How To Deal With Late Blight And The Colorado Potato Beetle

2024 Author: Sebastian Paterson | [email protected]. Last modified: 2023-12-16 13:47

Late blight

Often potato growers are perplexed: there was a luxurious tops of the potato and suddenly it was gone in 3-4 days. There are only 90-100 small tubers left under the bush. This did its dirty work late blight - a disease that poses a particular danger, since in the conditions of peasant farms and horticultural plots it is not always possible to ensure compliance with crop rotation.

The timing of the appearance and the massive spread of late blight largely depends on weather conditions. If, during the flowering period for 8-10 days, the air temperature fluctuates between 15-20? C, the relative humidity is at the level of 75-80%, which is created by the fall of 15-20 mm of precipitation, abundant night fog and dew, then late blight will appear quickly, and plants can die in 3-4 days.

The disease develops latently throughout the growing season. However, due to the high resistance of the potato, in the first stages of growth and development, only the accumulation of infection occurs. The first signs of late blight are small brown spots on the leaves and a white bloom of mycelium along the edges of the spot on the underside of the leaf. The mycelium is clearly visible in the morning when the dew has not melted.

Gardener's guide

Plant nurseries Stores of goods for summer cottages Landscape design studios

Potato growers need to apply technological, preventive and exterminatory control measures against late blight. The effectiveness of measures to combat late blight is presented in the table.

These tables show that with the help of various measures it is possible, if not to get rid of, then to minimize the loss of potatoes during the period of maximum phytophthora load on plants.

Here's one example. What conditions are created by potato growers who annually apply unripe manure? Together with him, they carry billions of weeds, which are difficult to control during the closing of the tops, and after the tops of the potatoes lie down, they dominate the main crop. In these thickets, ideal conditions are created for the development of phytophthora.

The mistake of many potato growers is that they begin to fight against late blight when the disease has already manifested itself, and, moreover, they use drugs, for example, Bordeaux liquid, which must be used for preventive purposes. Naturally, such treatment does nothing, and the disease progresses.

Notice board

Kittens for sale Puppies for sale Horses for sale

Bordeaux liquid - an effective preparation for preventive treatment - is prepared on the day of use: 60 g of quicklime is dissolved in a three-liter jar of cold water, and 60 g of copper sulfate is dissolved in another, with hot water. Before spraying, the solutions are mixed and poured into the sprayer. Plants are cultivated on the lower and upper side of the leaves. 6 liters of funds are spent per hundred square meters.

Now the processing of potatoes with environmentally friendly extracts of various plants has become widespread. For this, onions are used, roots of radish, radish, poplar leaves, bird cherry, heads of garlic. To obtain the required solution, take 10 g of components per 1 liter of water. A hundred square meters of potato plantings require 6 liters of water.

Of the chemicals used for prophylactic spraying: cuprozan, zineb, copper oxychloride, polycarbocin and others.

If, nevertheless, the first signs of late blight appeared on the underside of potato leaves, then it is imperative to carry out destructive spraying of the plantings. To do this, you can use a solution of ridomil: 30 g of the drug per 10 liters of water. If you don't have scales, it doesn't matter, a matchbox is what you need. A very effective mixture of drugs, consisting of 1 part of ridomil and 8 parts of polycarbocin. The concentration of the drugs is the same.

Now a large number of drugs are being sold, the packaging of which always contains instructions for their use.

Carrying out the treatment before the rain is ineffective, and if it does rain, then the treatment should be repeated. For better retention of the preparations on the leaves, 1-2 glasses of soap solution should be added to the solution before spraying. Spraying is repeated after 14-16 days.

Potato varieties resistant to late blight

Potato varieties take a special place in preventing the development of late blight. The peculiarities of different varieties of potatoes make it possible to distinguish a significant group of varieties resistant to late blight. Here are some of them.

Zarya is an early variety for dining purposes. Resistant to late blight, cancer, viral diseases and bacteriosis. The variety is distinguished by a high content of vitamin C in tubers in July - August, therefore it is very useful for children. The harvest reaches 1400 kg per one hundred square meters.

