Basal stalk rot (BSR), caused by the ascomycete fungus Sclerotinia sclerotiorum (Lib.) de Bary, is a serious disease of sunflower (Helianthus annuus L.) in the cool and humid production areas of the world. Quantitative trait loci (QTL) for BSR resistance were identified in a sunflower recombinant inbred line (RIL) population derived from the cross HA 441 ´ RHA 439. A genotyping-bysequencing (GBS) approach was adapted to discover single nucleotide polymorphism (SNP) markers. A genetic linkage map was developed comprised of 1053 SNP markers on 17 linkage groups (LGs) spanning 1401.36 cM. The RILs were tested in five environments (locations and years) for resistance to BSR. Quantitative trait loci were identified in each environment separately and also with integrated data across environments. A total of six QTL were identified in all five environments: one of each on LGs 4, 9, 10, 11, 16, and 17. The most significant QTL, Qbsr-10.1 and Qbsr-17.1, were identified at multiple environments on LGs 10 and 17, explaining 31.6 and 20.2% of the observed phenotypic variance, respectively. The remaining four QTL, .1, were detected in only one environment on LGs 4, 9, 11, and 16, respectively. Each of these QTL explains between 6.4 and 10.5% of the observed phenotypic variation in the RIL population. Alleles conferring increased resistance were contributed by both parents. The potential of the Qbsr-10.1 and Qbsr-17.1 in marker-assisted selection (MAS) breeding are discussed. Sclerotinia sclerotiorum (Lib.) de Bary is a necrotrophic fungus with a vast host range of >400 broadleaf species (Boland and Hall, 1994). The fungus causes three distinctly different diseases on sunflower: BSR or wilt, midstalk rot (MSR), and head rot. This fungal pathogen is characterized by its ability to produce long-term survival structures called sclerotia, which individually consist of masses of hyphae surrounded by a hard, black, protective rind. Depending on environmental conditions, sclerotia can germinate myceliogenically, and cause root infection, or carpogenically, producing apothecia then ascospores and infect aboveground parts of host plants (Gulya et al., 1997;Bolton et al., 2006). Unlike other hosts, BSR symptoms start from a root infection resulting from myceliogenic germination of sclerotia. Midstalk rot commonly begins as a leaf infection, while head rot infection begins on capitula. Both MSR and head rot symptoms are incited by airborne ascospores Univ., Fargo, ND 58102, USA. Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the USDA. The USDA is an equal opportunity provider and employer.

The morphology and structure of wax crystals are among the factors dominating rheological characteristics of a waxy crude oil at temperatures below the wax appearance temperature (WAT). In several reported researches fractal dimensions were employed in describing the waxy crude oil microstructures; however, they were all determined via the indirect approach, i.e. deduced from the rheological data. This paper presents a direct fractal characterization approach based on micrographs of wax crystals. The box-counting method is applied to the wax crystal images of three waxy crude oils beneficiated with and without pour-point-depressants (PPDs), and for the fractal measurements the t-distribution tests of hypothesis on linear regression are performed at the significance level of 0.01. It is demonstrated that the boundary fractal dimensions from micrographs of different visual fields of a specimen are almost identical, with the maximum and minimum relative ranges being 9.97% and 1.88% respectively, and with the standard deviation ranging from 0.0549 to 0.0107. Then the wax crystal structures are determined as fractal at the confidence level of 99%. All the listed absolute t-statistics with the minimum of 29.568 are much higher than the corresponding t-quantiles with the maximum of 3.4995. The results also show that the larger value of the boundary box dimension represents the higher complexity and irregularity of the wax crystal morphology. The box dimension increases with decreasing oil temperature for each waxy crude oil. After the oil is beneficiated with a PPD, the box dimension increases at each given temperature. Thus, it is feasible to use fractal dimensions to characterize the waxy crude oil microstructures. This helps to probe the rheology–microstructure relation.

Commercial hybrid seed production in sunflower currently relies on a single cytoplasmic male sterility (CMS) source, PET1 and the major fertility restoration gene, Rf1, leaving the crop highly vulnerable to issues with genetic bottlenecks. Therefore, having multiple CMS/Rf systems is important for sustainable sunflower production. Here, we report the identification of a new fertility restoration gene, Rf7, which is tightly linked to a new downy mildew (DM) resistance gene, Pl34, in the USDA sunflower inbred line, RHA 428. The Rf7 gene was genetically mapped to an interval of 0.6 cM on the lower end of linkage group (LG) 13, while Pl34 was mapped 2.1 cM proximal to the Rf7. Both the genes are located in a cluster of Rf and Pl genes. To gain further insights into the distribution of Rf genes in the sunflower breeding lines, we used a genome-wide association study (GWAS) approach to identify markers associated with the fertility restoration trait in a panel of 333 sunflower lines genotyped with 8,723 single nucleotide polymorphism (SNP) markers. Twenty-four SNP markers on the lower end of LG13 spanning a genomic region of 2.47 cM were significantly associated with the trait. The significant markers were surveyed in a world collection panel of 548 sunflower lines and validated to be associated with the Rf1 gene. The SNP haplotypes for the Rf1 gene are different from Rf5 and the Rf7gene located in the Rf gene cluster on LG13. The SNP and SSR markers tightly flanking the Rf7 gene and the Pl34 gene would benefit the sunflower breeders in facilitating marker assisted selection (MAS) of Rf and Pl genes.

