In the Nizhny Novgorod region, as part of pre-shipment monitoring, bacterial ring rot was detected in batches of ware potatoes with a total weight of 1.6 thousand tons.
Article continues below
Data on the results of the study were sent through the Argus-Laboratory information system to the Office of Rosselkhoznadzor for the Nizhny Novgorod Region and the Republic of Mari El to take response measures.
In total, since the beginning of the year, as part of these verification activities, specialists from the Nizhny Novgorod testing laboratory of the Federal State Budgetary Institution "ARRIAH" have analyzed for various indicators 8.6 thousand tons of potatoes produced in the Arzamas, Gorodetsky and Lyskovsky districts of the region, of which 5.6 thousand tons, including including, tested for infection with bacterial ring rot of potatoes.
The laboratory has conducted almost 400 studies.
The causative agent of ring rot is Clavibacter michiganensis subspsepedonicum.
It is very difficult to combat this pathogen, since it can remain asymptomatically in infected plants and tubers for a long time. Such latently infected tubers lead to the spread of the pathogen to regions where the disease was previously absent.
On the tuber, the disease is detected by a longitudinal section. The vascular ring is soft and yellowish in color. When the cut half of a tuber is squeezed, a light yellow mass emerges from the affected vessels, representing destroyed cells along with bacteria.
Later, the lesion may spread to adjacent tissues, including the core. The entire inside of the tuber rots and turns into a viscous, unpleasant-smelling mass.
Infection of tubers with bacteria occurs mainly in the field, in the early stages of tuberization. In this case, bacteria from the vessels of the diseased bush penetrate through the stolons into the vascular system of the tubers of the new crop.
The second route of infection is during the harvesting period, when the infection gets directly onto the tuber skin through direct contact with cut diseased tops or cut diseased tubers.
In this case, a pitted form of ring rot develops on the tubers during storage. On the peeled surface, round oily yellow spots measuring 2 to 3 mm in size are noticeable. They gradually increase to 1 to 1.5 cm in diameter.
The tuber tissue rots at the spots, resulting in the formation of pits. Bacterial ring rot is often confused with tuber lesions caused by a fungal infection, as well as those resulting from prolonged drought, leading to premature cell maturation and lignification of the vascular bundle (physiological browning of the vascular ring).
Only a laboratory analysis can tell about a specific potato disease. ■