The hot and rainy weather has brought out the annual anthracnose disease for mirlitons. See the last summer’s blog entry here on this disease (I have added a photograph and link to more photos) which discusses how to recognize the different signs of powdery mildew and anthracnose. The growers guide on the web site has additional information. Anthracnose infects almost all mirliton plants, especially in their first year, but depending on proper care and hopefully a low rate of evening rain showers, the disease will only affect a few stems and when those die, new stems will return.
Mirliton leaf infected with anthracnose plant disease. Note different browning pattern and the distinctive “shot hole” in the middle of the brown tissue, which does not occur with powdery mildew (anthracnose, unlike powdery mildew, can live on dead plant tissue and literally “eat a hole” through the plant)