potato Diseases

August 12, 2017 17:52 | Vegetable Plants

blight.On the lower leaves of the bush appear grayish or dark brown spots.On the underside of infected leaves, a white furry coating, which is sporulation of the fungus.On stems and petioles disease manifests as brown bands.In the tubers are formed slightly depressed, sharply outlined brown stains that penetrate into the flesh as a light-brown streaks or bands.

Control measures. Cleaning and destruction of infected plant residues, timely and deep hilling by closing before the foliage, removal and destruction of diseased foliage before harvest (7-10 days), drying the tubers before setting them in storage.In the period from the bud before flowering potato plants is carried out first spraying one of the following drugs: 1% solution of Bordeaux mixture (100 g of copper sulfate and 100 g of lime per 10 liters of water), homom (40 g per 10 liters of water).Working fluid consumption - 6.8 liters per 100 m2.

Early dry spot.It affects the leaves and stems.On the leaves are formed rounded-angular, with concentr

ic circles macrosporiosis spots.After 12-14 days the leaves spots appear without the blight of concentric rings.The disease develops rapidly, the spots coalesce, crumble.The leaves are fringed, wither.On stems and petioles elongated spots.Startled tops dry out well before the end of the growing season.

Cancer affects potato tubers and stolons.For tuber growths formed various shapes and sizes.In dry hot weather, the disease manifests itself in the form of warts, similar to common scab.

Control measures. Infected tubers can not be used in any food or fodder.Cancer growths disinfected with bleach, kerosene, and buried to a depth of at least 1 m.

Rhizoctonia (black scurf) affects the tubers, shoots, stems, and stolons.In the tubers are formed black sclerotia solid adhering to the peel, sometimes thin black mesh extending over the entire surface or part of the tuber.Infected shoots are covered by dark brown spots and sores nadlamyvayutsya defeat in the places and die.On stolons disease manifests itself in the form of brown spots and streaks.At the root of the stems in wet weather there is a white felt coating.The defeat is accompanied by a weak twisting of the upper leaves, the appearance on their purple color, form aerial tubers.

Control measures. Planting healthy tubers in optimal time;Use rotted manure or compost;Timely weeding and tillage;harvest until sclerotia on tubers.

Fusarium (dry rot) develops in tubers during storage of potatoes.In the tubers are formed grayish-brown, slightly sunken spots.Then the pulp is under the spot becomes loose, gets a brownish color.It voids filled with a white, yellowish or dark fluffy mycelium of the fungus.The infected tissue quickly dries, peel wrinkled, forming folds around the original spot. Control measures. Observance of storage conditions;prevent mechanical damage to tubers during harvest;fighting during the growing season diseases and pests.

Gangrene Gangrène (Button sewing rot) affects stems and tubers which rot during storage by type of dry rot.On tubers appear sunken dark spots, the skin in the area of ​​crack spots within the affected tissue formed dark brown pycnidia. Control measures. See. Fusarium.

Common scab affects the tubers during the growing season.The disease develops in the form of a flat, deep, and convex shapes mesh.With strong development of scab tubers covered with a solid crust, reduces germination.A deep form of the disease causes the cracks through which penetrate the tubers in other pathogens.Excess lime application, the use of fresh manure, the cultivation of susceptible varieties, hot and dry weather during the growing season contribute to the development of common scab. Control measures. best precursors for potato - Legumes.On acid soils lime is introduced in the autumn of small doses.Use varieties resistant to scab.

Powdery scab affects the tubers, stolons and roots.Initially, the young tubers appear brownish spots, which then increases, the spots formed on the spot warts, which become brown.When drying of the skin on the warts star-bursts and exposes the dark powdery mass of spores.On the roots and stolons formed small zhelvachki - first white, then they darken and decompose.

Control measures. Adding micronutrients;liming acid soils;before planting the tubers sprayed preparation hamster (20 by 8 liters of water).

lumpy scab (osporoz) affects the tubers before the harvest, and the symptoms of the disease appear during storage: about holes formed lumps that do not break, like powdery scab and merge, covering a large part of the surface of the tuber.Development of the disease favors moist and cool weather during the tuber, as well as violation of tubers storage mode. Control measures. Application of organic and mineral fertilizer with trace elements, as well as optimal storage mode when using an active ventilation.

Silver scab affects the tubers - they first appear in the autumn of smooth dark yellow circular spots, and then depressed with a silvery sheen.The development of silver scurf is suspended at a temperature of 1-2 ° C and relative humidity no higher than 90%.

Control measures. crop rotation;early removal of tops and harvesting of tubers for seed;adherence tuber storage.

Anthracnose (partroz) affects stems and tubers.Patients with lower tier plant chlorotic leaves, stems angular, truncated.On the stems appear light brown spots.In dry weather, the plants wither, fray in rainy stem tissue osliznyayutsya and rot.On tubers during harvest anthracnose appears as a dark brown blurry spots under the skin formed on the surface stains microsclerotia.During storage at elevated temperature and humidity on the tubers developing wet rot. Control measures. crop rotation;weed control;Deep incorporation into the soil of crop residues after harvesting potatoes;potato planting in optimal time;compliance with the conditions of storage.

Blackleg affects the plant during the growing season and tuber storage.Plants are stunted, the leaves, starting from the top, turn yellow and curl;base stems rot and black.

Control measures. Planting only whole and healthy tubers;Remove shrubs patients.

ring rot expressed wilting during flowering, and especially after it.The leaves curl and turn yellow.Scrub fade and fall apart.The tubers rot. Control measures. See. Blackleg.

Brown rot is a bacterial (slimy potato disease) manifested in the flowering stage of wilting leaves and stems on sunny days.Withering the leaves turn yellow and shrivel, and petioles and stems droop.Affected stems turn brown, the lower part of the Radical softens and rots, there is splitting along the stem. Control measures. crop rotation;removal of plant residues after harvesting potatoes and weeds during the growing season, the use of seeds only healthy and whole tubers, removal of diseased plants crops with tubers.