Biology

Spinach Downy Mildew Biofungicide Trials

Full analysis is here Published in Plant Disease Management Reports 2014, 2015, and 2016. Throughout my PhD work, it became obvious that the challenges of spinach downy mildew were most heavily impacting organic growers. They were unable to rely on conventional synthetic pesticides that were able to suitably control disease in the conventional crop, and had to rely on resistance to control the disease. I wanted to see if any biofungicide had effect on the disease.

Grape Powdery Mildew Variety Trials

Full analysis is here Published in Plant Disease Management Reports 2011, and 2012. UNDER CONSTRUCTION! The Results Conclusions

Powdery Mildew on Filaree

Full data and analysis here Publication here Powdery Mildew on Whitestem Filaree I was walking around my neighborhood in Davis, CA one day when I noticed a strange looking weed on the ground that had powdery mildew on it’s surface. Powdery mildews are a group of biotrophic fungi that I had studied for my master’s degree. They are often times host specific, and do not regularly kill their host, but rather sap nutrients and water from the epidermal cells.

Summary measures of predictive power associated with logistic regression models of disease risk

For an ordinary least squares regression model, the coefficient of determination R2 describes the proportion (or percentage) of variance of the response variable explained by the model, and is a widely-accepted summary measure of predictive power. A …

Bird Ages

Bird Age Full analysis is here I stumbled across a dataset of bird ages on a USGS website, and wanted to know if there was a relationship between bird age and other variables (weight, wingspan, etc). Link Between Bird Age and Phylogenetic Order? I wanted to know if there was any signal for how old birds get if theyre closely related. Ultimately, I would love to know how age is affected by size (weight, wingspan, whatever) but I cant find open datasets for that.

Climate change, carbon dioxide, and pest biology, managing the future: coffee as a case study

The challenge of maintaining sufficient food, feed, fiber, and forests, for a projected end of century population of between 9–10 billion in the context of a climate averaging 2–4 °C warmer, is a global imperative. However, climate change is likely …

Network analysis: a systems framework to address grand challenges in plant pathology

Plant pathology must address a number of challenges, most of which are characterized by complexity. Network analysis offers useful tools for addressing complex systems and an opportunity for synthesis within plant pathology and between it and …

Multiple origins of downy mildews and mitonuclear discordance within the paraphyletic genus Phytophthora

Phylogenetic relationships between thirteen species of downy mildew and 103 species of *Phytophthora* (plant-pathogenic oomycetes) were investigated with two nuclear and four mitochondrial loci, using several likelihood-based approaches. Three …

A framework for optimizing phytosanitary thresholds in seed systems

Seedborne pathogens and pests limit production in many agricultural systems. Quarantine programs help reduce the introduction of exotic pathogens into a country, but few regulations directly apply to reducing the re-introduction and spread of …

Temperature and light effects on germination of Peronospora effusa sporangia

Spinach downy mildew, caused by the biotrophic oomycete *Peronospora effusa*, is an economically important disease that is found in all spinach growing regions of the US. To effectively predict disease risk we need to understand the response of *P. …