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Maize, a one of the cereal crops, serves as the staple food for numerous people across the world. Maize breeding programmes primarily aim to enhance the yield potential of newly developed cultivars. This objective can be accomplished either by direct selection for increased grain yield or by indirect selection for traits closely associated with yield. The present study was carried out in two environments viz., Coimbatore (E1) and Vagarai (E2) to locate QTLs associated with yield-related traits in a recombinant inbred line (RIL) population that resulted from a cross between UMI79 and UMI 936(w). A total of seven yield-related traits (Ear weight, ear diameter, ear length, kernel row number, kernel number per row, 100-kernel weight, and grain yield) were evaluated across the two environments. The QTLs were mapped with the support of genotyping-by-sequencing based SNPs genetic linkage map which contains 1516 markers and spans 10 chromosomes and covers an overall distance of 6924.7 centimorgans. A total of 22 QTLs were discovered across these environments and best linear unbiased predictors, with four of these QTLs being common across them. The study pinpointed three stable QTLs (qEW-6, qEL-2, and qKRN-5), each contributing > 10% of the phenotypic variance in ear weight, ear length, and kernel row number, respectively. Within these QTL regions, 109 protein-coding genes were identified. Gene ontology analysis revealed these genes roles in development, reproduction, and growth. Several candidate genes, including MADS-box transcription factors, serine carboxypeptidase, and E3 ubiquitin-protein ligase, are well known for their role in yield-related traits of maize, and other cereal crops were among those identified. These findings provide valuable information for maize breeders aiming to enhance grain yield-related traits through marker-assisted breeding. [ABSTRACT FROM AUTHOR]

Among a vast number of polymorphisms in the wheat genome, of special interest are those that are markers for loci under selection. Such loci include storage protein loci, which directly determine the level of bread-making quality, and disease resistance genes. In this study we analyzed diversity of functional markers (seven storage protein loci and three disease resistance genes) in the group of East European winter common wheat genotypes (cultivars and lines of Poltava breeding). Using the UPGMA or NJ methods, the cultivars and lines were divided into two clusters differing in the Glu-1 quality score. The cultivars of cluster 1 with the lower mean Glu-1 quality score predominantly carried the combination of alleles Glu-B1c, Glu-D1a, and Gli-B1e, as well as the resistance allele of Lr34, whereas those of cluster 2 with the higher quality score mainly had the alleles Glu-B1u, Glu-D1d, and Gli-B1b. In the sample of Poltava cultivars, a high correlation between the Glu-1 quality score and the sedimentation value (0.84) was observed. On average for two years, the group of cultivars from cluster 1 showed higher grain protein content and some spike traits in comparison with the means of the sample from cluster 2. Significant associations of Lr34 alleles and alleles at some storage protein loci were revealed, in particular, the association of the resistance allele Lr34R and the allele Glu-D1a in both cultivar and line groups, indicating the adaptive value of such a combination for local soil and climate conditions. [ABSTRACT FROM AUTHOR]

Super Basmati is an elite variety with extra-long grains and superior quality but its yield is severely affected by water stress. Recombinant inbred lines (RILs) developed from the cross of Super Basmati and IR55419-04 (a coarse grained variety with high yield potential) were used to identify and map yield-related quantitative trait loci (QTLs) under normal field conditions. Genotypes for 244 KASP markers were obtained from 188 F9 RILs and a linkage map constructed of 1369.4 cM, with average marker interval of 10.5 cM. Eleven agronomic traits were phenotyped in RILs and parents. Composite interval mapping and inclusive composite interval mapping model identified 21 common QTLs related to nine agronomic traits; of the QTLs identified, twelve mapped at novel positions. LOD scores ranged from 2.51 for number of filled grains (qFG1.1) to 16.8 for plant height (qPH1.1). Four major effect QTLs could explain 20% of variation related for plant height, hundred-grain weight and grain width. Alleles from IR55419-04 improved grain filling, grain weight and grain width, while alleles from Super Basmati contributed to longer grains, panicles and flag leaves. Putative candidate genes were identified for 18 yield-related QTLs. These results validate the use of KASP genotyping for QTL mapping of yield-related traits in a bi-parental segregating population. SNPs in the QTLs identified in this study can be used in marker assisted selection for yield components to improve Basmati rice. [ABSTRACT FROM AUTHOR]

