143374286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiuyu Zhang, Bing Han, Di Cui, Zhengwu Zhao, Longzhi Han, Xiaoding Ma
{"title":"Genome-wide association study to identify candidate genes for submergence tolerance during rice seed germination.","authors":"Qiuyu Zhang, Bing Han, Di Cui, Zhengwu Zhao, Longzhi Han, Xiaoding Ma","doi":"10.1007/s00122-025-04830-1","DOIUrl":"10.1007/s00122-025-04830-1","url":null,"abstract":"<p><strong>Key message: </strong>Submergence tolerance QTLs for rice germination were identified via a genome-wide association study, and a new causal gene, LOC_Os06g17260, was identified. Submergence stress is a major obstacle limiting the application of direct seeding in rice cultivation. Rapid bud and root growth helps plants establish a stronger growth base and improve their submergence tolerance. Therefore, mining genes for bud length (BL) and root length (RL) helps in the development of varieties that are adaptable to submergence and improve seedling emergence and yield of direct-seeded rice. In this study, a genome-wide association study of BL and RL was performed on a diverse rice collection consisting of 300 accessions. We identified a total of 37 QTLs, 13 of which had phenotypic contributions > 10%. The novel QTLs qBL6.2/qRL6.8, qBL6.3/qRL6.9, qBL6.4/qRL6.10, and qBL6.5/qRL6.11 on chromosome 6 were stably detected across BL and RL, and a total of 31 genes were detected in these four intervals. Concerning the gene annotation information and expression profiles, LOC_Os06g17090, LOC_Os06g17120, LOC_Os06g17140, LOC_Os06g17220, and LOC_Os06g17260 were selected as possible target genes. Through the validation of a knockout transgenic experiment, LOC_Os06g17260 was identified as the causal gene for submergence tolerance in rice at the germination stage. LOC_Os06g17260 encodes UDP-glucoronosyl and a UDP-glucosyl transferase domain-containing protein and contains two major haplotypes, with the Hap1 germplasm presenting greater submergence tolerance at the germination stage. These results provide new clues for exploring the molecular mechanisms that regulate submergence tolerance in rice and provide a promising source of genes for the molecular breeding of direct-seeded rice.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"45"},"PeriodicalIF":4.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143190712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Mapping and validation of QTkw.cau-3DL, a major QTL controlling thousand-kernel weight in wheat.","authors":"Xi He, Jilu Liu, Xiaomeng Ren, Shurong Wei, Zhenzhen Zhu, Fuping Zhang, Sijia Hu, Yanpeng Ding, Fangyao Sun, Dong Han, Guihua Bai, Zhongfu Ni, Qixin Sun, Zhenqi Su","doi":"10.1007/s00122-025-04824-z","DOIUrl":"10.1007/s00122-025-04824-z","url":null,"abstract":"<p><strong>Key message: </strong>A novel major QTL, QTkw.cau-3DL, for thousand-kernel weight has been identified on the wheat chromosome arm 3DL and enhances grain yield by 6.2% under field conditions. Increasing kernel weight is an effective way to improve yield potential in wheat. The identification of major quantitative trait loci (QTL) for kernel weight, without negative effects on other yield-related traits, is crucial for continuous yield improvement. We developed a population of F<sub>6</sub> recombinant inbred lines from Jimai 120 × Jimai 325 and identified eight QTL for thousand-kernel weight, kernel length, and kernel width across five environments. The population was genotyped using Wheat15K SNP arrays and QTL analysis found that one QTL, QTkw.cau-3DL, on the chromosome arm 3DL consistently showed major effects on TKW and KL in five field experiments. This QTL accounted for up to 16.43% and 13.87% of phenotypic variation, respectively. QTkw.cau-3DL was confined to a 5.72-Mb (3.48 cM) interval between 554.39 Mb and 560.11 Mb. This QTL was validated in a pair of NILs and in a new population. QTkw.cau-3DL increased kernel weight per spike without any negative effect on heading data, plant height, spike length, spikelet number per spike, or kernels number per spike. It increased grain yield by 6.2% under regular field production conditions. Haplotype analysis and geographical distribution in a nationwide collection of 630 wheat cultivars showed that QTkw.cau-3DL has not been widely deployed in Chinese wheat breeding programs. QTkw.cau-3DL is a novel QTL for increasing TKW through increasing KL; therefore, it is an important locus for enhancing wheat grain yield. The tightly linked, user-friendly markers developed in this study should facilitate map-based cloning and marker-assisted selection of the QTL in wheat breeding programs.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"46"},"PeriodicalIF":4.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143190713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Pepper (Capsicum annuum L.) AP2/ERF transcription factor, CaERF2 enhances salt stress tolerance through ROS scavenging.","authors":"Jin Zhao, Miao Huang, Jing Liu, Junyi Cai, Yihan He, Wenjie Zhao, Chaozhong Liu, Yongjun Wu","doi":"10.1007/s00122-025-04823-0","DOIUrl":"10.1007/s00122-025-04823-0","url":null,"abstract":"<p><strong>Key message: </strong>The AP2/ERF transcription factor CaERF2 in pepper enhanced salt tolerance by scavenging reactive oxygen species. The effects of salt stress on plant development and progression are substantial. Ethylene response factor transcription factors (TFs) play a crucial role in responses to salt stress. Their functions in the salt response, particularly in pepper, are still mostly unknown. This study revealed the function of CaERF2 in salt tolerance of pepper plants. CaERF2 expression was dramatically increased in pepper plants following salt stress treatment. Under salinity treatment, CaERF2-silenced pepper showed decreased activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), as well as reduced transcription levels of reactive oxygen species (ROS) scavenging-related genes, resulting in increased O<sup>2-</sup> and H<sub>2</sub>O<sub>2</sub> accumulation and enhanced salt sensitivity. In contrast, overexpression of CaERF2 (OE) in Nicotiana benthamiana resulted in improved salt tolerance. Under salt stress, the OE lines outperformed the wild type in terms of seed germination rates, root lengths, the activity of SOD, POD, and CAT, and ROS-scavenging-related gene transcription. This study demonstrates that CaERF2 effectively enhances the salt tolerance in pepper by adjusting ROS homeostasis. This finding offers fresh perspectives on the significance of plant ERF2 and key candidate genes in the molecular breeding of salt-tolerant crops.