FHB resistance conferred by Fhb1 is under inhibitory regulation of two genetic loci in wheat (Triticum aestivum L.).

KEY MESSAGE: Two loci inhibiting Fhb1 resistance to Fusarium head blight were identified through genome-wide association mapping and validated in biparental populations. Fhb1 confers Fusarium head blight (FHB) resistance by limiting fungal spread within spikes in wheat (type II resistance). However, not all lines with Fhb1 display the expected resistance. To identify genetic factors regulating Fhb1 effect, a genome-wide association study for type II resistance was first performed with 72 Fhb1-carrying lines using the Illumina 90 K iSelect SNP chip. Of 84 significant marker-trait associations detected, more than half were repeatedly detected in at least two environments, with the SNPs distributed in one region on chromosome 5B and one on chromosome 6A. This result was validated in a collection of 111 lines with Fhb1 and 301 lines without Fhb1. We found that these two loci caused significant resistance variations solely among lines with Fhb1 by compromising the resistance. In1, the inhibitory gene on chromosome 5B, was in close linkage with Xwgrb3860 in a recombinant inbred line population derived from Nanda2419 × Wangshuibai and a double haploid (DH) population derived from R-43 (Fhb1 near isogenic line) × Biansui7 (with Fhb1 and In1); and In2, the inhibitory gene on chromosome 6A, was mapped to the Xwgrb4113-Xwgrb4034 interval using a DH population derived from R-43 × PH8901 (with Fhb1 and In2). In1 and In2 are present in all wheat-growing areas worldwide. Their frequencies in China's modern cultivars are high but have significantly decreased in comparison with landraces. These findings are of great significance for FHB resistance breeding using Fhb1.

Mass Spectrometry Imaging of Lipids in the Scent Glands of Muskrat (Ondatra zibethicus) in Different Reproductive Statuses.

As a typical seasonal breeding animal, male muskrats have a pair of scent glands that can emit musky odor substances to attract females during the breeding period. The present study aimed to visualize the differences in the distribution of lipids in the scent glands of muskrats during their different reproductive statuses by imaging mass spectrometry and quantitative real-time PCR (qRT-PCR). The results revealed remarkable differences in the expression and spatial distribution of lipids detected in the scent glands of muskrats during the different reproductive statuses. In addition, the expression levels of lipid molecules PC (32:0) and LysoPC (16:0) were found to be significantly higher in the breeding season than in the non-breeding season. Moreover, the mRNA expression levels of lipid synthesis enzyme Pemt and Pla2g4b were higher in the breeding season than in the non-breeding season, and there were positive correlations between the expression intensities of lipid molecules and the expression levels of Pemt and Pla2g4b. The present study investigates the changes and distribution of the endogenous lipid in the scent glands of muskrats and elucidates that the seasonal changes in the lipid metabolism may affect the functions of the scent glands in muskrats.

Learning curve and short-term outcomes of modularized LADG for advanced gastric cancer: A retrospective study.

Laparoscopy-assisted distal gastrectomy (LADG) is a complicated procedure. To reduce the difficulty of the operation and standardize the surgical procedure, we explored a new operation mode, which we termed modularized LADG (MLADG). To further extend the new operation mode, we conducted this study to evaluate the short-term outcomes of MLADG for advanced gastric cancer, and determine the learning curve.Data from 100 consecutive patients who received LADG between October 2016 and October 2017 were retrospectively analyzed. Short-term outcomes, such as operation time and intraoperative blood loss, were evaluated, and the learning curve was calculated.For MLADG, the mean operation time was 168.2 ±â€Š13.0 minutes, the mean intraoperative blood loss was 93.6 ±â€Š29.1 ml, the mean number of harvested lymph nodes was 28.6 ±â€Š4.2, and conversion to open surgery occurred in only 1 case. In addition, MLADG had an acceptable postoperative complication incidence and fast postoperative recovery. After the first 20 cases, the operation skill reached a mature and stable level.Our results indicate that MLADG is an oncologically feasible and technically safe surgical procedure. For the trainees with rich experience in open distal gastrectomy, the learning curve is considered to be completed after 20 MLADG cases.