Disease problems in in flowering plants
One of the biggest challenges for any gardener, from the first time gardener to the most experienced, is preventing outbreaks of disease. Flowering plants are prone to a variety of pathogens, including bacterial infections, fungal infections and viral infections. The difference between fungi, virii and bacteria is that only fungi can survive outside of their plant host in the soil. Bacteria and viruses need the presence of a plant host in order to survive.
Fungi are able to reproduce through the use of small spores. These spores can be thought of as the fungi equivalent of seeds. Spores are produced in large numbers, and as they travel some of the spores enter the plants through the root system. Other spores can attach themselves to the leaves, stems, flowers and other parts of the plant. Once single infected plant is able to release up to 100 million individual spores, so it is easy to see how quickly a fungal infection can spread throughout a garden.
Unlike fungi, which can remain dormant and survive in the soil, bacteria need both warmth and water in order to grow. Therefore, the diseases caused by bacteria tend to be more prevalent in warm and humid conditions. Bacterial infections are easy spread through rain, splashing water and inadvertently by gardeners as they move between the plants. Bacteria usually enter the plants through either an open wound or a natural opening.
The other common plant infectors are viruses. Unlike bacteria and fungi, viruses can only multiply within the cells of the host plant. Some viruses are transmitted by insects such as leafhoppers, thrips and aphids. Others are carried through infected pollen and seeds. Like bacteria, viruses commonly enter the plant through a cut or open wound.
When it comes to treating plant diseases, gardeners should strive for the most natural solution properly, moving to chemicals only after natural solutions have failed. This is particularly important if the flowers are to be sold to the public. Good public relations generally requires keeping chemical use to a minimum, and excessive chemical use can be damaging to the soil as well.
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