Potato pests and diseases are the first thing that leads to the decrease in your yield, along with this, its quality is reduced, so there can be storage losses. With untimely and poor-quality protection of potatoes, the yield of tubers is reduced by 28-50% or more. Losses of potatoes during storage as a result of the development of wet and dry rot and other diseases often reach 30-40%.
The new pest and disease control strategy is based on the integrated plant protection system, which is based on the fact that, along with chemical and biological methods for the destruction of potato parasites, a whole range of agrotechnical and technological measures is used, which also includes new potato varieties.
About 50 harmful insects and more than 80 potato diseases have been registered on potatoes.
Potato pests
Wireworms and fake wireworms make wormholes in tubers. When the number of these pests in the soil is 5-6 ind./m2, 80% of tubers are damaged.
May beetle larvae make round or elongated holes in the tubers. They eat away the pulp along with the peel, which distinguishes the nature of their harm from scoop damage. May beetle larvae damage potatoes, starting from the second year of life.
Mole crickets mainly damages tubers, also eating out the pulp of the potato along with the peel, while a small tuber can be eaten whole. With a significant number of this pest, crop losses can reach 30%.
The most dangerous pests on potatoes are:
- Colorado beetle;
- potato moth;
- wireworms, fake wireworms;
- larvae of lamellar beetles;
- caterpillars of cut worms;
- mole crickets and others.
Cut worms, or rather their caterpillars, infect potato stalks a little deeper than the soil level. The larvae gnaw out the pulp without damaging the peel, unlike beetle larvae.
Potatoes are also affected by sucking insects, the first thing they damage is the leaves. Red spiders damage is characterized by the appearance of yellowish or rusty small spots and stripes along the veins. The place of sucking is browner, dries up, and the withered lobe hangs down.
When potatoes grow closer to the end of the growing season (second half of June - early July), potatoes are damaged by potato and pith owlet moths. Caterpillars of owlet moths bite into the lower part of the stem, making a move inside to the top. The stems then wither and break off.
Potato diseases
Recently, the harmfulness of many widespread diseases has increased on potatoes:
- late blight;
- Alternaria blight;
- common scab;
- dry and wet rot;
- blackleg;
- stem nematode, etc.
Late blight, unfortunately, is still the most harmful disease. Factors that affect the level of damage are weather conditions, the timing of the onset of the disease on potatoes, and the general agricultural practices of cultivation. The earlier phytophthora affects potatoes, the more crop you can miss. When late blight develops at the end of the growing season of potatoes, it does not cause a strong reduction in yield, but if there are problems during harvesting, then infection of healthy tubers with diseased ones can cause crop losses. Yield losses from this disease can reach 70%.
Potato Alternaria blight can, like late blight, lead to significant crop losses. Potatoes are usually affected by Alternaria blight before tuberization begins. It spreads in focuses. The tops are mainly affected, and yield losses from this reach 20-25%, in addition, the level of starch decreases by 1.5-3%. Mid-season and late varieties are more susceptible to Alternaria blight.
Rhizoctonia blight causes a significant threat to seed production. The lack of varieties resistant to this disease and effective disinfectants of seed material leads to the fact that brown spots or ulcers appear on waterlogged soils on sprouts, stolons, roots, underground parts of stems.
Recently, there has been an increase in the harmfulness of common scab on potato tubers. The most favorable conditions for the development of the disease are: dry and hot weather, lack of moisture in the soil during the formation of tubers. Depending on the degree of damage to the tubers, the yield decreases, starch content decreases, and the marketable qualities of potatoes also deteriorate.
Potato diseases during storage
During storage, dry and wet rot took the first place in terms of harmfulness. These diseases are widespread. Under normal storage conditions, the losses are, of course, 10-15%. When storing potatoes at high temperature and humidity, they can reach 30 and even 50%.
The main factors that contribute to the affection of tubers and the subsequent spread of diseases in the field are warm weather with frequent showers at the end of the potato-growing season, frequent use of machinery, which leads to soil compaction. High humidity and relatively high temperature during storage leads to infection of tubers in storage.
Recently, the harmfulness of the stem nematode has increased. The disease has become widespread, drastically reducing the quality of seed and food potatoes. With the penetration of nematodes into the tubers, the skin on them becomes discolored, and then becomes lead-gray in color, easily separated from the pulp and cracked. Nematodes are on the edge of the healthy and affected part of the tuber.
The harmfulness of the stem nematode is manifested by the decrease in the seed and commercial qualities of tubers. In addition, it is the root cause of potato decay during storage.
