As if the beleaguered potato and its growers don’t have enough diseases to contend with, a new potato disease was discovered by Chinese researchers on potato plants during the growing season and also on tubers during the storage period. The disease was identified in potatoes cultivated in Nileke County, Qitai County as well as other locations in Xinjiang province in China.
Scientists from Xinjiang Academy of Agricultural Sciences and Xinjiang Agricultural University report in the Journal of Integrative Agriculture that they isolated a pathogenic fungus which they were able to consistently isolate from infected potato plants as well as tubers. The pathogen was identified by the researchers as Galactomyces candidum F12, identified on the Atlantic potato variety.
The scientists say in their report that the leaves of the infected potato plants were found to be yellow and wrinkled with distinct wilted edges on the leaves. The diseased tubers showed a large number of depressions and several black lesions, as well as noticeable cracks.
According to the researchers, further study showed that the hyphae and conidia of the pathogenic fungus grew faster as the temperature was 30°C, pH was 7, soluble starch was used as optimal carbon source and yeast powder as optimal nitrogen source. In addition, 12 hour long continuous illumination with light was beneficial to the hyphal growth, while 24 hour continuous illumination was beneficial to the sporulation of the strain at a temperature of 30°C.
The research team concludes by noting that to their knowledge, this is the first report of Galactomyces candidum causing leaf wilt and postharvest tuber rot on potato in China. They are of the opinion that further studies on the pathogen are needed, including its host-specificity and ecological characteristics, as well as its relevant management strategies.
Source: Journal of Integrative Agriculture. Access the abstract and full paper online
Cover picture: Symptoms of diseased potato leaves and tubers | Journal of Integrative Agriculture