Key message: Common loci and candidate genes for controlling salt-alkali tolerance and yield-related traits were identified in Brassica napus combining QTL mapping with transcriptome under salt and alkaline stresses. The yield of rapeseed (Brassica napus L.) is determined by multiple yield-related traits, which are susceptible to environmental factors. Many yield-related quantitative trait loci (QTLs) have been reported in Brassica napus; however, no studies have been conducted to investigate both salt-alkali tolerance and yield-related traits simultaneously. Here, specific-locus amplified fragment sequencing (SLAF-seq) technologies were utilized to map the QTLs for salt-alkali tolerance and yield-related traits. A total of 65 QTLs were identified, including 30 QTLs for salt-alkali tolerance traits and 35 QTLs for yield-related traits, accounting for 7.61–27.84% of the total phenotypic variations. Among these QTLs, 18 unique QTLs controlling two to four traits were identified by meta-analysis. Six novel and unique QTLs were detected for salt-alkali tolerance traits. By comparing these unique QTLs for salt-alkali tolerance traits with those previously reported QTLs for yield-related traits, seven co-localized chromosomal regions were identified on A09 and A10. Combining QTL mapping with transcriptome of two parents under salt and alkaline stresses, thirteen genes were identified as the candidates controlling both salt-alkali tolerance and yield. These findings provide useful information for future breeding of high-yield cultivars resistant to alkaline and salt stresses. [ABSTRACT FROM AUTHOR]

Drought is a worldwide problem seriously influencing sugarcane (Saccharum L. spp. hybrids) production. The long-term domestication and selective breeding in artificial environments may have reduced the drought resistance of sugarcane. The objective of this study was to determine drought tolerance in a 138-genotype of elite sugarcane hybrids using the membership function value of drought tolerance (MFVD). Based on the drought-tolerant coefficient (DC) of four yield traits (biomass, stalk weight, stalk diameter and stalk height) and bud survival rate (SR) at different growth stage under well-watered (WW) and water-stressed (WS) conditions. As expected, genotype means decreased for all five traits with WS, and the decrease of biomass, stalk weight, stalk diameter, stalk height and bud survival rate (SR) was ≥ 24%. The broad sense heritability of five morphological traits (B, SW, SH, SD and SR) was relatively high. Correlation coefficients analysis revealed that the MFVD was significantly positively correlated with the DCB, DCSW, DCSH and DCSD at the growth stage and SR at the seedling stage. Results indicated that these characters were closely related to the drought resistance of sugarcane. Regression models built based on MFVD indicated that the variation of drought tolerant coefficient of 4 traits at the growth stage and SR at the seeding stage could explain the total variation. Thus, these five traits could be used as drought resistance indicators for screening drought resistance cultivars in sugarcane. The MFVD based on the DC of each yield traits and SR indicated that ten out of the138 sugarcane hybrids had high drought resistance, while 14 genotypes were highly susceptible to the drought, which can be used as ideal experimental materials to study the mechanism of sugarcane genotypes with contrasting drought sensitivities in response to drought stress. Our results help to fill the knowledge gap regarding to the sugarcane production under stress, shed light on sugarcane drought tolerance and provided useful information to the sugarcane breeders and producers which could be used in variety selecting and developing for dry prone regions. [ABSTRACT FROM AUTHOR]

Asian cultivated rice (Oryza sativa L.) has two subspecies, indica and japonica, which display clear differences in yield-related traits and environmental adaptation. Here, we developed a set of chromosome segment substitution lines (CSSLs) from an advanced backcross between japonica variety C418, as the recipient, and indica variety IR24, as the donor. Through evaluating the genotypes and phenotypes of 181 CSSLs, a total of 85 quantitative trait loci (QTLs) for 14 yield-related traits were detected, with individual QTLs explaining from 6.2 to 42.9% of the phenotypic variation. Moreover, twenty-six of these QTLs could be detected in the two trial sites (Beijing and Hainan). Among these loci, the QTLs for flag leaf width and effective tiller number, qFLW4.2 and qETN4.2, were delimited to an approximately 256-kb interval on chromosome 4. Through a comparison of nucleotide sequences and expression levels in "C418" and the CSSL CR31 containing qFLW4.2 and qETN4.2, we found that the NAL1 (LOC_Os04g52479) gene was the candidate gene for qFLW4.2 and qETN4.2. Our results show that CSSLs are powerful tools for identifying and fine-mapping QTLs, while the novel QTLs identified in this study will also provide new genetic resources for rice improvement. [ABSTRACT FROM AUTHOR]

As one of the important spike components, spikelet number is closely related to wheat yield. In the present study, a major stable QTL for spikelet number per spike (SNPS), qSnps-7D, was identified using a recombinant inbred line mapping population derived from the cross between Kenong 9204 (KN9204) and Jing 411 (J411) (KJ-RILs). To decipher its genetic effects on yield-related traits and selection effects in wheat breeding process, phenotype data together with genotype data from KJ-RILs and a natural mapping population were collected. qSnps-7D was mapped to the interval of 1.63 Mb on chromosome 7D in the KN9204 genome assembly in 4 of the 6 datasets. The favored alleles from KN9204 could significantly increase SNPS, kernel number per spike (KNPS). The diagnostic markers for SNPS were further developed and validated. The selection utilization rate of the favored haplotype in foreign varieties was lower than that in China, and it showed an increasing trend with time passage, with the ratio reaching more than 50% since the 1990s. In addition, loci for yield-related traits co-located with qSnps-7D were sorted out. Meanwhile, the relationship between SNPS and its components as well as other important yield-related traits were also discussed. Taken together, the studies will lay foundation for gene cloning and molecular breeding utilization of qSnps-7D. [ABSTRACT FROM AUTHOR]

