Induction of potato (Solanum tuberosum L.) defense genes by French marigold (Tagetes patula L.) essential oil

When attacked, plants activate defense mechanisms including volatile emission. Besides havinga pest repellent effect, volatiles can induce defense response in surrounding unharmed plants.French marigold (Tagetes patula L.) essential oil (EO) was isolated from the above-ground partsof plants collected from nature by hydrodistillation using Clevenger apparatus. GC/MS analysisrevealed the presence of 42 compounds, of which 97% (32 compounds) have been identified.The monoterpene fraction was dominant (76.9%) with terpinolene (32.4%) and limonene (14.7%)as the most abundant compounds. In order to investigate the potential of marigold EO to inducethe defense of potato, we analyzed 3 genes related to the induced resistance (IR): pathogenesisrelated PR-2 and PR-5 genes, and proteinase inhibitor Pin2. The potato plants were exposed to EOvolatiles during 4, 8 and 12 h. Two leaves of EO-treated or untreated control plants were collected,and plants were then additionally injured by mechanically wounding leaves across the leaf surface.After 24 h of wounding, another two leaves from each plant were collected and expressionof the IR related genes was analyzed by qPCR method. EO induced altered expression of PR genes,while Pin2 wasn’t affected by the treatment. Mechanical wounding increased the expression ofall genes after 4 and 8 h of EO treatment, with up to 4-fold change in PR-2. However, in plantsexposed to EO for 12 h before wounding, the level of transcription in PR-2 and Pin2 was similar tothat detected in untreated controls. These findings support the efforts for environmentally-safepest control in crops by using natural compounds.Uzelac B, editor. Book of abstracts. 3rd International Conference on Plant Biology (22nd SPPS Meeting); 2018 Jun 9-12; Belgrade, Serbia. Belgrade: Serbian Plant Physiology Society; Institute for Biological Research "Siniša Stanković"; Faculty of Biology; 2018. p. 58

Supplementary data for the article: Stupar, S.; Dragićević, M.; Tešević, V.; Stanković-Jeremić, J.; Maksimović, V.; Ćosić, T.; Devrnja, N.; Tubić, L.; Cingel, A.; Vinterhalter, B.; Ninković, S.; Savić, J. Transcriptome Profiling of the Potato Exposed to French Marigold Essential Oil with a Special Emphasis on Leaf Starch Metabolism and Defense against Colorado Potato Beetle. Plants 2021, 10 (1), 172. https://doi.org/10.3390/plants10010172.

Supplementary material for: [https://doi.org/10.3390/plants10010172]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4499

UHPLC-OrbiTrap MS Characterization of Phenolic Profiles in French Marigold Extracts and Analysis of Their Antifeedant Activity against Colorado Potato Beetle

French marigold is an aromatic plant rich in polyphenolic secondary metabolites, which pesticidal potential was examined in this study. Ultra-high-performance liquid chromatography (UHPLC) connected with OrbiTrap mass spectrometer (MS) identified 113 phenolics and revealed the most detailed phytochemistry of French marigold published so far. Depending on plant material (flowers or leaves) and solvents used for extraction (water, methanol, dichloromethane), the phenolic composition varied. Methanol extract of flowers, with 89 identified phenolics and high antioxidant activity statistically comparable with positive control Trolox, was chosen for testing of antifeedant potential against the 3rd and 4th instars of Colorado potato beetle (CPB). A significant reduction in final body mass of 4th larval stage fed with potato leaves coated with methanol extract of flowers in the concentration of 10 mg/mL was observed (157.67 mg vs. 182.26 mg of controls fed with non-treated leaves). This caused delayed molting since treated larvae reached the maximal mass a day after controls and this delay persisted during the entire larval development. Continuous feeding caused a 25% decline in digestive proteolytic activity of the 4th instar in comparison to controls. The results suggest that French marigold methanol extract of flowers could be proposed as a promising antifeedant for CPB management, with an impact on the reduction in the environmental footprint associated with synthetic pesticide application

Beneficial implications of sugar beet proteinase inhibitor BvSTI on plant architecture and salt stress tolerance in Lotus corniculatus L.

Food demands of increasing human population dictate intensification of livestock production, however, environmental stresses could jeopardize producers' efforts. Forage legumes suffer from yield losses and poor nutritional status due to salinity increase of agricultural soils. As tools aimed to reduce negative impacts of biotic or abiotic stresses, proteinase inhibitors (PIs) have been promoted for biotechnological improvements. In order to increase tolerance of Lotus corniculatus L. to salt stress, serine PI, BvSTI, was introduced into this legume using Agrobacterium rhizogenes, with final transformation efficiency of 4.57%. PCR, DNA gel-blot, RT-PCR and in-gel protein activity assays confirmed the presence and activity of BvSTI products in transformed lines. Plants from three selected transgenic lines (21, 73 and 109) showed significant alterations in overall phenotypic appearance, corresponding to differences in BvSTI accumulation. Lines 73 and 109 showed up to 7.3-fold higher number of tillers and massive, up to 5.8-fold heavier roots than in nontransformed controls (NTC). Line 21 was phenotypically similar to NTC, accumulated less BvSTI transcripts and did not exhibit an additional band of recombinant trypsin inhibitor as seen in lines 73 and 109. Exposure of the transgenic lines to NaCl revealed different levels of salt stress susceptibility. The NaCl sensitivity index, based on morphological appearance and chlorophyll concentrations showed that lines 73 and 109 were significantly less affected by salinity than NTC or line 21. High level of BvSTI altered morphology and delayed salt stress related senescence, implicating BvSTI gene as a promising tool for salinity tolerance improvement trials in L. corniculatus