By Guido Schnabel and Madeline Dowling, Clemson University

Anthracnose fruit rot, caused by Colletotrichum fungi, is an explosive disease of strawberries and other small fruits that is capable of wiping out an entire crop. The usual gray mold control program can help control anthracnose disease, but when that fails, anthracnose spreads like wildfire and it is game over for the strawberries. The disease is very tough to control with fungicides when established. Many fungicides are not effective enough to hold anthracnose back, and resistance issues have made the use of previously effective fungicides more of a gamble. To complicate the matter, there are different types (species) of Colletotrichum that can differ in sensitivity to fungicides. In our opinion, we must start looking at additional means to reduce this disease. In a new article published in the journal Phytopathology, Dr. Gerald Holmes at the Cal Poly Strawberry Center in California stresses the importance of using new strawberry cultivars with resistance to soilborne diseases as an additional tool to manage Macrophomina, Fusarium, Phytophthora, and Verticillium diseases. The availability of these cultivars is a result of breeding programs across the country expanding their mission to also include disease tolerance as an important trait in their new breeding lines. Scientists in Florida have identified genetic markers for anthracnose fruit rot resistance, and we are hopeful that the efforts of this and other breeding programs will provide the tools we need for improved anthracnose management. Some of these new cultivars are commercially already available. For example, ‘Florida Radiance’ and ‘Florida Brilliance’ are moderately resistant to anthracnose and ‘Sensation’ is highly resistant. It is unknown, however, how these specific cultivars bred for use in Florida will perform in other states with different environmental conditions. It may be worth your while to test a few rows of these and other promising cultivars on your farm.

Image Credit: Madeline Dowling,
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