A predominant objective in wheat breeding is improving yield-related traits. The homeodomain-leucine zipper (HD-Zip) transcription factor plays a significant role in plant growth and development. In this study, we cloned all homeologs of TaHDZ34, which is a member of the HD-Zip class IV transcription factor family in wheat (Triticum aestivum L.). Sequence polymorphism analysis showed that TaHDZ-A34, TaHDZ-B34, and TaHDZ-D34 formed five, six, and six haplotypes, respectively, and the genes were divided into two main haplotype groups. We also developed functional molecular markers. The TaHDZ34 genes were divided into eight main haplotype combinations. Association analysis and distinct population validation preliminarily indicated that TaHDZ34 genes modulate grain number per spike, effective spikelet number per spike, thousand kernel weight, and flag leaf area per plant in wheat. Hap-ABD was the most effective haplotype combination of TaHDZ34. Subcellular localization showed that TaHDZ-A34 was localized to the nucleus. The interacting proteins of TaHDZ-A34 were involved in protein synthesis/degradation, energy production and transportation, and photosynthesis. Geographic distribution and frequencies of TaHDZ34 haplotype combinations suggested that Hap-Abd and Hap-AbD were preferentially selected in Chinese wheat breeding programs. The high-yield-related haplotype combination Hap-ABD provided beneficial genetic resources for the marker-assisted selection of new wheat cultivars. [ABSTRACT FROM AUTHOR]

The surveys were performed to analyze the adaptive capacity in the spring barley varieties bred at the Rudnitsky Federal Agricultural Science Center of the Northeast (FANC Northeast) for the yield-related traits and the antifungal resistance. The surveys were carried out in Kirov oblast in 2018–2021. Nine in-demand spring barley varieties bred in 1992 to 2021 served as the survey material. Statistical parameters bi and were assessed with the methods of S.A. Eberhart and W.A. Russell (1966) in the interpretation of V.A. Zykin et al. (1984). The adaptive coefficient (AC) was estimated with the method developed by L.A. Zhivotkova et al. (1994). The individual responses of the analyzed barley varieties to the environments were identified. The most high-yielding variety was the new Boyarin cultivar (5.7 t/ha), while the least-productive variety was the Ecolog cultivar (4.4 t/ha). The Tandem (bi = 1.32; = 0.27) and Boyarin (bi = 0.89; = 0.34) cultivars are intensive varieties with a broad reaction norm and a high productive potential. They tend to respond to environment improvement, while they are characterized by ecological instability. Therefore, they should be sown in the most favorable years at the high-level agricultural-system reference. Plasticity and high adaptive capacity are typical for the cultivars Novichok (bi = 1.22 and = 0.05), Rodnik Prikamya (bi = 1.10 and = 0.02), and Dobryak (bi = 1.34 and = 0. 001). They may be sown in more complex agroecological systems, where they can provide maximum economic efficiency at minimum costs. The best immunological status was recorded in cultivars Pamyaty Rodinoy, Dobryak, Boyarin, and new promising lines 52-12 and 94-13. In addition, a reliable (at P ≥ 0.95) negative effect on the components of plant yield performance was recorded only in case of the net blotch occurrence (r = –0.42...–0.73). [ABSTRACT FROM AUTHOR]

Foxtail millet (Setaria italica) is an ideal model of genetic system for functional genomics of the Panicoideae crop. Identification of QTL responsible for morpho-agronomic and yield-related traits facilitates dissection of genetic control and breeding in cereal crops. Here, based on a Yugu1 × Longgu7 RIL population and genome-wide resequencing data, an updated linkage map harboring 2297 bin and 74 SSR markers was constructed, spanning 1315.1 cM with an average distance of 0.56 cM between adjacent markers. A total of 221 QTL for 17 morpho-agronomic and yield-related traits explaining 5.5 ~ 36% of phenotypic variation were identified across multi-environments. Of these, 109 QTL were detected in two to nine environments, including the most stable qLMS6.1 harboring a promising candidate gene Seita.6G250500, of which 70 were repeatedly identified in different trials in the same geographic location, suggesting that foxtail millet has more identical genetic modules under the similar ecological environment. One hundred-thirty QTL with overlapping intervals formed 22 QTL clusters. Furthermore, six superior recombinant inbred lines, RIL35, RIL48, RIL77, RIL80, RIL115 and RIL125 with transgressive inheritance and enrichment of favorable alleles in plant height, tiller, panicle morphology and yield related-traits were screened by hierarchical cluster. These identified QTL, QTL clusters and superior lines lay ground for further gene-trait association studies and breeding practice in foxtail millet. [ABSTRACT FROM AUTHOR]

