Volatile Organic Compounds and Physiological Parameters as Markers of Potato (Solanum tuberosum L.) Infection with Phytopathogens

Abstract

The feasibility of early disease detection in potato seeds storage monitoring of volatile organic compounds (VOCs) and plant physiological markers was evaluated using 10 fungal and bacterial pathogens of potato in laboratory-scale experiments. Data analysis of HS-SPME-GC-MS revealed 130 compounds released from infected potatoes, including sesquiterpenes, dimethyl disulfide, 1,2,4-trimethylbenzene, 2,6,11-trimethyldodecane, benzothiazole, 3-octanol, and 2-butanol, which may have been associated with the activity of Fusarium sambucinum, Alternaria tenuissima and Pectobacterium carotovorum. In turn, acetic acid was detected in all infected samples. The criteria of selection for volatiles for possible use as incipient disease indicators were discussed in terms of potato physiology. The established physiological markers proved to demonstrate a negative effect of phytopathogens infecting seed potatoes not only on the kinetics of stem and root growth and the development of the entire root system, but also on gas exchange, chlorophyll content in leaves, and yield. The negative effect of phytopathogens on plant growth was dependent on the time of planting after infection. The research also showed different usefulness of VOCs and physiological markers as the indicators of the toxic effect of inoculated phytopathogens at different stages of plant development and their individual organs.

Spotting of Volatile Signatures through GC-MS Analysis of Bacterial and Fungal Infections in Stored Potatoes (Solanum tuberosum L.)

“…However, some volatiles that were common to all selected microbial (bacterial and fungal) infections, including butanoic butyl/ethyl ester, hexanoic ethyl/butyl ester and hexadecane, were not detected in healthy potatoes. Some overall (all storage temperatures) discriminative VOCs belonging to the PB culture were 1-butanol and 1-hexanol, which were also detected by Steglinska et al [20]. Their study revealed several VOC biomarkers, such as sesquiterpenes, dimethyl disulfide, 1,2,4trimethyl benzene, 2,6,11-trimethyl-dodecane, benzothiazole, 3-octanol and 2-butanol, associated with seed potatoes inoculated with Fusarium sambucinum, Alternaria tenuissima and Pectobacterium carotovorum during a three-month storage period.…”

Metabolite Formation by Fungal Pathogens of Potatoes (Solanum tuberosum L.) in the Presence of Bioprotective Agents

“…The microcosms were filled with 10 L of standard horticultural substrate mixed with a universal complete fertiliser containing macro- and microelements (YaraMila Complex; Yara) at a dose of 2 kg/m 3 . The plants were watered with tap water as needed throughout the growing season [ 40 , 41 ].…”

“…After potatoes were planted in microcosms, the growth and physiological activity of the plants were checked every 2 days for the first 24 days, and every 6 days for the remaining period [ 41 ]. The following parameters were measured: Biological condition of the seed potatoes—their vigour, turgor, rotting, and infection by phytopathogens [ 42 ]; The percentage of germinating tubers [ 42 ]; Growth kinetics of the plant, by measuring the length of shoots every 2 days during the first 24 days, and every 6 days for the remaining period [ 43 ]; Quality of the shoots on a five-point valuation scale, where 5 indicates shoots growing well, full of vigour, while 1 indicates dried out shoots [ 44 ]; Quality and growth kinetics of root, by measuring root length every 2 days until they reached 30 cm [ 42 ]; Growth kinetics of the root system, by assessing every 2 days the percentage of the soil profile area filled by the roots [ 45 ]; Quality of plants on a five-point rating scale, where 5 indicates plants with high vigour, coloured and growing properly, and 1 indicates dried out plants [ 8 ]; Intensity of gas exchange (transpiration, net photosynthesis, intercellular CO 2 content, and stomata conductivity), measured with a TPS-2 apparatus (PP Systems, USA) in the highest positioned fully developed leaves, during the period of most dynamic plant growth [ 39 ]; Index of chlorophyll content, measured with a Minolta SPAD-502 apparatus (Japan) in the highest positioned fully developed leaves, during the period of most dynamic plant growth [ 44 ].…”

Valorization of sorghum ash with digestate and biopreparations in the development biomass of plants in a closed production system of energy

“…Index of chlorophyll content in leaves was measured with the apparatus SPAD-502 (Japan) 34 . www.nature.com/scientificreports/ Activities of both phosphatase: pH 6; EC 3.1.3.2 and pH 7.5; EC 3.1.3.1 (U g −1 (FM) min −1 ), and RNase (EC 3.1.27.5) (U g −1 (FM) min −1 ) were assessed according to the methods elaborated by Knypl and Kabzinska 35 .…”