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Summary: The role of cysteine‐rich secretory proteins, antigen 5, and pathogenesis‐related 1 (CAP) superfamily proteins in the innate immune responses of mammals is well characterized. However, the biological function of CAP superfamily proteins in plant–microbe interactions is poorly understood.We used proteomics and transcriptome analyses to dissect the apoplastic effectors secreted by the oomycete Phytophthora sojae during early infection of soybean leaves. By transiently expressing these effectors in Nicotiana benthamiana, we identified PsCAP1, a novel type of secreted CAP protein that triggers immune responses in multiple solanaceous plants including N. benthamiana. This secreted CAP protein is conserved among oomycetes, and multiple PsCAP1 homologs can be recognized by N. benthamiana.PsCAP1‐triggered immune responses depend on the N‐terminal immunogenic fragment (aa 27–151). Pretreatment of N. benthamiana with PsCAP1 or the immunogenic fragment increases plant resistance against Phytophthora. The recognition of PsCAP1 and different homologs requires the leucine‐rich repeat receptor‐like protein RCAP1, which associates with two central receptor‐like kinases BRI1‐associated receptor kinase 1 (BAK1) and suppressor of BIR1‐1 (SOBIR1) in planta.These findings suggest that the CAP‐type apoplastic effectors act as an important player in plant–microbe interactions that can be perceived by plant membrane‐localized receptor to activate plant resistance. [ABSTRACT FROM AUTHOR]

Plant pathogens rely on effector proteins to suppress host innate immune responses and facilitate colonization. Although the Phytophthora sojae RxLR effector Avh241 promotes Phytophthora infection, the molecular basis of Avh241 virulence remains poorly understood. Here we identified non‐race specific disease resistance 1 (NDR1)‐like proteins, the critical components in plant effector‐triggered immunity (ETI) responses, as host targets of Avh241. Avh241 interacts with NDR1 in the plasma membrane and suppresses NDR1‐participated ETI responses. Silencing of GmNDR1s increases the susceptibility of soybean to P. sojae infection, and overexpression of GmNDR1s reduces infection, which supports its positive role in plant immunity against P. sojae. Furthermore, we demonstrate that GmNDR1 interacts with itself, and Avh241 probably disrupts the self‐association of GmNDR1. These data highlight an effective counter‐defense mechanism by which a Phytophthora effector suppresses plant immune responses, likely by disturbing the function of NDR1 during infection. [ABSTRACT FROM AUTHOR]

The herbicides in naked oat (Avena nuda L.) samples were extracted, separated, and determined by using ionic‐liquid‐based matrix solid‐phase dispersion‐solvent flotation coupled with high‐performance liquid chromatography. The experimental parameters were optimized and evaluated by a univariate method and orthogonal experiment. A good linear relationship was obtained in the range of 5–5000 µg/kg, and the linear correlation coefficient are between 0.9989∼0.9993. The quantification limits for alachlor, metazachlor, propanil, acetochlor, pretilachlor, metolachlor, and butachlor are 5.03, 2.62, 2.73, 4.58, 7.28, 5.05, 5.78 µg/kg, respectively. The average recoveries of the acetanilide herbicides at spiked concentrations of 10, 100, and 500 µg/kg ranged from 92.1 to 104.7%, and relative standard deviations were equal to or lower than 2.9%. [ABSTRACT FROM AUTHOR]

Front Cover: Extraction of acetanilide herbicides in naked oat (Avena nuda L.) by using ionic-liquid-based matrix solid-phase dispersion-foam flotation solid-phase extraction The cover picture shows the extraction and separation effects of seven acetanilide herbicides in naked oat ( I Avena nuda L i .) In the extraction procedure, the ionic liquid-based matrix solid phase dispersion-foam flotation solid phase extraction was developed and applied in real oat samples. [Extracted from the article]