Summary: Drought and Verticillium wilt disease are two main factors that limit cotton production, which necessitates the identification of key molecular switch to simultaneously improve cotton resistance to Verticillium dahliae and tolerance to drought stress. R2R3‐type MYB proteins could play such a role because of their conserved functions in plant development, growth, and metabolism regulation, however, till date a MYB gene conferring the desired resistance to both biotic and abiotic stresses has not been found in cotton. Here, we describe the identification of GhMYB36, a gene encoding a R2R3‐type MYB protein in Gossypium hirsutum, which confers drought tolerance and Verticilium wilt resistance in both Arabidopsis and cotton. GhMYB36 was highly induced by PEG‐simulated drought stress in G. hirsutum. GhMYB36‐silenced cotton plants were more sensitive to both drought stress and Verticillium wilt. GhMYB36 overexpression in transgenic Arabidopsis and cotton plants gave rise to improved drought tolerance and Verticillium wilt resistance. Transient expression of fused GhMYB36‐GFP in tobacco cells was able to localize GhMYB36 in the cell nucleus. In addition, RNA‐seq analysis together with qRT‐PCR validation in transgenic Arabidopsis overexpressing GhMYB36 revealed significantly enhanced PR1 expression. Luciferase interaction assays indicated that GhMYB36 are probably bound to the promoter of PR1 to activate its expression and the interaction, which was further verified by Yeast one hybrid assay. Taken together, our results suggest that GhMYB36 functions as a transcription factor that is involved in drought tolerance and Verticillium wilt resistance in Arabidopsis and cotton by enhancing PR1 expression.

Introduction: Phytophthora sojae is among the most devastating pathogens of soybean (Glycine max) and severely impacts soybean production in several countries. The resulting disease can be difficult to diagnose and other Phytophthora species can also infect soybean. Accurate diagnosis is important for management of the disease caused by P. sojae.Methods: In this study, recombinase polymerase amplification (RPA) in combination with the CRISPR/Cas12a system were used for detection of P. sojae. The assay was highly specific to P. sojae.Results: The test results were positive for 29 isolates of P. sojae, but negative for 64 isolates of 29 Phytophthora species, 7 Phytopythium and Pythium species, 32 fungal species, and 2 Bursaphelenchus species. The method was highly sensitive, detecting as little as 10 pg.µL⁻¹ of P. sojae genomic DNA at 37°C in 20 min. The test results were visible under UV light and readout coming from fluorophores. In addition, P. sojae was detected from natural inoculated hypocotyls of soybean seedlings using this novel assay. The rapidity and accuracy of the method were verified using 30 soybean rhizosphere samples.Discussion: In conclusion, the RPA-CRISPR/Cas12a detection assay developed here is sensitive, efficient, and convenient, and has potential for further development as a kit for monitoring root rot of soybean in the field.

Introduction: Phytophthora ramorum is a quarantine pathogen that causes leaf blight and shoot dieback of the crown, bark cankers and death on a number of both ornamental and forest trees, especially in North America and northern Europe, where it has produced severe outbreaks. Symptoms caused by P. ramorum can be confused with those by other Phytophthora and fungal species. Early and accurate detection of the causal pathogen P. ramorum is crucial for effective prevention and control of Sudden Oak Death.Methods: In this study, we developed a P. ramorum detection technique based on a combination of recombinase polymerase amplification (RPA) with CRISPR/Cas12a technology (termed RPACRISPR/ Cas12a).Results: This novel method can be utilized for the molecular identification of P. ramorum under UV light and readout coming from fluorophores, and can specifically detect P. ramorum at DNA concentrations as low as 100 pg within 25 min at 37°C.Discussion: We have developed a simple, rapid, sensitive, unaided-eye visualization, RPA CRISPR/Cas12a-based detection system for the molecular identification of P. ramorum that does not require technical expertise or expensive ancillary equipment. And this system is sensitive for both standard laboratory samples and samples from the field.

Background: The Catharanthus roseus receptor-like kinase 1-like (CrRLK1L) subfamily, a specialized group within receptor-like kinases (RLKs), was initially identified in C. roseus cell cultures. CrRLK1L plays an important role in the growth, development and stress response of plants. Although CrRLK1L genes have been characterized across multiple plant species, their biological and genetic functions in potatoes (Solanum tuberosum) remains poorly elucidated. Methods: a genome-wide investigation, phylogenetic analysis, chromosome localization, exon–intron structure, conserved motifs, stress-responsive cis-elements, tissue-specific expression patterns, and their effects on pathogen associated molecular patterns (PAMPs) induced reactive oxygen species (ROS) production were analyzed. Results: A total of 29 CrRLK1L genes were identified in the S. tuberosum genome, unevenly distributed across 10 chromosomes and divided into three groups. Tissue-specific expression analysis revealed seven genes highly expressed in all tissues, while CrRLK1L13 was specific to stamens and flowers. Under stress conditions (mannitol, salt, hormone, and heat), StCrRLK1L genes exhibited diverse expression patterns. Functional characterization in Nicotiana benthamiana identified seven ROS suppressors and four ROS enhancers, implicating their roles in PAMP-triggered immunity. Conclusions: This study provides valuable insights into the StCrRLK1L gene family, enhancing our understanding of its functions, particularly in plant innate immunity.

Verticillium dahliae is a broad host-range phytopathogenic fungus that causes destructive vascular wilt on plants worldwide. Cytochrome P450 monooxygenases, also known as CYPs/P450s, are broadly distributed in organisms and are involved in a diverse array of molecular/metabolic processes. In this study, using reverse transcription quantitative PCR analysis, we observed that the expression of a P450 gene (Chr2g00380) in the E-class P450, group IV from V. dahliae isolate JR2 was highly induced during tomato infection. Targeted deletion of Chr2g00380 in JR2 did not affect hyphal growth and morphology; however, the mutants exhibited increased sensitivity to H₂O₂ and defects in melanized microsclerotia formation compared with the wild type. Loss of Chr2g00380 resulted in reduced virulence on tomato and tobacco plants but did not cause phenotypic changes in infection structure formation or in the penetration of cellophane membranes. These data provide evidence for an involvement of a cytochrome P450 monooxygenase in virulence in V. dahliae.