By Andi Anderson
Xanthomonas is a serious bacterial disease in begonias, and once plants are infected, greenhouse growers must take careful action to protect the rest of the crop. In this final part of a Michigan State University Extension series, experts explain how to dispose of infected plants properly and reduce future losses.
Once a positive diagnosis is confirmed, fast action is critical. There is no cure for begonias infected with Xanthomonas. All plants showing symptoms should be removed immediately.
Growers must also remove plants located within splash distance of infected ones. Because there is a delay between infection and visible symptoms, nearby plants should be treated as infected even if they appear healthy.
Careful scouting helps determine how much plant material must be removed. When infection levels are low, removing individual plants may be effective.
However, when symptoms are widespread, destroying entire sections of the crop may be the safest choice. Mapping where symptoms appear can help growers understand how far the disease may have spread.
Proper disposal practices reduce the risk of spreading bacteria. Infected plants should be discarded when foliage is dry. Workers should wear disposable gloves and coats or washable aprons.
Diseased plants should never be composted, and containers used for infected plants should not be reused. These steps help prevent bacteria from surviving and spreading.
Documenting losses is also important, especially for insurance or reporting purposes. Growers should keep a diagnostic report confirming the disease. Photos of symptoms and plant counts should be saved.
Recording a video walk through the greenhouse with a visible timestamp can provide strong documentation.
After plant removal, thorough sanitation is essential. All plant debris must be cleared from benches, trays, aisles, and floors. Surfaces should be cleaned first to remove soil and organic matter, then sanitized using approved disinfectants such as quaternary ammonia products. Porous materials like weed mats are difficult to disinfect and should be replaced.
Following strict disposal and sanitation procedures helps stop disease outbreaks and protects future crops. While removing plants is a difficult decision, these steps can prevent greater losses and support long term greenhouse success.
Photo Credit: michigan-state-university-msu-extension
Categories: Michigan, General