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Discovering a crop has a root disease or a virus infection is a horrible moment for any grower. Some will use a chemical to try to control it, but this approach is often not effective and may even worsen the situation. As with everything, prevention is better than cure. Prevention starts with understanding what causes root or virus diseases * and what steps can be implemented to avert difficulties in advance.
The start of a disease is when a pathogen, like a fungal spore, is released from a source and transmitted by a 'vector' into a crop. A vector is something that helps the spread of a pathogen. For instance, it is not unusual for the irrigation water to be contaminated with fungal spores. Through irrigation, spores are introduced into the growing system. If a fungal spore lands on a plant root, the spore germinates and produces 'mycelium' thread that penetrates the plant root. If the fungus grows inside the plant and establishes itself, the plant is infected. Millions of spores will be produced and released. The infected plant is host to the fungus, and it also becomes a source of fungal spores.
Then a vector, such as water, wind, insects or people spread the spores to other plants. There the spore germinates and infects the plant. Millions of spores spread from here. After some time all the plants are infected and the system is full of spores and fungal growth. Obviously the production will suffer.
There are ways to break this circle, namely by controlling the sources of the pathogen and/or the vectors.
Rapid spread to all plants
Water is a notorious vector for pathogens such as fungal spores, bacteria, viruses and nematodes. If the raw water or the nutrient solution contains pathogens, the disease will spread rapidly to all plants. If the drain water is re-used for irrigation, the disease will spread even faster. Recirculation is a good thing, because it saves water and fertilizers and avoids the emission of nutrients to the environment. But there is a serious risk of spreading diseases. Filtration is not a solution, because fungal spores, bacteria and viruses are too small to be caught by a simple filter. Proper disinfection is the only option.
The start of a disease is when a pathogen, like a fungal spore, is released from a source and transmitted by a 'vector' into a crop. A vector is something that helps the spread of a pathogen. For instance, it is not unusual for the irrigation water to be contaminated with fungal spores. Through irrigation, spores are introduced into the growing system. If a fungal spore lands on a plant root, the spore germinates and produces 'mycelium' thread that penetrates the plant root. If the fungus grows inside the plant and establishes itself, the plant is infected. Millions of spores will be produced and released. The infected plant is host to the fungus, and it also becomes a source of fungal spores.
Then a vector, such as water, wind, insects or people spread the spores to other plants. There the spore germinates and infects the plant. Millions of spores spread from here. After some time all the plants are infected and the system is full of spores and fungal growth. Obviously the production will suffer.
There are ways to break this circle, namely by controlling the sources of the pathogen and/or the vectors.
Rapid spread to all plants
Water is a notorious vector for pathogens such as fungal spores, bacteria, viruses and nematodes. If the raw water or the nutrient solution contains pathogens, the disease will spread rapidly to all plants. If the drain water is re-used for irrigation, the disease will spread even faster. Recirculation is a good thing, because it saves water and fertilizers and avoids the emission of nutrients to the environment. But there is a serious risk of spreading diseases. Filtration is not a solution, because fungal spores, bacteria and viruses are too small to be caught by a simple filter. Proper disinfection is the only option.