Disease Management

The course was developed by Informa/Farm Progress and will provide an overview of the top disease and pest threats to citrus orchards in California, Florida, and Texas.

In 1996, California voters approved the use of cannabis for medical use, with the requirement that patients must have a licensed physician’s recommendation. Then in November 2016, California voters approved Proposition 64, allowing adult use of cannabis under some specific use and quantity conditions. In June 2017, the California legislature passed the Medicinal and Adult-Use Cannabis Regulation and Safety Act (MAUCRSA) which Governor Jerry Brown signed into law. Each of these legal actions provided information on specific legal restrictions and requirements. MAUCRSA created one regulatory system for both medicinal and recreational use of cannabis.

California almonds are susceptible to many diseases, which can reduce crop yield and quality in both current and subsequent years. They also can weaken and, occasionally, kill trees. Almond diseases are caused by a wide variety of microorganisms including fungi, bacteria, and viruses. They also can result from certain environmental stresses or genetic disorders. Some occur only at particular times of the year; others remain in the tree and exhibit yearlong symptoms. Disease infections may be more or less severe depending on age of the tree, variety, and environmental conditions such as rainfall, temperature, humidity, soil type, and soil moisture content. In order to fully understand the impact of disease organisms and environmental conditions on almond trees, it's important to understand the tree's seasonal cycle, growth processes, and crop development. The purpose of this course is to provide an update on current diseases that occur in California almonds--everything from branch and root diseases to vascular disorders--and the latest disease management practices that can protect valuable orchards and crops.

Potassium nitrate is used in agriculture, industry, solar energy plants, food and pharma. In agriculture, the main uses of potassium nitrate are related to the supply of plant nutrients via fertigation, foliar and field applications. Potassium nitrate has also proven to be a valuable tool in crop pest and stress management and has shown positive effects on the control of plant pests and diseases when applied or as an additive to crop protection agrochemicals, thus allowing the grower to practice more effective and judicious use of pesticides. When used correctly, potassium nitrate can be a valuable and economic source in any Integrated Pest Management (IPM) strategy, not only for its effective and environmentally sensitive aspects, but for its effects on overall plant health, thus creating a stronger, more resistant plant. This is demonstrated in this course by a number of examples of pest management with potassium and nitrate sources. This course also has a section on the role of nutrients in IPM and is sponsored by SQM.

Grape Powdery Mildew is the number one disease in California vineyards. More dollars are spent on powdery mildew control and, yet, this disease still accounts for more crop losses than any other grape pest. This course, sponsored by Western Farm Press, explores the different fungicide classes; treatment options for powdery mildew in California; resistance management, and regional differences in disease development. It also includes a detailed approach to using the UC Powdery Mildew Risk Assessment Index (RAI) to predict infections. Seasonal patterns of disease development differ from region to region (as well as year to year), and cost-effective management strategies must be based on local conditions that favor or inhibit pathogen reproduction. Season-long control depends on reducing early-season inoculum and subsequent infections with well-timed fungicide applications. Spray timing and frequency (and coverage) is everything; these vary depending on local weather, temperature, varietal susceptibility, vine growth stage and material choice.