Quantitative Insights into Grapevine Anthracnose () Epidemiology: Impact of Temperature and Leaf Age on Incubation, Lesion Development, and Sporulation.

Grapevine anthracnose, caused by , is one of the most devastating diseases for wine and table grapes, particularly in hot, humid regions. This study explores how temperature and leaf age affect incubation and how temperature affects lesion development and sporulation. The influence of temperature and leaf age on incubation period (days) was tested under controlled conditions.

Survey of Diversity Reveals as a Potential Phytophthora Root Rot Pathogen in Québec Christmas Tree Plantations.

Christmas trees are an economically and culturally important ornamental plant in North America. Many microorganisms are pathogens of firs cultivated as Christmas trees. Among those, causes millions of dollars in damage to plantations annually.

Genotyping by sequencing suggests overwintering of Peronospora destructor in southwestern Québec, Canada.

Several Peronospora species are carried by wind over short and long distances, from warmer climates where they survive on living plants to cooler climates. In eastern Canada, this annual flow of sporangia was thought to be the main source of Peronospora destructor responsible for onion downy mildew. However, the results of a recent study showed that the increasing frequency of onion downy mildew epidemics in eastern Canada is associated with warmer autumns, milder winters, and previous year disease severity, suggesting overwintering of the inoculum in an area where the pathogen is not known to be endogenous.

Detection and Quantification of and AG1-IB Causing the Bottom Rot of Lettuce in Tissues and Soils by Multiplex qPCR.

In the muck soil region of southwestern Quebec, vegetable growers are threatened by several soilborne diseases, particularly the bottom rot of lettuce caused by the fungus . The particularly warm temperature of the few last seasons was marked by an increase in disease severity, and the associated yield losses were significant for Quebec lettuce growers. In the absence of registered fungicides and resistant cultivars, the management of -induced diseases in lettuce is based on good agricultural practices, which require detailed knowledge of the pathogen.

A HRM Assay for Rapid Identification of Members of the Seedcorn Maggot Complex (Delia florilega and D. platura) (Diptera: Anthomyiidae) and Evidence of Variation in Temporal Patterns of Larval Occurrence.

The seedcorn maggot Delia platura (Meigen), and the bean seed maggot Delia florilega (Zetterstedt) can cause considerable feeding damage to a wide range of cultivated crops. The recent discovery of two distinct genetic lines of D. platura, each with a unique distribution pattern overlapping only in eastern Canada, suggests the presence of a new cryptic species for the group.

Monitoring of Primary and Secondary Inoculum by Real-Time qPCR.

Onion downy mildew (ODM), caused by , is a serious threat for onion growers worldwide. In southwestern Québec, Canada, a steady increase in occurrence of ODM has been observed since the mid-2000s. On onion, can develop local and systemic infections producing numerous sporangia which act as initial inoculum locally and also for neighboring areas.

Soilborne Inoculum Density and Environmental Parameters Influence the Development of Pythium Stunt Caused by in Head Lettuce Crops.

In Quebec muck soils, Pythium stunt ( Matta) is responsible for important yield losses in head lettuce crops each year, which can reach up to 50% in certain cases. Despite the significance of the disease, factors influencing its development remain poorly documented, and no disease risk indicators are available, which makes the development of management strategies difficult. Hence, growers systematically use chemical fungicides throughout the growing season to reduce crop losses.

Detection and Quantification of Pythium tracheiphilum in Soil by Multiplex Real-Time qPCR.

In Canada, head lettuce (Lactuca sativa capitata) is extensively produced in the muck soils of southwestern Québec. However, yields are increasingly affected by various soilborne pathogens, including Pythium spp., which cause wilt and damping off.

Host Range and Genetic Characterization of Ditylenchus dipsaci Populations from Eastern Canada.

The stem and bulb nematode, Ditylenchus dipsaci, is a plant-parasitic nematode affecting over 500 plant species worldwide. Since 2012, garlic producers from Ontario and Quebec have been particularly affected with economic losses caused by this pest. Reproduction of D.

Development of Real-Time Isothermal Amplification Assays for On-Site Detection of Phytophthora infestans in Potato Leaves.

Real-time loop-mediated isothermal amplification (LAMP) and recombinase polymerase amplification (RPA) assays were developed targeting the internal transcribed spacer 2 region of the ribosomal DNA of Phytophthora infestans, the potato late blight causal agent. A rapid crude plant extract (CPE) preparation method from infected potato leaves was developed for on-site testing. The assay's specificity was tested using several species of Phytophthora and other potato fungal and oomycete pathogens.

A Quantitative Dynamic Simulation of Bremia lactucae Airborne Conidia Concentration above a Lettuce Canopy.

Lettuce downy mildew, caused by the oomycete Bremia lactucae Regel, is a major threat to lettuce production worldwide. Lettuce downy mildew is a polycyclic disease driven by airborne spores. A weather-based dynamic simulation model for B.

Infection Efficiency of Four Phytophthora infestans Clonal Lineages and DNA-Based Quantification of Sporangia.

The presence and abundance of pathogen inoculum is with host resistance and environmental conditions a key factor in epidemic development. Therefore, several spore-sampling devices have been proposed to monitor pathogen inoculum above fields. However, to make spore sampling more reliable as a management tool and to facilitate its adoption, information on infection efficiency and molecular tools for estimating airborne sporangia concentration are needed.

A pyrosequencing-based method to quantify genetic substitutions associated with resistance to succinate dehydrogenase inhibitor fungicides in Botrytis spp. populations.

Background: The genetic underlying resistance mechanisms in the population of the phytopathogenic fungus Botrytis cinerea are well documented. Specifically, several genetic substitutions associated with succinate dehydrogenase inhibitor (SDHI)-based fungicide resistance have been identified in the succinate dehydrogenase gene. The objective of the present work was to develop a molecular tool for accurate quantification of these genetic substitutions within Botrytis populations.