The corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), is an invasive insect that can cause damage to maize (Zea mays L.) in two ways: by direct feeding and the transmission of several plant pathogens. Dalbulus maidis is an invasive and serious economic pest of maize that has spread from its center of origin in Mexico to the southernmost parts of the United States. Prior to 2024, corn leafhoppers had not been documented in Oklahoma, and their spread northward toward the United States corn belt is of significant concern. Here, we provide the first reports of the insect in maize in several Oklahoma counties. Insect specimens were collected at various commercial and experimental field sites by Oklahoma State University research and extension personnel. The identity of the insect species was validated through morphological and molecular taxonomy. The presence records for the corn leafhopper presented here provide valuable information for future monitoring and management efforts of this economically important pest and disease.

Vascular streak dieback (VSD) poses a significant threat to the sustainability of woody ornamentals in the United States, particularly Cercis spp. (redbud). This study aimed to develop reliable molecular diagnostic tools for detecting Ceratobasidium sp. D.P. Rogers (Csp), the fungus consistently detected from VSD-symptomatic redbuds and other woody ornamentals. Molecular markers can provide rapid and accurate detection for fastidious fungi such as Csp that are challenging to recover in culture media. However, current molecular tools for Csp detection lack sensitivity and specificity. To address this, specific PCR and quantitative PCR (qPCR) primers were developed, targeting the internal transcribed spacer (ITS) genetic region. The existing primers for the second-largest subunit of RNA polymerase II (RPB2), translation elongation factor 1-alpha (TEF1-α), and ATP synthase subunit 6 (ATP6) genetic regions of Rhizoctonia fungi were also redesigned to enhance the sensitivity and accuracy of detection for Csp. The CP-qP-Csp primer set, with a detection limit of 86.02 pg/μl, effectively detected Csp in VSD-symptomatic tissues, cultures, and soils and is recommended for molecular detection of Csp from woody ornamentals in the U.S. Cross-platform validation across seven laboratories confirmed the robustness of the assays. These findings provide nursery producers with critical early-detection capabilities, potentially preventing significant economic losses and contributing to the sustainability of woody ornamental production. Future research will focus on refining these assays for field applications and exploring the genetic characteristics of Csp across different hosts and pathogen interactions to better understand the epidemiology of VSD.

Chrysanthemum (Chrysanthemum × morifolium) plants exhibiting stem and foliage blight were observed in a commercial nursery in eastern Oklahoma in June 2019. Disease symptoms were observed on ~10% o...