Chromosome segment substitution line (CSSL) is important for functional analysis and design breeding of target genes. Here, a novel rice CSSL-Z431 was identified from indica restorer line Xihui18 as recipient and japonica Huhan3 as donor. Z431 contained six segments from Huhan3, with average substitution length of 2.12 Mb. Compared with Xihui18, Z431 increased panicle number per plant (PN) and displayed short-wide grains. The short-wide grain of Z431 was caused by decreased length and increased width of glume cell. Then, thirteen QTLs were identified in secondary F2 population from Xihui18/Z431. Again, eleven QTLs (qPL3, qPN3, qGPP12, qSPP12, qGL3, qGW5, qRLW2, qRLW3, qRLW5, qGWT3, qGWT5-2) were validated by six single-segment substitution lines (SSSLs, S1-S6) developed in F3. In addition, fifteen QTLs (qPN5, qGL1, qGL2, qGL5, qGW1, qGW5-1, qRLW1, qRLW5-2, qGWT1, qGWT2, qYD1, qYD2, qYD3, qYD5, qYD12) were detected by these SSSLs, while not be identified in the F2 population. Multiple panicles of Z431 were controlled by qPN3 and qPN5. OsIAGLU should be the candidate gene for qPN3. The short-wide grain of Z431 was controlled by qGL3, qGW5, etc. By DNA sequencing and qRT-PCR analysis, two best candidate genes for qGL3 and qGW5 were identified, respectively. In addition, pyramid of different QTLs in D1-D3 and T1-T2 showed independent inheritance or various epistatic effects. So, it is necessary to understand all genetic effects of target QTLs for designing breeding. Furthermore, these secondary substitution lines improved the deficiencies of Xihui18 to some extent, especially increasing yield per plant in S1, S3, S5, D1-D3, T1, and T2. [ABSTRACT FROM AUTHOR]

Background: Soybean (Glycinemax (L.) Merr.) is an economically important crop for vegetable oil and protein production, and yield is a critical trait for grain/vegetable uses of soybean. However, our knowledge of the genes controlling the vegetable soybean yield remains limited. Objective: To better understand the genetic basis of the vegetable soybean yield. Methods: The 100-pod fresh weight (PFW), 100-seed fresh weight (SFW), kernel percent (KP) and moisture content of fresh seeds (MCFS) at the R6 stage are four yield-related traits for vegetable soybean. We investigated a soybean mini core collection composed of 224 germplasm accessions for four yield-related traits in two consecutive years. Based on 1514 single nucleotide polymorphisms (SNPs), genome-wide association studies (GWAS) were conducted using a mixed linear model (MLM). Results: Extensive phenotypic variation existed in the soybean mini core collection and significant positive correlations were shown among most of traits. A total of 16 SNP markers for PFW, SFW, KP and MCFS were detected in all environments via GWAS. Nine SNP markers were repeatedly identified in two environments. Among these markers, eight were located in or near regions where yield-related QTLs have been reported in previous studies, and one was a novel genetic locus identified in this study. In addition, we conducted candidate gene analysis to the large-effect SNP markers, a total of twelve genes were proposed as potential candidate genes of soybean yield at the R6 stage. Conclusion: These results will be beneficial for understanding the genetic basis of soybean yield at the R6 stage and facilitating the pyramiding of favourable alleles for future high-yield breeding by marker-assisted selection in vegetable soybean. [ABSTRACT FROM AUTHOR]

Improving yield is one of the most important targets of sesame breeding. Identifying quantitative trait loci (QTLs) of yield-related traits is a prerequisite for marker-assisted selection (MAS) and QTL/gene cloning. In this study, a BC1 population was developed and genotyped with the specific-locus amplified fragment (SLAF) sequencing technology, and a high-density genetic map was constructed. The map consisted of 13 linkage groups, contained 3528 SLAF markers, and covered a total of 1312.52 cM genetic distance, with an average distance of 0.37 cM between adjacent markers. Based on the map, 46 significant QTLs were identified for seven yield-related traits across three environments. These QTLs distributed on 11 linkage groups, each explaining 2.34–71.41% of the phenotypic variation. Of the QTLs, 23 were stable QTLs that were detected in more than one environment, and 20 were major QTLs that explained more than 10% of the corresponding phenotypic variation in at least one environment. Favorable alleles of 38 QTLs originated from the locally adapted variety, Yuzhi 4; the exotic germplasm line, BS, contributed favorable alleles to only 8 QTLs. The results should provide useful information for future molecular breeding and functional gene cloning. [ABSTRACT FROM AUTHOR]

