Bacillus licheniformis strain POT1 mediated polyphenol biosynthetic pathways genes activation and systemic resistance in potato plants against Alfalfa mosaic virus

Abstract

Alfalfa mosaic virus (AMV) is a worldwide distributed virus that has a very wide host range and causes significant crop losses of many economically important crops, including potato (Solanum tuberosum L.). In this study, the antiviral activity of Bacillus licheniformis strain POT1 against AMV on potato plants was evaluated. The dual foliar application of culture filtrate (CF), 24 h before and after AMV-inoculation, was the most effective treatment that showed 86.79% reduction of the viral accumulation level and improvement of different growth parameters. Moreover, HPLC analysis showed that a 20 polyphenolic compound was accumulated with a total amount of 7,218.86 and 1606.49 mg/kg in POT1-treated and non-treated plants, respectively. Additionally, the transcriptional analysis of thirteen genes controlling the phenylpropanoid, chlorogenic acid and flavonoid biosynthetic pathways revealed that most of the studied genes were induced after POT1 treatments. The stronger expression level of F3H, the key enzyme in flavonoid biosynthesis in plants, (588.133-fold) and AN2, anthocyanin 2 transcription factor, (97.005-fold) suggested that the accumulation flavonoid, especially anthocyanin, might play significant roles in plant defense against viral infection. Gas chromatography-mass spectrometry (GC-MS) analysis showed that pyrrolo[1,2-a]pyrazine-1,4-dione is the major compound in CF ethyl acetate extract, that is suggesting it acts as elicitor molecules for induction of systemic acquired resistance in potato plants. To our knowledge, this is the first study of biological control of AMV mediated by PGPR in potato plants.

Χαρακτηρισμός του Bacillus subtilis MBI600 ως παράγοντα βιολογικής καταπολέμησης φυτοπαθογόνων και επαγωγής της ανάπτυξης φυτών

“…strains to inhibit the mycelial growth of B. cinerea (Kefi et al, 2015;Jiang et al, 2019). Similarly, our in planta experiments on cucumbers plants showed that Bs MBI600 was able to efficiently control gray mold as has been observed previously with other Bacillus strains (Nie et al,2017;Abdelkhalek et al, 2020). These results underline that Bs MBI600 strain may be an effective biocontrol agent against B. cinerea in cucumber crops.…”

Volatile Nitrogenous Compounds from Bacteria: Source of Novel Bioactive Compounds

“…Pyrrolo-pyrazines are reported to be produced by both Gram-positive and Gram-negative bacteria commonly associated with bacterial species isolated from mangrove soils, plant rhizosphere, marine sediments, and sea sponges. [20][21][22][24][25][26] This group of compounds is related to many drugs currently used for the treatment of cancer, bacterial and fungal infections, high cholesterol and anti-viral, such as those used against HIV. [27,28] The large size and high boiling point of pyrrolopyrazines, compared to other compounds, make them less susceptible to volatilizing when subject to the temperatures used in the headspace (in Solid Phase Micro Extraction (SPME), for example), thus also making this class more prominent for liquid-liquid extraction (LLE).…”

“…[27,28] The large size and high boiling point of pyrrolopyrazines, compared to other compounds, make them less susceptible to volatilizing when subject to the temperatures used in the headspace (in Solid Phase Micro Extraction (SPME), for example), thus also making this class more prominent for liquid-liquid extraction (LLE). [26,[29][30][31][32][33][34] Approximately 34 articles describing pyrrolo-pyrazines from bacterial isolates were found in the scientific database (Table 1). However, not many described the purification and identification methods for nitrogenous compounds or their biological activity.…”

“…Pyrrolo‐pyrazines are aromatic nitrogenous compounds containing a pyrrolo‐pyrazine moiety, that is a pyrrole ring fused to a pyrazine ( Table 1, Figure 1). Pyrrolo‐pyrazines are reported to be produced by both Gram‐positive and Gram‐negative bacteria commonly associated with bacterial species isolated from mangrove soils, plant rhizosphere, marine sediments, and sea sponges [20–22,24–26] . This group of compounds is related to many drugs currently used for the treatment of cancer, bacterial and fungal infections, high cholesterol and anti‐viral, such as those used against HIV [27,28] …”

Purification and Cytopathological Effects of cucumber mosaic virus on Cucurbita pepo Plants

“…Plant diseases are to blame for significant crop output losses worldwide, posing substantial food security issues (Abdelkhalek and Hafez, 2020;Heflish et al, 2021). Plant viruses are the most critical pathogens in causing massive agricultural production difficulties once they appear in the field (Abdelkhalek et al, 2020a;Abdelkhalek and Sanan-Mishra, 2018;Hafez et al, 2014). Cucumber mosaic virus (CMV) belongs to the genus Cucumovirus and the family Bromoviridae (Scholthof et al, 2011).…”