Identification of quantitative trait loci associated with leaf rust resistance in rye by precision mapping.

BACKGROUND: Leaf rust (LR) is among the most destructive fungal diseases of rye (Secale cereale L.). Despite intensive research using various analytical and methodological approaches, such as quantitative trait locus (QTL) mapping, candidate gene expression analysis, and transcriptome sequencing, the genetic basis of the rye immune response to LR remains unclear. RESULTS: A genome-wide association study was employed to detect QTLs controlling the immune response to LR of rye. A mapping population, G38A, was constructed by crossing two inbred lines: 723 (susceptible to LR) and JKI-NIL-Pr3 (a donor of the LR resistance gene Pr3). For genotyping, SNP-DArT and silico-DArT markers were used. Resistance phenotyping was conducted by visual assessment of the infection severity in detached leaf segments inoculated with two isolates of Puccinia recondita f. sp. secalis, namely, 60/17/2.1 (isolate S) in the main experiment and 86/n/2.1_5x (isolate N) in the validation experiment, at 10 and 17 days post-infection (dpi), respectively. In total, 42,773 SNP-DArT and 105,866 silico-DArT markers were included in the main analysis including isolate S, of which 129 and 140 SNP-DArTs and 767 and 776 silico-DArTs were significantly associated (p ≤ 0.001; - log10(p) ≥ 3.0) with the immune response to LR at 10 and 17 dpi, respectively. Most significant markers were mapped to chromosome 1R. The number of common markers from both systems and at both time points occupying common chromosomal positions was 37, of which 21 were positioned in genes, comprising 18 markers located in exons and three in introns. This gene pool included genes encoding proteins with a known function in response to LR (e.g., a NBS-LRR disease resistance protein-like protein and carboxyl-terminal peptidase). CONCLUSION: This study has expanded and supplemented existing knowledge of the genetic basis of rye resistance to LR by (1) detecting two QTLs associated with the LR immune response of rye, of which one located on the long arm of chromosome 1R is newly detected, (2) assigning hundreds of markers significantly associated with the immune response to LR to genes in the 'Lo7' genome, and (3) predicting the potential translational effects of polymorphisms of SNP-DArT markers located within protein-coding genes.

Comparison of Distal Radius Autograft Technique with Iliac Crest Autograft Technique in Solitary Finger Enchondromas.

Objectives: The purpose of the study was to compare clinical and radiological outcomes of autografts obtained from the iliac crest (IC) and distal radius (DR) and to evaluate their superiority for surgical treatment of solitary finger enchondromas. Methods: Twenty-five patients for whom curettage and autografting were carried out for finger enchondroma were retrospectively analyzed. DR autograft was used in eight patients and IC autograft was used in 17 patients. Data on pre-operative total active motion (TAM), disabilities of the arm, shoulder, and hand (DASH) score, and pain visual analog scale (VAS) scores of the involved finger, duration of surgery, amount of bleeding during the operation, length of hospital stay, presence of complications related to anesthesia, and post-operative donor site morbidity were obtained. Pre-operative and post-operative 12th month radiographies were evaluated for pre-operative tumor volume, post-operative remnant volume, and Tordai radiologic evaluation grade. Results: No statistically significant difference could be identified between post-operative TAM (p=0.154), DASH (p=0.458), pain VAS scores (p=0.571), remnant volume (p=0.496), Tordai radiologic evaluation grade (p=0.522), duration of surgery (p=0.288), and amount of bleeding (p=0.114) between DR and IC groups. However, mean hospital stay duration was shorter for the DR group (p=0.0001). Recurrence was observed in one patient in the DR group and three patients in the IC group (p=0.996). Conclusion: The clinical and radiological outcomes of grafting from the DR and IC were similar in the treatment of hand enchondromas. However, grafting from the DR may result in shorter hospital stay compared to IC grafting.