Early-fruiting - early variety, small eyes. Preparing tubers for planting - germination, while the harvest can be obtained in June. Resistant to cancer, late blight, viruses, bacteriosis. The harvest can reach 1500 kg per one hundred square meters.

Luck is a very early variety for table use. Differs in large tubers. Resistant to diseases, especially late blight and viruses. In terms of economic benefits, it is 1.5-2 times higher than many varieties and local material. It tolerates cold snaps well, is less affected by the Colorado potato beetle. Drought-resistant. Harvest up to 1500 kg per one hundred square meters. Stores well.

Reserve - medium early variety, small eyes. Resistant to cancer, bacterial diseases, late blight and viruses. Resistant to drought and waterlogging. Loose tubers. Harvest up to 1500 kg per one hundred square meters.

Nevsky is a medium early variety. None of the varieties have such beautiful tubers as this variety. Potato growers love it for its minor waste from cooking and for its taste. Resistant to drought and waterlogging. Harvest up to 1300 kg per one hundred square meters. The storage is excellent.

Blueness is a mid-season variety. Differs in resistance to late blight. It tolerates cold weather, the most delicious in the country, friable tubers. Harvest up to 1600 kg per one hundred square meters.

Lugovskoy is a mid-season variety. The tubers are crumbly, when boiled they look like blossoming rose petals. Resistant to late blight. Responsive to deep loosening. The harvest is high - up to 1500 kg per one hundred square meters. Excellent storage.

Timo is a very early variety, gives high yields everywhere, ripens before the appearance of phytophthora. Drought and disease resistant, high starchy. Harvest up to 1600 kg per one hundred square meters.

Nida is a mid-season variety, resistant to nematodes and phytophthora, does not suffer from waterlogging and drought, gives high yields up to 1500 kg per hundred square meters in any soil and climatic conditions.

Colorado beetle

In farms, peasant farms, in personal and garden plots, considerable damage is caused by another pest - the Colorado potato beetle, which has spread throughout Russia. He eats the leaves of plants, often leaving only petioles from them.

The larvae feed on leaves for three weeks, then go into the soil to a depth of 5-8 cm. After 6-15 days, the pupae turn into beetles and come to the surface. Depending on climatic conditions, up to three generations of the pest can develop over the summer.

Adults hibernate in the soil and leave it when the soil warms up to 12-16 ° C. This temperature often occurs before the emergence of potatoes. The Colorado potato beetle is awaiting the appearance of its plants at this time. Eagerly pounces on juicy, tender sprouts. Colorado beetles can be destroyed with chemicals. Most often they use benophosphate, dibrom, dilor, foxim, respectively 60-140, 10-20, 100-150 g per 10 liters of water.

Liquid consumption when spraying is 6-8 liters per hundred square meters. For the destruction of the Colorado potato beetle, drugs Ankara, Regent, Karate are also used with a consumption rate of 4-5 liters of working fluid per one hundred square meters. Fostak and decis preparations are characterized by high efficiency in potato planting. In order not to oversaturate the soil and tubers with chemicals, environmental protection methods can be used. After the end of the harvest, they dig up the soil to a depth of 20-22 cm, arrange traps from peeling potatoes with the subsequent destruction of the beetles that have climbed there.

Due to the absence of the Colorado potato beetle, a carrier of phytophthora, on the plantings, plants suffer less from this disease, and on varieties resistant to phytophthora - Udacha, Golubizna, Nevsky, Timo - it did not exist at all.

Recently, due to the multiplication of disease-resistant, highly productive varieties, the manifestation of late blight has weakened. And if potato growers grow more new, resistant varieties of potatoes, their colonization of plantings can be minimized. For use on individual and summer cottages, tubers of the following varieties can be offered in autumn and spring: early - Udacha, Nevsky, Timo, Lukyanovsky, Zhukovsky early, Moskvoretsky, Zarya, Reserve; mid-ripening - Lugovskoy, Golubizna, Rodnik, Vestnik and others, as well as the seeds of a highly productive combination variety Udacha-variety Golubizna.