The main tasks pursued by the protection of plants are as follows:
Basic methods:
Looking ahead, we say that in real life, a combination of all these methods is used, which is an integrated method of plant protection. The choice of ingredients depends on the capabilities of the enterprise and the type of crops grown.
This method of plant protection includes the following measures:
In the process of collecting and storing, seeds should be cleared from weed seeds and pests that develop inside it (pea weevil, alfalfa and clover toons). Also, grains should be cleaned from smut sacs, ergot horns, stone barley smut.
Need to monitor the proper storage and use of manure. Concentrated feed before feeding should be ground or steamed. Weeds should be mowed in places of uncontrolled growth before and during flowering. Usually it is the curb, the edges of fields, forest edges.
It is necessary to adhere to the optimal timing and norms of sowing seeds. Crop need to be cleaned in a timely and efficient manner.
The main task of this method is the creation of the most favorable growth conditions for cultivated plants and the suppression of weed growth. Timely harvesting and destruction of crop residues prevents the reproduction of pests and parasites.
All types of soil treatment lead to the destruction of weeds, their seeds and vegetative reproductive organs remaining in the soil.
The method of provocation and strangulation consists of two stages. At the first stage, the peeling of stubble is done by disc or flat-cutting tools to the depth of the rhizomes of perennial weeds. Damage triggers germination of the kidneys. When shoots become visible above the ground, deep plowing is carried out. Weeds deplete the supply of useful substances and can no longer get to the surface, after which they die.
For cleaning the field fallow used cultivation and harrowing. Prickling, before and post-harvest harrowing of tilled crops also allows to destroy a large number of weeds. Already during the growth of the crop, the harrows and cultivators allow you to comb and destroy weeds in rows.
The timely use of micro- and macrofertilizers increases the resistance of cultivated plants to diseases and accelerates growth.
Crop rotations are an effective technique that limits the accumulation of pests, pathogens and weeds in crops. This method is effective in relation to those pests that are tied to certain cultures in their development. For example, grain ground beetle, buryak aphid, Colorado potato beetle, sunflower broomrape.
Proper crop alternation in crop rotation and timely harvesting reduces weed growth. By combining preventive and destructive measures, it is possible to maximally clear the field of seeds and vegetative organs of weeds.
The use of resistant to weeds and pests of plant varieties reduces the need for other methods of protection.
Terms and methods of sowing culture
Another option for plant protection is to shift the timing and methods of planting. To prevent pests from causing significant damage, plant as early as possible. Due to this, the seeds sprout long before the appearance of pests and the damage from the latter is minimal. This option is suitable for the protection of cereals from cereal flies and grain sawflies, peas from pea aphids.
Sowing method can also be a good help in the fight against pests. For spring wheat, narrow-row and cross-sowing is preferred, since it creates unfavorable conditions for the development of stem pests of a given crop. Late crops, on the contrary, can be sown a little later, in order to clear the field of weeds with a few more cultivations.
Early harvesting can significantly reduce the number of pests, because it deprives them of the ability to properly complete the growing season. Early harvesting of potatoes significantly reduces the infection of tubers with late blight and other diseases.
As the name implies, this method involves the use of various traps and other mechanical obstacles to pests. For example, these are mousetraps or glue rings on plant trunks. Or even manual assembly and destruction of insects.
This includes various options for exposure on the harmful organisms or plants by radial energy, ultrasound, electromagnetic fields, heating or freezing. For example, to destroy the dusty wheat sage and barley, their seeds are immersed in hot water (48-50°). On the contrary, for the destruction of pea and bean kernels should be influenced by low temperatures (up to -11°).
In nature, many organisms, somehow parasitic on others. This group of methods involves the search for natural enemies of plant pests. Birds and predatory wasps are used to combat the caterpillars. Trichogram is used to control fruit moths. An interesting direction is growing on empty fields of plants that are food for local entomophages. That is, the preservation of the natural range of entomophages, next to which the crop is sown.
Bacteria can be used to control insects. Once in the insect's body, the spore bacterium germinates and causes the death of the infected carrier.
Biological methods today have several directions:
This is the use of various plant protection products to inhibit the growth and development of various plants. None of the preparations today provides a 100% guarantee of weed control and should be used in conjunction with other methods. In addition, each fertilize application must be justified in order to avoid environmental pollution. Even when spraying herbicides in minimal doses in a certain area, moving with the water in the soil, they can create toxic concentrations in water bodies, get into the organisms of rodents and predators that feed on these rodents.
A harmonious combination of all of the above and gives as a result an integrated method. Its use is possible only with regular observation of the field, monitoring of all parameters. It is important to understand that the ultimate goal of field processing is not to destroy 100% of malicious objects, but to adjust the ratio of useful and harmful. The criterion for this is the so-called threshold of harmfulness, at which harm to harvest exceed the cost of their prevention. Measured in the number of harmful organisms per square meter. In the case that the cost of all types of treatments will be cheaper than the yield loss without these treatments, they can be considered rational.
