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Russian wheat aphid (Diuraphis noxia Kurdjumov [RWA]) is one of the most invasive and detrimental pests, and host plant resistance is the most efficient approach to manage RWA. Wheat (Triticum aestivum L.) accessions resistant to RWA biotype 1 (RWA1) and biotype 2 (RWA2) were previously identified by screening wheat accessions available at the USDA‐ARS National Small Grains Collection. However, RWA biotypic variation necessitates a continuous search for sources of resistance to new RWA biotypes. The objective of this study was to identify wheat accessions resistant to all major RWA biotypes in the United States. A set of 172 RWA‐resistant wheat accessions, mainly Iranian landraces, were evaluated for responses to five predominant U.S. biotypes—RWA1, RWA2, RWA3, RWA6, and RWA8—in controlled environments. Of these, 137 accessions showed homogeneous or heterogeneous resistance to at least one biotype, and 14 of them were resistant or highly resistant to all five biotypes. Another set of 19 accessions were resistant or highly resistant to two to four biotypes. These RWA‐resistant accessions are valuable sources for RWA resistance improvement, and further purification of some accessions and characterization of the underlying RWA resistance genes are imperative for their utilization in wheat breeding. [ABSTRACT FROM AUTHOR]

Key message: A new powdery mildew resistance gene that can be readily used in wheat breeding, Pm65, was identified in the facultative wheat cultivar Xinmai 208 and mapped to the terminal region of chromosome 2AL. Wheat powdery mildew, a widely occurring disease caused by the biotrophic fungus Blumeriagraminis f. sp. tritici (Bgt), poses a serious threat to wheat production. A high breeding priority is to identify powdery mildew resistance genes that can be readily used either alone or in gene complexes involving other disease resistance genes. An F2 population and 227 F2:3 families derived from the cross Xinmai 208 × Stardust were generated to map a powdery mildew resistance gene in Xinmai 208, a high-yielding Chinese wheat cultivar. Genetic analysis indicated that Xinmai 208 carries a single dominant powdery mildew resistance gene, designated herein Pm65, and linkage analysis delimited Pm65 to a 0.5 cM interval covering 531.8 Kb (763,289,667–763,821,463 bp) on chromosome 2AL in the Chinese Spring reference sequence. An allelism test indicated that Pm65 is a new gene about 10.3 cM distal to the Pm4 locus. Pm65 was 0.3 cM proximal to Xstars355 and 0.2 cM distal to Xstars356. It conferred near-immunity to 19 of 20 Bgt isolates collected from different wheat-growing regions of the USA. Coming from a high-yield potential cultivar, Pm65 can be directly used to enhance powdery mildew resistance in wheat. The newly developed SSR markers Xstars355 and Xstars356 have the potential to tag Pm65 for wheat improvement. [ABSTRACT FROM AUTHOR]

Key message: A new powdery mildew resistance gene conferring a wide spectrum of resistance toBgtisolates in the USA,Pm63, was identified in Iranian wheat landrace PI 628024 and mapped to the terminal region of the long arm of chromosome 2B. Powdery mildew is a globally important wheat disease causing severe yield losses, and host resistance is the preferred strategy for managing this disease. The objective of this study was to characterize a powdery mildew resistance gene in Iranian landrace PI 628024, which exhibited a wide spectrum of resistance to representative Blumeria graminis f. sp. tritici (Bgt) isolates collected from different regions of the USA. An F2 population and F2:3 lines derived from the cross PI 628024 × CItr 11349 were used in this study, and genetic analysis indicated that a single dominant gene, designated Pm63, conferred resistance to Bgt isolate OKS(14)-B-3-1. Linkage analysis located Pm63 to an interval of about 13.1 Mb on the long arm of chromosome 2B, spanning 710.3–723.4 Mb in the Chinese Spring reference sequence. Bin mapping assigned Pm63 to the terminal bin 2BL6-0.89-1.0, 1.1 cM proximal to STS marker Xbcd135-2 and 0.6 cM distal to SSR marker Xstars419. Allelism tests indicated that Pm63 is a new powdery mildew resistance gene, which differs from other genes in the terminal bin by origin, genomic location, and responses to a set of 16 representative US Bgt isolates. Pm63 can be widely used to enhance powdery mildew resistance in the Great Plains, western, and southeastern regions of the USA. [ABSTRACT FROM AUTHOR]

Anesthetic ketamine is a racemic mixture containing equal amount of (R)-ketamine and (S)-ketamine. Increasing preclinical data show that (R)-ketamine has a rapid-onset and sustained antidepressant without significant side effects. There are currently many studies on (R)-ketamine, however, the quantity and quality of these studies are unknown. Therefore, we conducted a bibliometric analysis of research on (R)-ketamine from January 2002 to December 2021. We obtained the publications on (R)-ketamine from the Web of Science database during the period. A variety of bibliographic elements were collected, including annual publications, authors, countries/regions, institutions, journals, and keywords. A total of 922 publications were included in this study. Professor Kenji Hashimoto of Chiba University in Japan was the most productively influential author in the field of (R)-ketamine and the authors from United States were the leader in this field. In addition, we found that the antidepressant effect of (R)-ketamine has been a hotspot in very recent years. This study provided a comprehensive analysis of research on (R)-ketamine and highlighted the growing interest in (R)-ketamine and its antidepressant effects., Competing Interests: Declaration of competing interest Dr. Hashimoto is the inventor of filed patent applications on “The use of R-ketamine in the treatment of psychiatric diseases”, “(S)-norketamine and salt thereof as pharmaceutical”, “R-ketamine and derivative thereof as prophylactic or therapeutic agent for neurodegeneration disease or recognition function disorder”, “Preventive or therapeutic agent and pharmaceutical composition for inflammatory diseases or bone diseases”, “R-ketamine and its derivatives as a preventive or therapeutic agent for a neurodevelopmental disorder”, and “TGF-β1 in the treatment of depression” by the Chiba University. Dr. Hashimoto has also received speakers’ honoraria, consultant fee, or research support from Abbott, Daiichi-Sankyo, Meiji Seika Pharma, Seikagaku Corporation, Dainippon-Sumitomo, Taisho, Otsuka, Murakami Farm and Perception Neuroscience. The other authors declared no conflicts of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)