How to deal with leaf spots?
The causes of leaf stains and deformities vary and are often harmless. Sometimes, however, a quick response is needed.
There are situations, when one or more of the plants we grow suffer from causes that are difficult to identify. This is happening, when various kinds of spots and distortions appear on the leaves. In this case, the plant may suffer from one or more of the leaf spot diseases. Something could have happened in her environment as well, which directly affected the leaves, and the disease, having easier access through damaged tissue, is the corollary of this. We must remove the cause of these phenomena, because the problem will only get worse.
Strange patterns on the leaves are sometimes a natural feature, The change in their appearance is also sometimes related to the season. In late summer and fall, leaf shedding plants undergo hormonal changes, preceding leaf fall. They may also be accompanied by a color change. Thus, the true leaf spot is the result of fungal infections. On the other hand, other distortions and marks on the leaves are caused by external factors. In this case, use a fungicide, without forgetting to remove any root cause of the disease.
Stains not caused by fungi.
Fungi infections are often very vague. Therefore, if there are spots on more than one plant, the reasons for their formation can be quite simple. Sometimes these are drops of hot water, paint or oil. It can be a plant fertilizer in granules, which collects in the hollows of the plant and is not absorbed. Another possible explanation is use (such as Bordeaux liquid, which is a reaction product of copper sulphate with lime milk) harmful to the plant, or the use of inappropriate ones, or poorly mixed pesticides.
The true leaf spot is difficult to identify. How can we know, that it really is spotty, not just a stain, or which stains should worry us, and which we can ignore. The spots that appear are usually small and have a rounded shape. You should watch them closely, as they can spread quickly, gradually becoming a serious problem, But let's remember, that some stains on ornamental plants should not worry us, if they don't change their appearance too much. According to the accepted principle, edible plants should be treated, because they get their nutrients through the leaves. If this road gets damaged, the productivity of the plant decreases. Because there are many types of fungi at stake, not to mention bacteria and viruses, which also cause stains, measures with a broad spectrum of action should be used, and not targeting specific fungi. Generally speaking, it is wiser to adopt a prevention strategy through a controlled program of fungicidal treatments, than wait for problems to arise. But, as with all rules, there are exceptions. Clam leaf blotch causes red spots on the foliage. Coupled with excessive watering, this fungus can have a detrimental effect on infested leaves. Unfortunately, does not respond to commonly used fungicides.
Application of fungicides
At the first symptoms of an attack, we clean the plant from dead parts and. we spray with a standardized fungicide. If this problem occurs on crops, the fungicide active ingredient must be suitable for the plant in question. In the case of edible plants, we always follow the manufacturer's recommendations, concerning breaks in harvest after its use. Some agents are applied differently to different plants. We check it in the attached instructions.
Choosing a chemical control method, we have to remember, that some plants are allergic to chemicals, and, that disease-causing organisms can become resistant, if we use one fungicide too often. We choose the product carefully, we read the manual and do not use the same measure over and over again.. However, before we use another as a replacement, we have to make sure, that it does not contain the same active substance, what the previous one. Also, let's not make assumptions, that the natural substance will be harmless to the plant.
Mode of action
Most of the fungicides are systemic. They are absorbed by the plant's body and thus protect it against recurrence of infection. We always look for the active substance on the fungicide packages . Manufacturers often change the names of their products, so it is important, to look for names common to all control measures, that is, the active substance. Here are the most common active substances:
– Benomyl, that is, a powdered systemic fungicide, with a moisturizer called Activex 2, Do not use on apples and strawberries.
– Carbendazim is a systemic fungicide m. We use it on most potted plants and food crops.
– Oyster. to fungicyd systemiczny, similar to benomyl.
– Kaptan is a preventive fungicide, produced on the basis of sulfur. It should not be used with apples and soft fruits, from which we will make preserves or freeze, because it can spoil them.
– Thiram is another preventative fungicide. It is added to the hormone rooting in the form of a powder, to protect the seedling during the period, when it is weakest. Thiram should be used with caution, as it can be irritating, and do not use it with fruit, which are intended for preserves or for freezing, We wait two weeks after using it, before harvesting the edible plants.
– TCNB or Teknacen is the only product currently available in the form of fumigating candles, usually in combination with an insecticide. TCNB dries the air and is useful in confined environments, type of greenhouse or orangery. After using it, you should wait two days before collecting edible plants.
DISTRIBUTION OF FUNGAL INFECTION
Many fungal diseases are transmitted through microscopic airborne spores. They can develop on soil or dead plant tissues. So keep your farm clean and well ventilated. The air must be fresh, we avoid heat and stuffiness. Some pathogenic fungi, e.g.. Heteropatella an tirrhini, they spread through contaminated seeds,