Safer, less expensive biological control may be right under our feeT BY VERONICA ANCONA, Associate Professor Citrus Center, Texas A&M University Kingsville
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merging diseases and pathogens continue to be the main cause of yield reduction in agriculture worldwide. Unfortunately, this is also the case for citrus growers in South Texas, especially in the Lower Rio Grande Valley where incidence of Phytophthora foot rot disease is widely spread. The disease, caused by the soil-borne pathogen Phytophthora nicotianae, reduces tree vigor, fruit yield and can even cause tree death over time. Depending on the severity of the infection, affected trees produce less and smaller fruit, reducing tree productivity and overall yield. To combat Phytophthora infections, fungicides are used as controlling agents. Effective chemical products reduce P. nicotianae levels in the soil, resulting in root recovery and increased fruit size. But effective chemical products can be expensive and require reapplication each growing season.
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Percent yield loss per grapefruit tree depending on Phytophthora foot rot disease severity rating Excessive use of fungicides can also increase the likelihood of pathogen resistance buildup after being preexposed to these chemicals. To avoid pathogen resistance