Yield improvement is an important target for rapeseed breeding. Resolving the genetic architecture of yield in Brassica napus, QTL analysis was carried out in a double haploid population derived from a cross between ZS11 and QU cultivars. A 60-K SNP chip was used to construct a genetic linkage map; a total of 5044 SNP markers were mapped to 19 linkage groups. QTLs of yield-related traits were mapped for seed density (SD), silique density on the main inflorescence (SDMI), thousand seed weight (TSW), and silique length (SL) in seven environments and 3 years experiments. Four major consensus QTLs of SD, TSW, and SL were identified in seven environments, explaining 48.06, 53.27, 37.13, and 52.13% of phenotypic variation, respectively. Two major consensus QTLs of SDMI were detected in six environments, explaining 13.32 and 11.76% of phenotypic variation, respectively. Notably, nine major consensus QTLs of SD, SDMI, TSW, and SL showed narrower confidence intervals (< 1 Mb). Moreover, two major pleiotropic QTLs controlling three traits (SD, TSW, and SL) simultaneously were identified, co-locating on 23.82–26.66 Mb, 27.06–28.53 Mb on chromosome A9 of B. napus, respectively. Most importantly, our research reveals the first (to our knowledge) pleiotropic QTLs, which controlled SD, TSW, and SL on chromosome A9 in B. napus. Furthermore, we found eight possible candidate genes might be related to SD, TSW, and SL, synchronously. Overall, these results lay a foundation for developing closely linked molecular markers, conducting fine mapping and gene cloning for yield-related traits in B. napus. [ABSTRACT FROM AUTHOR]

Saccharum spontaneum L. is an important wild used parent for sugarcane breeding, which can improve variety yield, ratoon ability and resistance to biotic and abiotic stress. In order to illustrate the genetic diversity of yield-related traits within a collection of S. spontaneum from Yunnan province, China, 222 clones from six geographic regions of Yunnan were screened for five yield-related traits. The results showed that: (1) the coefficient of variation (CV) of five yield-related traits ranged from 20.39 to 77.06%, of which the stalk weight exhibited the highest genetic variation with the highest CV value (77.06%), followed by the tillering rate with a CV value of 38.33%. The clones from the northwestern region of Yunnan exhibited the highest genetic variation, with an average CV value of 39.03%, followed by clones from the southwestern and southern regions; (2) the elevation and latitude of the locations from where the clones were collected had significant negative correlations with stalk height, stalk diameter and stalk weight ( p < 0.01), but there was a significant positive correlation between latitude and tillering rate; (3) among six populations, there was no obvious genetic divergence because of a small divergence coefficient (Gst = 5.18%) and high gene flow (Nm = 9.1587); and (4) based on the UPGMA cluster analysis of these clones, three groups with obvious difference in four traits were obtained. Finally, the top 15 ranked clones per trait were listed in the paper for innovation utilization. The results from this study will aid in the selection of high biomass clones as wild parents for improving variety yield potential and can provide direction for the collection and management plan of S. spontaneum resources of Yunnan. [ABSTRACT FROM AUTHOR]

Gossypium hirsutum L. is a widely cultivated species characterized by its high yield and wide environmental adaptability, while Gossypium barbadense is well known for its superior fiber quality. In the present report, we, for the first time, developed G. hirsutum chromosome segment introgression lines (ILs) in a G. barbadense background (GhILs_Gb) and genetically dissected the inheritance of lint yield and fiber quality of G. hirsutum in G. barbadense background. The GhILs_Gb contains introgressed segments spanning 4121.20 cM, which represents 82.20% of the tetraploid cotton genome, with an average length of 18.65 cM. A total of 39 quantitative trait loci (QTLs) for six traits are identified in this IL population planted in Xinjiang. Four QTL clusters are detected. Of them, however, three clusters have deleterious effects on fiber length and strength and boll weight, and only one cluster on Chr. D9 can be used in marker-assisted selection (MAS) to increase lint percentage and decrease micronaire value in G. barbadense. QTL mapping showed that most of yield-related QTLs detected have positive effects and increase lint yield in G. barbadense, while most of fiber quality-related QTLs have deleterious effects except for micronaire. It suggested that G. hirsutum evolved to have a high lint yield. Several lines improved in lint percentage and boll size in G. barbadense by introgressed one fragment of G. hirsutum have been developed from the GhILs_Gb. The ILs developed, and the analyses presented here will enhance the understanding of the genetics of lint yield and fiber quality in G. hirsutum and facilitate further molecular breeding to improve lint yield in G. barbadense. [ABSTRACT FROM AUTHOR]

