Risk Evaluation of Benzovindiflupyr Resistance of Verticillium dahliae Population in Maine.

Verticillium dahliae causes Verticillium wilt, resulting in significant losses to potato production. Benzovindiflupyr, a succinate dehydrogenase inhibitor, effectively controls V. dahliae. However, frequent applications of the chemical may expedite the development of fungicide resistance in the pathogen population. To evaluate the risk of benzovindiflupyr resistance, 38 V. dahliae strains were obtained from diseased potatoes in Maine. The sensitivity of the field population was determined based on effective concentration for 50% inhibition (EC50), which ranged from 0.07 to 11.28 µg ml-1 with a median of 1.08. Segregated clusters of EC50 values indicated that Maine V. dahliae populations have developed benzovindiflupyr resistance. By exposing conidia of V. dahliae to a high concentration of benzovindiflupyr, 18 benzovindiflupyr-resistant mutants were obtained. To examine their fitness, the mutants were continuously subculture-transferred for up to 10 generations. Mycelial growth, conidial production, competitiveness, pathogenicity, and cross resistance of the 10th generation mutants were examined. Results showed that 50% of the resistant mutants retained an adaptive level in mycelial growth, and 60% maintained conidial production similar to their parents. Pathogenicity did not change for any of the mutants. No cross resistance was detected between benzovindiflupyr and either azoxystrobin, boscalid, fluopyram, or pyrimethanil. Thus, the resistance risk in V. dahliae to benzovindiflupyr should be considered in Maine potato production.

Everything Is Faster: How Do Land-Grant University-Based Plant Diagnostic Laboratories Keep Up with a Rapidly Changing World?

Plant diagnostic laboratories (PDLs) are at the heart of land-grant universities (LGUs) and their extension mission to connect citizens with research-based information. Although research and technological advances have led to many modern methods and technologies in plant pathology diagnostics, the pace of adopting those methods into services at PDLs has many complexities we aim to explore in this review. We seek to identify current challenges in plant disease diagnostics, as well as diagnosticians' and administrators'perceptions of PDLs' many roles. Surveys of diagnosticians and administrators were conducted to understand the current climate on these topics. We hope this article reaches researchers developing diagnostic methods with modern and new technologies to foster a better understanding of PDL diagnosticians' perspective on method implementation. Ultimately, increasing researchers' awareness of the factors influencing method adoption by PDLs encourages support, collaboration, and partnerships to advance plant diagnostics.