Isolation, Identification and Preservation of Pectinolytic Bacteria Pathogenic to Potato

Blackleg of potato plants and soft rot of tubers are caused by several species of pectinolytic bacteria from genera Pectobacterium and Dickeya. The text describes simple methods of isolating bacteria from symptomatic and symptomless organs of potato plants, their identification using Polymerase Chain Reaction (PCR) and preservati

Screening for Potato Resistance to Blackleg and Soft Rot

Two diseases of the potato, blackleg of potato plants and soft rot of tubers, are caused by several species of pectinolytic bacteria which belong to two genera: Pectobacterium and Dickeya. Resistance to these bacteria is polygenic and the expression of resistance in tubers and plants is only partially related, as well as strongly dependent on the aggressiveness of the bacteria and on environmental factors. Two methods of assessing tuber and stem tissue resistance of potato cultivars and breeding lines are described

Collection of Potato Viral Pathogens, Its Validation and Maintenance

IHAR – PIB collection of potato viral pathogens has been maintained since 1970s. Currently there are 258 isolates in the collection representing 12 potato viruses, named PVY, PVM, PVS, PLRV, PVA, PVX, PAMV, BMYV, TBRV, AMV, CMV and TRV. The viruses are maintained in potato plants in vivo in the greenhouse (246 isolates), in potato plantlets cultured in vitro (12 isolates), in frozen leaves (two copies each of the 246 isolates) and in freeze-dried tissue (234 isolates)

Susceptibility of potato cultivars to soft rot caused by Pectobacterium chrysanthemi

Pectobacterium chrysanthemi Ech (Burkholder et al. 1953) Brenner et al. 1973, Hauben et al. 1998, is the causal agent of two diseases of potato: blackleg and soft rot (1). Tuber rot of potato induced by Ech is a threat to potato cultivation in the tropics (2), but it is also found in the cooler climates (3). The diploid interspecific hybrid of Solanum spp., DG 88- 9, and 72 potato cultivars registered in Poland were evaluated for their susceptibility to Ech strain SCRI 4063 at two different temperatures, 30oC and 20oC. After incubation the width of decayed tissue was measured (in mm) in the widest part of vertically sliced tubers. All tubers of cultivars and the diploid clone were infected at a temperature 30oC, but not all were infected at a temperature 20oC. There were significant differences among cultivars in susceptibility to Ech. The statistical analysis of data (the width of decayed tissue at 30oC) obtained from 72 cultivars and one diploid clone has defined four groups (mean ± 95 % a confidential interval): I - 8 cultivars and the diploid clone poorly susceptible (9.0 ± 2.1), II - 17 cultivars moderately susceptible (13.2 ± 2.3), III - 36 cultivars susceptible (16.9 ± 2.1), IV - 11 cultivars strongly susceptible (19,9 ± 2,0). The cultivars, which were most susceptible at temperature 30oC, were more susceptible at temperature 20oC. The mean diameter of decayed tissue was 15.9 mm, with a range for individual cultivar from 7.7 mm to 22.0 mm. The diploid clone DG 88-9, used as resistant standard to tuber soft rot, showed the least infection with the mean value 7.2 mm. Tubers of 48 cultivars and the clone DG 88-9 did not show any symptoms of infection with Ech at a temperature 20oC. Tubers of 24 cultivars showed partial rotting, since symptoms of infection were observed for three to 10 inoculation sites out of 20 for each cultivar. It was observed that among 9 less infected cultivars at a temperature 30oC there was only one cultivar with symptoms of infection at a temperature 20oC. On the contrary, in the group of 11 cultivars highly infected cultivars at a temperature 30oC, 7 showed symptoms of infection at a temperature 20oC. The expression of potato resistance to bacteria Ech differs depending on the temperature. Temperature influences the bacterial growth rate as well as the wound-induced suberization and periderm formation in potato tubers. The wound healing occurs most rapidly at 25°C, and is delayed at 10 or 15°C, while a temperature of 35°C prevents the periderm formation and retards suberization (4). Our observations are in agreement with the statement of Perombelon et al. (5) that Ech could be a threat to potato in warmer countries but also in Central Europe due to warming climate.vokMyynti MTT Tietopalvelut 31600 Jokioine

Isolation of Proteins From Potato Tubers

Here we optimized an efficient and reproducible method for proteins isolation from potato tubers for quan-titative proteomic analysis, aimed at detection of differentially expressed proteins upon various experimental conditions