Iron deficiency chlorosis (IDC) causes a significant reduction in yield of groundnut grown in calcareous and alkaline soils in India. The main aim of the study was to assess genotypic differences for morpho-physiological parameters associated with IDC resistance across different stages and their effect on yield and its related traits. The factorial pot experiment was comprised of two major factors, i) soil-Fe status [normal-Fe, deficit-Fe], and ii) genotypes [five] with differential IDC response, constituting 10 treatments. They were assessed for five morpho-physiological parameters associated with IDC resistance across five crop growth stages and also yield and its related traits. Associations between these traits were also estimated. Under deficit-Fe conditions, IDC resistant genotypes recorded significantly lower visual chlorosis rating (VCR), higher SPAD values, active Fe, chlorophyll content, peroxidase activity, and high yield compared to susceptible ones. Between normal- to deficit-Fe soils, resistant compared to susceptible genotypes showed no change in VCR scores; a lower reduction in SPAD, chlorophyll, active Fe, peroxidase activity, and pod yield. Under deficit-Fe conditions, high yield among resistant genotypes could be attributed to higher seed weight, number of pods and haulm yield, while contrasting reduction in main stem height and number of primaries. The results indicate that for initial large-scale screening of groundnut genotypes for IDC resistance, SPAD values are most ideal while active Fe could be utilized for confirmation of identified lines. [ABSTRACT FROM AUTHOR]

The pattern of the panicle is an important characteristic of sorghum that is used to identify race divisions and species values. The knowledge of the genetic basis of sorghum inflorescence architecture and its component traits can enhance the process of improvement in sorghum breeding. This study was undertaken to better understand the genetic basis of sorghum inflorescence architecture and its association with yield-related traits. We investigated 98 simple sequence repeat maps in the sorghum diversity research set (SDRS) of 107 landraces from the worldwide sorghum germplasm. A significant difference between accessions was observed for 14 measured traits. In several components of sorghum inflorescence architecture, we found that the significance and high correlations between pairs of traits revealed that these variations are dependent not only on the panicle length (PanL) but also on the total branch number, maximum length of the primary branch (MaxLBZ/MxLBZ) , rachis length (Rac), and panicle diameter (PanD) and width (Panw). Significant mean squares were obtained for almost all characters in the individual analysis and combined analysis of variance for each season and across two seasons, suggesting that, the components of inflorescence architecture and yield related traits were highly variable in SDRS population, therefore, would respond to selection for yield improvement. Molecular markers divided the germplasm into three sub-populations with different groups of inflorescence/panicle types (PanT) (broom, open and compact). The SDRS was composed of six different PanT that were associated with 14 inflorescence traits. Using different models of association analysis, 16 loci on 8 chromosomes were found to be significantly related to the patterns of observed panicle traits. Among these loci, four QTLs were responsible for length-based traits, and three QTLs were responsible for dimentional traits. Four QTLs were responsible for panicle feature such as PanT and shape, one QTL responsible for yield related trait such as grain weight. Two QTLs were responsible for branch-based traits, such as the total node number and branch number with −Log ( P) values ranging from 1.5 to 7.6 as the threshold value. Several genomic regions affected multiple traits, including one region that affected PanL and MxLBZ/MaxLBZ. QTLs for different traits tended to be found in the same region on chromosome 4 and on chromosome 9. Additionally, QTL was involved on Chr-2, Chr-5, Chr-6 and Chr-10 as a novel QTL that controlled Rac, total node number, PanD and PanT. These results will serve as preliminary findings of QTLs for sorghum inflorescence architecture, and a further evaluation of the germplasm for these traits is in progress. Moreover, these findings can lead to the emergence of a new era of sorghum genomics, which are aimed at bridging the knowledge gap between genotype and phenotype in sorghum inflorescence architecture. [ABSTRACT FROM AUTHOR]

This study was conducted to identify the quantitative trait loci (QTL) associated with grain yield and its related traits by analysis of 122 doubled haploid population derived from a cross between Korean wheat cultivars carried different yield potential. DH population was evaluated in replicated field trials in 2011/2012 and 2012/2013 at upland and paddy conditions in Iksan, Korea. Grain yield and its related traits, including days to heading and maturity, culm and spike length, spike number per m, kernel number per spike, and thousand kernel weight, were investigated. A genetic map was constructed with 140 microsatellite marker loci and a total of nine QTLs were identified on eight chromosomes for grain yield and its related traits. The three QTLs, Xgpw2206, Xgwm247, and Xwmc471, were detected on chromosomes 2A, 3A, and 3B, and explained 10.1-22.8 % of phenotypic variation for grain yield. Among these QTLs, Xgpw2206 and Xgwm247 explained 10.7-37.9 % of phenotypic variation for days to heading and maturity, spike length, spike number per m, and kernel number per spike. Other six QTLs on chromosomes 2D, 4A, 5A, 6A, and 7A accounted for 11.4-39.9 % of phenotypic variation for culm and spike length, spike number per m, and thousand kernel weight. Those three QTLs for grain yield were applied to validate relationship between genotypes of QTL and 25 Korean wheat cultivars. Korean wheat cultivars carried hha genotypes based on the order of those three QTLs, showed higher GY (664.4 kg/10a) than genotype bha (494.2 kg/10a). Those three QTLs could be used in marker-assisted selection to improve grain yield and its related traits in Korean wheat breeding programs. [ABSTRACT FROM AUTHOR]

