In today’s Almond Matters, brought to you by Valent, areas of California received some rainfall this week, highlighting the importance of good disease prevention. Field Development Manager for Valent USA, Pat Clay said that after the rainfall event preventative sprays are going to be essential. The most effective approach for fungicide treatments is getting out in front of infection.
“Fungicides are going to give the best results when you go out when conditions are favorable for disease development, which obviously we’re in that right now. So, getting the application on before the disease gets ramped up is critical,” said Clay. “Even when we don’t get rainfall you still need to be on the watch out for disease. But when you have showers like this and a lot of free moisture in the canopy, diseases do become top of mind.”
A solid fungicide program in April can help keep issues of Alternaria, rust, and scab to a minimum. Once defoliating diseases get out of control the trees can begin losing their leaves, putting negative pressure on nut development and impacting yield. Clay noted that ultimately, “keeping healthy, functional leaves on the tree is the goal of a good fungicide management program.”
The added moisture in the orchards, followed up by warming and mild temperatures creates an ideal environment for disease development. Orchards can still be an ideal microclimate for disease even without rain events, with irrigation systems providing moisture for pathogens to grow in warm weather. Clay explained that another important consideration for disease prevention is material selection. Rotating chemistries in orchards is critical for helping to delay or prevent the development of resistance.
“Quash fungicide is a very effective fungicide against the major almond diseases that we have here in California,” Clay explained. “April applications, May applications, June applications with Quash fit very well when rotating with other fungicides with different modes of action.”
Listen to the report below.