Sunflower (Helianthus annuus L.) production is challenged by different biotic and abiotic stresses, among which downy mildew (DM) is a severe biotic stress that is detrimental to sunflower yield and quality in many sunflower-growing regions worldwide. Resistance against its infestation in sunflower is commonly regulated by single dominant genes. Pl17 and Pl19 are two broad-spectrum DM resistance genes that have been previously mapped to a gene cluster spanning a 3.2 Mb region at the upper end of sunflower chromosome 4. Using a whole-genome resequencing approach combined with a reference sequence-based chromosome walking strategy and high-density mapping populations, we narrowed down Pl17 to a 15-kb region flanked by SNP markers C4_5711524 and SPB0001. A prospective candidate gene HanXRQChr04g0095641 for Pl17 was identified, encoding a typical TNL resistance gene protein. Pl19 was delimited to a 35-kb region and was approximately 1 Mb away from Pl17, flanked by SNP markers C4_6676629 and C4_6711381. The only gene present within the delineated Pl19 locus in the reference genome, HanXRQChr04g0095951, was predicted to encode an RNA methyltransferase family protein. Six and eight SNP markers diagnostic for Pl17 and Pl19, respectively, were identified upon evaluation of 96 diverse sunflower lines, providing a very useful tool for marker-assisted selection in sunflower breeding programs.

Using 219 F 2 individuals developed by crossing the genetic standard line TM-1 and the multiple dominant marker line T586 in Gossypium hirsutum L., a genetic linkage map with 19 linkage groups was constructed based on simple sequence repeat (SSR) markers. Compared with our tetraploid backboned molecular genetic map from a (TM-1×Hai 7124)×TM-1 BC 1 population, 17 of the 19 linkage groups were combined and anchored to 12 chromosomes (sub-genomes). Of these groups, four morphological marker genes in T586 had been mapped into the molecular linkage map. Meanwhile, three quantitative trait loci for lint percentage were tagged and mapped separately on the A03 linkage group and chromosome 6. TZ (2006). Molecular tagging and mapping of quantitative trait loci for lint percentage and morphological marker genes in upland cotton. J Integrat Plant Biol 48(3), 320−326.The development of a genetic linkage map is a basic step to investigate genome structure, organization, and evolution, to identify quantitative traits loci (QTL) that influence the performance of agronomic traits and facilitate marker-assisted selection in a plantbreeding program, and to control the expression of economically important traits and perform map-based gene cloning. Using morphological markers and a series of aneuploid cottons, a genetic map consisting of 18 linkage groups was constructed, in which 12 linkage groups were associated with the corresponding chromosomes (Endrizzi et al. 1985). Using molecular marker technology, several cotton genetic maps have been reported (Reinisch et al.

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BackgroundRefractory blood loss is a common problem in surgeries for acute type A aortic dissections. Significant evidence has supported the benefit of using recombinant activated factor VII (rFVIIa) to control of intractable bleeding in patients after cardiac surgery. In this prospective clinical study, we present a novel method to achieve intraoperative hemostasis by using a combination of platelets and rFVIIa during operations for acute type A aortic dissections.MethodsBetween May 2009 and August 2012, 71 patients with acute type A dissections who underwent emergency surgery were prospectively included and allocated to one of the following two intervention groups for hemostasis: 3 units platelets combined with 2.4 mg rFVIIa (n = 25), and conventional methods (n = 46).ResultsThe patients who received the combination of platelets and rFVIIa required fewer transfusions of red blood cells (6.2 ± 3.1 units vs 9.8 ± 2.8 units; p < 0.05), fresh frozen plasma (736.9 ± 178.3 ml vs 1264.3 ± 245.2 ml, p < 0.05), platelet concentrates (3 units vs 5.0 ± 1.8 units, p < 0.001), and cryoprecipitate (2.8 ± 0.9 units vs 8.2 ± 2.3 units, p < 0.05). These patients also required less time for sternal closure (76.9 ± 17.2 min vs 102.3 ± 10.7 min, p < 0.05) compared with the conventional therapy patients. There was no statistically significant difference in the incidence of serious adverse events between these two groups.ConclusionsUsing a combination of platelets and rFVIIa is an effective strategy for achieving hemostasis during acute type A dissection surgery. This hemostatic strategy does not appear to be associated with an increase in postoperative adverse events.Electronic supplementary materialThe online version of this article (doi:10.1186/s13019-014-0156-y) contains supplementary material, which is available to authorized users.

Sclerotinia head and stalk rots are among the most devastating diseases in sunflower (Helianthus annuus L.). Breeding for resistance to these diseases while maintaining or improving yield and quality is complicated by the quantitative inheritance of the resistance, for which there are few genes of major effect. The objective of this work was to provide new diversity to sunflower breeding organizations for yield and Sclerotinia resistance, together with other useful agronomic and end user traits. Four restorer germplasms, RHA 461 (Reg. No. GP‐337, PI 655012), RHA 462 (Reg. No. GP‐338; PI 655013), RHA 463 (Reg. No. GP‐339; PI 655014), and RHA 468 (Reg. No. GP‐341; PI 667184), and three maintainer germplasms, HA 465 (Reg. No. GP‐342; PI 670488), HA 466 (Reg. No. GP‐340; PI 667183), and HA 467 (Reg. No. GP‐343; PI 670489) were developed by the USDA‐ARS and the North Dakota Agricultural Experiment Station, Fargo, ND. Testcrosses with these germplasms had yield similar to high‐yielding commercial checks and Sclerotinia resistance similar to the highly resistant check ‘Northrup King 277’. Some of the lines also have high oleic acid in the seed oil, downy mildew resistance, and tolerance to imidazolinone herbicides. The lines are available for sunflower breeders to integrate into their breeding programs for additional diversity.