Globe artichoke ( Cynara cardunculus var. scolymus), whose immature inflorescences ( capitula) are consumed as a vegetable all over the world, contributes significantly to the agricultural economy of the Mediterranean basin. Here, we describe a QTL (quantitative trait loci) analysis aimed at elucidating the mode of inheritance of seven main and first-order capitulum traits. Mapping was carried out in an F population obtained by crossing a globe artichoke with a cultivated cardoon ( C. cardunculus var. altilis). A total of 100 QTL associated with the seven capitulum traits were mapped to 23 chromosomal regions, scattered over 12 of the 17 linkage groups. Among these, 73 were expressed in both growing seasons, while the others were only detected in one season. Up to nine QTL per trait were identified, and major QTL, responsible for some 20 % of the phenotypic variation, were detected for capitulum length, diameter, shape index and fresh weight. The QTL for correlated traits frequently co-localized, most likely due to pleiotropy. This study represents the first report on yield traits QTL in globe artichoke. The QTL identified, along with linked markers, particularly those located in four hot-spot QTL regions are of practical interest for crop improvement based on marker-assisted breeding. [ABSTRACT FROM AUTHOR]

Evaluation of combining ability is a crucial process in hybrid breeding, and dissection of the genetic basis of combining ability will facilitate hybrid breeding. In this study, molecular markers significantly associated with general combining ability (GCA) of seven yield-related traits and the traits per se were detected in a set of maize introgression lines (ILs) under three environments. Totally 25 and 31 significant loci for GCA and the traits per se were commonly detected under multiple environments, respectively. Correlation analysis and comparison among these significant loci revealed that the genetic basis of GCA of these yield-related traits was generally different from that of the traits per se except for the trait of ear row number. In addition, GCA of the ILs was positively and significantly correlated to the total relative effects of significant GCA loci in the ILs in general, implying that the GCA loci identified in this study would be useful in molecular breeding. Correlation analysis also showed that the GCA of yield per plant was strongly correlated to the GCA of kernel number per row, ear length and 100-kernel-weight, thus these traits were more important in genetic improvement for GCA. Results in this study would provide useful information for hybrid breeding in maize. [ABSTRACT FROM AUTHOR]

Chinese cabbage ( Brassica rapa L. ssp. pekinensis) is one of the most important vegetables in China. However, the inheritance of yield-related traits in Chinese cabbage is poorly understood to date. To map quantitative trait loci (QTL) for yield-related traits in Chinese cabbage, a genetic linkage map was constructed with 192 doubled haploid (DH) lines. The genetic map was constructed based on 190 sequence-related amplified polymorphisms and 43 simple sequence repeats. QTL mapping was conducted for 11 yield-related traits in 170 DH lines derived from a cross between two diverse Chinese cabbage lines, 'WZ' and 'FT', under different environmental conditions. A total of 46 main QTL (M-QTL) and 7 epistatic QTL (E-QTL) were identified. The phenotypic variation explained by each M-QTL and E-QTL ranged from 4.85 to 25.06 % and 1.85 to 13.29 %, respectively. The QTL-by-environment interactions were detected using the QTLNetwork 2.0 program in joint analyses of multi-environment phenotypic values. The phenotypic variation explained by each QTL and by QTL × environment interaction was 1.14-4.24 % and 0.00-1.26 %, respectively. Our results provide a better understanding of the genetic factors controlling leaf and head-related traits in Chinese cabbage. [ABSTRACT FROM AUTHOR]

The new wheat germplasm 3228, a putative derivative of tetraploid Agropyron cristatum Z559 and the common wheat Fukuhokomugi, has superior features in yield-related traits, particularly in spike morphological traits, such as large spike and superior grain number. To identify favorable alleles of these traits in 3228, 237 F families were developed from the cross 3228/Jing 4839. A genetic map was constructed using 179 polymorphic SSR and EST-SSR markers. A total of 76 QTL controlling spike number per plant (SNP), spike length (SL), spikelet number per spike (SNS), floret number per spikelet (FNS), grain number per spike (GNS) and thousand-grain weight (TGW) were detected on 16 chromosomes. Each QTL explained 1.24-27.01% of the phenotypic variation, and 9 QTL (28.95%) were detected in two or all environments. Additive effects of 45 QTL were positive with 3228 alleles increasing the QTL effects, 31 QTL had negative effects indicating positive contributions from Jing 4839. Three important clusters involving all traits were located on chromosomes 5A, 6A and 4B, and several co-located QTL were also found. Most of the QTL detected on the three chromosome regions could contribute to the use of 3228 in breeding for grain yield improvement. [ABSTRACT FROM AUTHOR]

