Diagnosis, treatment, prevention and control
From Allotments4All
Plant health care - An overview
Diagnosis, treatment, prevention and control.
Diagnosis can be defined as the identification of the specific pest or disease. Inspecting the plant and the area surrounding it will reveal signs and symptoms.
It is essential that the host plant be correctly identified first, as this enables pest and disease identification to be more accurately made. It is impossible to effectively treat or control a pest or disease without first undertaking a diagnosis of the problem.
The signs of a problem will be physical manifestations of the pest or disease, such as caterpillars on a cabbage leaf. It is only possible to see these signs when the pest or disease is visible to the naked eye, so viruses and bacteria do not show signs, only symptoms.
The symptoms will be the effect on the host plant, such as the destruction of the cabbage leaf by the caterpillar, or the brownish-black, foul smelling lesions caused by Bacterial Soft Rot – Erwinia carotovera on Allium spp.
Prevention can be defined as avoiding the pest or disease by anticipating it and taking action. Planting resistant cultivars is a form of prevention. By preventing the problem in the first place, costly treatments can become unnecessary.
Treatment can be defined as the action taken against the pest or disease to help restore the plant to full health or prevent the pest or disease from establishing itself.
For plant disorders, such as nutritional deficiencies, applying the correct type of feed will be an effective treatment, or where a plant is wilting due to lack of water, irrigation.
Treatments can be preventative, such as in the application of fungicide when watering seedlings, to help prevent damping-off caused by Pythium spp. of fungus.
Treatments and controls must be appropriate and timely to be effective.
Control can be defined as taking action to limit the effect of the pest or disease, and can take several forms.
Physical and cultural controls include using barrier methods such as ‘Enviromesh’ to prevent insect pests reaching plants and regular weeding to remove plant hosts.
Pesticides include biological methods in which particular predators are introduced expressly to attack pests, and chemical applications such as spraying infested plants with approved products.
Legislation controls the spread of certain pests and diseases by restricting the movement of host plants and requiring producers to operate quality control measures.
Integrated pest management uses a blend of methods in a complementary manner to control pests and diseases, with the aim of doing so effectively, without wasting resources and with minimal impact upon the environment.
