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Key Message: The HaOr5 resistance gene is located in a large genomic insertion containing putative resistance genes and provides resistance to O. cumana, preventing successful connection to the sunflower root vascular system. Orobanche cumana (sunflower broomrape) is a parasitic plant that is part of the Orobanchaceae family and specifically infests sunflower crops. This weed is an obligate parasitic plant that does not carry out photosynthetic activity or develop roots and is fully dependent on its host for its development. It produces thousands of dust-like seeds per plant. It possesses a high spreading ability and has been shown to quickly overcome resistance genes successively introduced by selection in cultivated sunflower varieties. The first part of its life cycle occurs underground. The connection to the sunflower vascular system is essential for parasitic plant survival and development. The HaOr5 gene provides resistance to sunflower broomrape race E by preventing the connection of O. cumana to the root vascular system. We mapped a single position of the HaOr5 gene by quantitative trait locus mapping using two segregating populations. The same location of the HaOr5 gene was identified by genome-wide association. Using a large population of thousands of F2 plants, we restricted the location of the HaOr5 gene to a genomic region of 193 kb. By sequencing the whole genome of the resistant line harboring the major resistance gene HaOr5, we identified a large insertion of a complex genomic region containing a cluster of putative resistance genes., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Key Message: A new Or Anom1 gene introgressed in cultivated sunflower from wild Helianthus anomalus confers late post-attachment resistance to Orobanche cumana race G and maps to a target interval in Chromosome 4 where two receptor-like kinases (RLKs) have been identified in the H. anomalus genome as putative candidates. Sunflower broomrape is a parasitic weed that infects sunflower (Helianthus annuus L.) roots causing severe yield losses. Breeding for resistance is the most effective and sustainable control method. In this study, we report the identification, introgression, and genetic and physiological characterization of a new sunflower source of resistance to race G of broomrape developed from the wild annual sunflower H. anomalus (accession PI 468642). Crosses between PI 468642 and the susceptible line P21 were carried out, and the genetic study was conducted in BC 1 F 1 , BC 1 F 2, and its derived BC 1 F 3 populations. A BC 1 F 5 germplasm named ANOM1 was developed through selection for race G resistance and resemblance to cultivated sunflower. The resistant trait showed monogenic and dominant inheritance. The gene, named Or Anom1 , was mapped to Chromosome 4 within a 1.2 cM interval and co-segregated with 7 SNP markers. This interval corresponds to a 1.32 Mb region in the sunflower reference genome, housing a cluster of receptor-like kinase and receptor-like protein (RLK-RLP) genes. Notably, the analysis of the H. anomalus genome revealed the absence of RLPs in the Or Anom1 target region but featured two RLKs as possible Or Anom1 candidates. Rhizotron and histological studies showed that Or Anom1 determines a late post-attachment resistance mechanism. Broomrape can establish a vascular connection with the host, but parasite growth is stopped before tubercle development, showing phenolic compounds accumulation and tubercle necrosis. ANOM1 will contribute to broadening the genetic basis of broomrape resistance in the cultivated sunflower pool and to a better understanding of the molecular basis of the sunflower-broomrape interaction., (© 2024. The Author(s).)

Key Message: This study compares five models of GWAS, to show the added value of non-additive modeling of allelic effects to identify genomic regions controlling flowering time of sunflower hybrids. Genome-wide association studies are a powerful and widely used tool to decipher the genetic control of complex traits. One of the main challenges for hybrid crops, such as maize or sunflower, is to model the hybrid vigor in the linear mixed models, considering the relatedness between individuals. Here, we compared two additive and three non-additive association models for their ability to identify genomic regions associated with flowering time in sunflower hybrids. A panel of 452 sunflower hybrids, corresponding to incomplete crossing between 36 male lines and 36 female lines, was phenotyped in five environments and genotyped for 2,204,423 SNPs. Intra-locus effects were estimated in multi-locus models to detect genomic regions associated with flowering time using the different models. Thirteen quantitative trait loci were identified in total, two with both model categories and one with only non-additive models. A quantitative trait loci on LG09, detected by both the additive and non-additive models, is located near a GAI homolog and is presented in detail. Overall, this study shows the added value of non-additive modeling of allelic effects for identifying genomic regions that control traits of interest and that could participate in the heterosis observed in hybrids.

Rectal cancer continues to be a surgical challenge. As more technology is developed, the surgeon must both incorporate this new technology into his practice and, at the same time, keep improving oncologic surgery and overall outcomes. We describe a standardized approach and fully robotic proctectomy, using four arms and one single docking (SI system). Patient cart and ports placement, as well as arms position to avoid collision, are key points to perform the entire procedure with one single docking. Although the place of robotic surgery might still need to be defined, standardizing the procedures is a step towards its evaluation. We propose with this report a solution to perform a single docking four arms robotic proctectomy.

Background: Robotic total mesorectal excision (R-TME), a novel way for minimally invasive treatment of rectal cancer, was shown in previous studies to be safe and effective. However, comparison with laparoscopic total mesorectal excision (L-TME) has drawn contradictory disputes, especially concerning operative high-risk patients. The aim of this study was to compare R-TME and L-TME on the rectal technical approach., Methods: Between October 2009 and March 2013, a total of 120 consecutive rectal carcinomas, operated for sphincter-saving procedure, were enrolled. The patient population included the last 60 laparoscopic procedures and the first 60 robotic surgeries (six hybrid approaches, then 54 full robotic surgeries). There were no exclusions., Results: Patients' baseline characteristics were similar in both the R-TME and L-TME groups. Outcomes were equivalent for blood loss (200 vs. 100 mL), postoperative hospital stay (12 vs. 11 days), conversion rate (3.2 vs. 4.8 %), lymph nodes yield (15 vs. 19), no positive distal margin (0 %), positive radial margin (6.4 vs. 9.3 %), diverting ileostomy (73 vs. 58 %) and severe morbidity (28 vs. 20 %). Significant differences were found for median operative time (274 vs. 228 min; p = 0.003) and proctectomy performed via transanal approach (1.7 vs. 16.7 %; p = 0.004). The R-TME operative time curve stabilized to 245 min after the first 25 procedures., Conclusions: For rectal cancer, R-TME may be as feasible and safe as L-TME in terms of technique. In our practice and for difficult cases, R-TME allows complete rectal dissection by an abdominal approach, while L-TME requires a transanal approach.