The advanced backcross quantitative trait locus (AB-QTL) analysis has proven its usefulness to identify and localize favourable alleles from exotic germplasm and to transfer those alleles into elite varieties. In a balanced design with up to six environments and two nitrogen fertilization (N treatment) levels, a 4-factorial mixed model analysis of variance (ANOVA) was used to identify QTL main effects, QTL × environment interaction effects and QTL × N treatment interaction effects in the spring barley BCDH population S42. The yield-related traits studied were number of ears per m, days until heading, plant height, thousand grain weight (TGW) and grain yield. In total, 82 QTLs were detected for all traits. This finding was compared to a previous QTL study of the same population S42, where the current field data was reduced to one half through restriction of the analysis to the standard N treatment level (von Korff et al., Theor Appl Genet 112: 1221-1231, ). These authors located 54 QTLs for the same traits by applying a 3-factorial mixed model similar to the current model but excluding the factor N treatment. We found that QTL × environment interaction, alone or in combination, accounted for 24 of the newly uncovered QTLs, whereas QTL × N treatment interaction was of lesser importance with six new cases in total. A valuable QTL interacting with N treatment has been identified on chromosome 7H where lines carrying the wild barley allele were superior in number of ears per m in either N treatment. We conclude that in population S42 the extension of the phenotype data set and the inclusion of N treatment into the mixed model increased the power of QTL detection by providing an additional replication rather than by revealing specific N treatment QTLs. [ABSTRACT FROM AUTHOR]

Rapeseed breeding programs are focused mainly on improving plant potential and seed yield. One of the ways to improve seed yield in oilseed rape is heterosis, which is hybrid vigor that results in a greater biomass, increased seed yield, and faster development. The purpose of this study was to estimate yield-related trait heterosis for single cross and three-way cross hybrids of winter oilseed rape (Brassica napus L.). A population of 60 doubled-haploid (DH) lines and two generations of hybrids were evaluated in field trials to assess six yield-related traits: plant height, number of branches per plant, number of siliques per plant, silique length, number of seeds per silique, and thousand seed weight. Heterosis effects for each trait were estimated by a comparison of the particular hybrid with: (1) the trait mean over both parents—mid-parent heterosis and (2) to the value of better parent—best-parent heterosis. Traits with clear positive heterosis and traits with varied heterosis were observed in this study. For the first group, we include plant height, silique length, and the number of seeds per silique—a large number of hybrids expressed significant positive heterosis for these traits, independent from the year of observations and the type of hybrid. For the second group, with varied heterosis, we can include the number of branches and siliques per plant and thousand seed weight. For these traits, hybrids exhibited both positive and negative significant heterosis, without a clear pattern for the years and types of hybrids. [ABSTRACT FROM AUTHOR]

Xiaoyan 6, one of the most important founder parents in wheat, possesses many superior agronomic traits and has played a crucial role in Chinese wheat breeding programs. In this study, a panel of 66 elite wheat accessions derived from Xiaoyan 6 was planted in four growing seasons; genome-wide association study (GWAS) was performed for six yield-related traits using the wheat 90K genotyping assay. A total of 803 significant marker-trait associations (MTAs) that explained up to 35.0% of the phenotypic variation were detected. Of these, the locus QTkw-5B which contains 19 MTAs for thousand kernel weight (TKW) was consistently detected in three growing seasons and confirmed in a recombinant inbred line (RIL) population by developing simple sequence repeats (SSR) and kompetitive allele-specific PCR (KASP) markers. The locus QPh-3A containing eight repetitive MTAs for plant height (PH) was consistently identified in all the four growing seasons and validated in a RIL population by developing SSR markers. The transmission of Xiaoyan 6 allele indicated that the favorite allele of QPh-3A was strongly selected in breeding programs. Comparing with previous studies, QTkw-5B and QPh-3A should be novel QTL. The locus QFss-2D for fertile spikelet number per spike (FSS) was identified and then validated in three bi-parental populations. This locus controlled various spike-related traits and may be a key spike polymorphic locus. This study could provide insight into dissecting yield-related traits in the breeding population and reliable molecular markers that might be valuable for marker-assisted selection in wheat high-yield breeding programs. [ABSTRACT FROM AUTHOR]