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"44"},"PeriodicalIF":4.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143081090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dongho Lee, Tri D Vuong, James G Shannon, Qijian Song, Feng Lin, Henry T Nguyen
{"title":"QTL mapping and whole-genome sequencing analysis for novel genetic resources associated with sucrose content in soybean [Glycine max (L.) Merr.].","authors":"Dongho Lee, Tri D Vuong, James G Shannon, Qijian Song, Feng Lin, Henry T Nguyen","doi":"10.1007/s00122-024-04808-5","DOIUrl":"10.1007/s00122-024-04808-5","url":null,"abstract":"<p><strong>Key message: </strong>A major QTL for sucrose content was mapped on chromosome 8 in PI 506593. The novel genetic variants and candidate genes were further identified within the major QTL. Sucrose in soybean [Glycine max (L.) Merr.] contribute to animal feed efficiency and natural sweetness of soy products. Thus, identifying novel genetic resources, such as quantitative trait loci (QTL), associated with sucrose content in soybean is essential for enhancing seed values. In this study, two recombinant inbred line populations derived from the same high sucrose donor parent, PI 506593, were used to identify significant QTLs. A total of 11 sucrose-related regions on chromosomes (Chrs.) 4, 5, 6, 8, 10, and 13 were identified using QTL analysis. Among them, four QTLs (qSUC_08.1, qSUC_08.2, qSUC_08.3, and qSUC_08.4) were clustered in the interval of 40,597,410-42,861,364 bp on Chr. 8, which was considered major QTL region. A desirable marker at 41,834,095 bp was tested in two populations, showing that two phenotypically extreme groups were efficiently differentiated. We further identified 44 and 54 candidate genes with non-synonymous mutations in the major QTL region based on the annotations of Wm82.a2.v1 and Wm82.a5.v1 assemblies, respectively. Among 54 candidate genes from Wm82.a5.v1, Protein Variation Effect Analyzer (PROVEAN) revealed that 18 genes contained 34 variants that had deleterious impacts on biological functions. RNA-seq analysis highlighted five candidate genes that were highly expressed in pod and seed tissues during reproductive stages and other plant parts. A gene, Gm_Wm82_23219 (Glyma.08G293800, Wm82.a2.v1) encoding proline-rich protein 4-like, was highlighted in both PROVEAN and RNA-seq analyses. Novel findings in this study will be valuable genetic resources in soybean breeding programs that aim to improve efficiency in animal feed and human food.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"43"},"PeriodicalIF":4.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11788231/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143081092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improving a hybrid from within itself.","authors":"Rex Bernardo","doi":"10.1007/s00122-025-04831-0","DOIUrl":"10.1007/s00122-025-04831-0","url":null,"abstract":"<p><strong>Key message: </strong>Improving a hybrid by transferring partially dominant alleles from one parent to the other is feasible if the median level of dominance is moderate and prediction accuracy is high. Convergent improvement within a P<sub>1</sub> × P<sub>2</sub> single-cross hybrid attempts to transfer partially dominant favorable alleles from P<sub>1</sub> to P<sub>2</sub> and from P<sub>2</sub> to P<sub>1</sub>. My objective in this simulation study was to determine if convergent improvement is a feasible procedure to develop a better single cross. Heterozygote effects (d) and homozygote effects (a) at quantitative trait loci (QTL) were resampled from an empirical distribution of genomewide marker estimates of d and a for maize (Zea mays L.) grain yield. The d values were scaled (d scale = 30%, 45%, and 60%) to account for the known upward bias when d/a ratios at markers are used to estimate d/a ratios at QTL. Convergent improvement led to positive responses to selection when only 30 QTL controlled the trait. When 250 QTL controlled the trait, convergent improvement led to a positive response when the d scale was 30% but not when the d scale was 60%. For the intermediate d scale of 45%, responses were positive in later backcross generations and when prediction accuracy was 0.60 or 0.80. The largest response was achieved with only one cycle of genomewide recurrent selection; additional cycles compromised the gains achieved from the final step of phenotypic selection among single crosses. Overall, the results suggested that success in convergent improvement is a possibility but not a certainty in maize, and that more consistent results would be expected in species such as rice (Oryza sativa L.) that show weaker heterosis than maize.</p>","PeriodicalId":22955,"journal":{"name":"Theoretical and Applied Genetics","volume":"138 2","pages":"42"},"PeriodicalIF":4.4,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143075527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}