Vascular discoloration and blackening of the underground stems may also be observed. If cracks appear in the ridge, earth up over them, Lift as soon as possible if blight appears in the crop and tubers are of usable size, Choose resistant cultivars. Mon – Fri | 9am – 5pm, Join the RHS today and support our charity. Arrows indicate diseased tissue. Pink rot of potato is an important soil-borne storage disease of potatoes worldwide. Infection occurs when germinating oospores, sporangia or zoospores penetrate the epidermis of underground portions of the plant. Phosphorus acid has some systemic activity and inhibits the growth of Phytophthora spp. This organism lives in the soil and infects potato roots, stolons, and tubers. In recent studies, Phostrol showed some promise for controlling pink rot. Transmission by infected seed tubers has always been considered of minor importance because rapid rotting and decay of tuber tissue during storage will exclude these tubers from being used as planting material. Author: Tuber decay begins at or near the stem or stolon end of the tuber. Tubers infected with pink rotturn pink after exposure to air for 15 to 30 minutes. Most infections in tubers will originate at the stem end (Figure 1 above). Significant problems often follow a wet growing season, particularly if the tubers are then lifted from wet soil. The fungus-like blight pathogen also affects tomato crops. Pink rot was first reported in the United States in Maine in 1938 and has become widely distributed in North America. The tuber skin (periderm) over the rotted portion is light brown in white-skinned cultivars. Potato rot nematode Ditylenchus destructor. Cause of Potato Dry Rot. Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. These varieties include Russet Norkotah, FL 1533, Red LaSoda, Dark Red Norland (often used as a susceptible standard), and NorDonna. This can be achieved by integrating all methods available for management of this disease, especially the use of cultural methods, and by following the guidelines laid out by the Fungicide Resistance Action Committee (http://www.potatodiseases.org/pdf/Fungicide-Resistance-Management.pdf). Irrigation water is also an important source of movement of the oospores from one location to another within a field and among nearby fields. Among the white-skinned cultivars, Red Norland and Nordonna were the least susceptible, and among the russet-skinned cultivars, Ranger Russet and Russet Burbank were the least susceptible. Pink rot (an oomycete) Phytophthora spp. Pink rot is a serious soil and tuber borne disease of potatoes common to many of the potato growing areas of Australia. However, the surface of healthy tubers may be contaminated with oospores that can be transferred to new locations. Oospores formed in infected tubers that were missed during harvest and remain unfrozen over the winter (volunteer potatoes) or in cull piles will end up in the soil after deterioration of the tubers (Fig. However, infected tissues are easily invaded by secondary pathogens, such as soft rot bacteria (Pectobacterium spp. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place. MSU is an affirmative-action, equal-opportunity employer. Breeding to develop potato cultivars that are resistant to pink rot has been limited because of the endemic nature of the disease and the relative success of chemical control with compounds such as metalaxyl in the 1970s and ‘80s. 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