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Common wheat (Triticum aestivum L.) is the most important crop in the world and a typical allopolyploid with a large and complex genome. Pre-harvest sprouting (PHS) leads to a significant reduction in grain quality worldwide. PHS is a complex trait with related QTL located on different chromosomes. However, the study of markers and genes related to PHS resistance is limited especially for whitegrained wheat. Four pairs of near isogenic lines (NILs) from a white-grained wheat cross of Chara x DM5637B*8 targeting a major QTL for PHS resistance (Qphs.ccsu-3A.1) on wheat chromosme 3AL were genotyped using the 90K SNP Illumina iSelect array. Ten SNPs were identified, with a 75%-100% consistency between genotype and phenotype in the resistant or susceptible isolines. The 10 SNPs were converted to cost-effective kompetitive allele-specific PCR (KASP) markers. Screening of 48 wheat cultivars with different phenotypes of PHS identified four KASP markers with 81.3%-85.4% conformity between genotype and phenotype. Further investigation revealed that the four SNPs (BS00022245_51, Kukri_c49927_151, BS00022884_51 and BS00110550_51) corresponding to the four validated KASP markers are residing in three independent genes (TraesCS3A03G1072800, TraesCS3A03G1072400, TraesCS3A03G1071800) close to each other with a distance of 4.28-4.48 Mb to the targeted QTL. These three annotated genes have potential functions related to PHS resistance. Our study revealed that combined use of NILs and the 90K SNP chip is a powerful approach for developing KASP markers and mining functional genes in wheat. The KASP markers for PHS resistance on chromosome 3AL are useful for high-throughput evaluation and marker-assisted selection, and the three identified genes could lead to a better understanding of the genetic pathways controlling PHS. [ABSTRACT FROM AUTHOR]

In monocropping systems autotoxins, such as phenolic compounds, could accumulate in soil and affects the soil microbial communities, however, the specific effects on microbial species are unknown. We determined the responses of cucumber rhizosphere Fusarium and Bacillus spp. communities to exogenously applied p-coumaric acid (0.02, 0.05, 0.1, 0.2 μmol/g soil) by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) technique. Results showed that all concentrations of p-coumaric acid changed the community structure of Fusarium spp. and p-coumaric acid at 0.2 μmol/g soil decreased the number of bands as indicated by Shannon-Wiener and evenness index of Fusarium spp. community. However, p-coumaric acid did not affect the structure of Bacillus spp. community. These results indicated that the p-coumaric acid showed different effects on Fusarium and Bacillus spp. communities. [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluated the performance of the Abbott BinaxNOW, a rapid severe acute respiratory syndrome coronavirus 2 antigen detection immunoassay in symptomatic children. Results indicate that the accuracy of the test was higher in children below seven years of age. It recommends the need to consider high rates of false-positives and the age of the target populations before using it as a stand-alone assay.