Greenhouse and indoor grown cannabis using hydroponics or soil-less growth media, such as rockwool or coir, should be especially vigilant for plant pathogens such as Pythium, better known as root rot. This pathogen thrives in wet conditions and can easily spread through the water system. Early detection and proper management, though, should help prevent Pythium from taking over and destroying your harvest.
What is Pythium?: Disease Symptoms & Signs
Pythium is a soil-borne fungus-like pathogen that often attacks the root system of vulnerable young plants, slowing destroying them as they absorb nutrients. The roots begin to turn brown as they die. Crown rot also occurs, wilting the plant and leaving other symptoms of stunted growth, and leaf yellowing. These symptoms are similar to diseases caused by other plant pathogens, however, and therefore a QPCR based molecular genetic test would be the most accurate method to determine if Pythium is present.
How To Prevent/Manage Pythium
- Do not let water stand or overwater your growth media.
- Know the water retention capacity and porosity of the growth media for proper aeration and drainage.
- Disinfect all greenhouse equipment and potting material.
- Periodically test your water system.
- Control pests that serve as vectors for many plant pathogens.
With proper management and regular testing, Pythium can be prevented from infecting your site and causing entire crop losses.