Antifungal and Insecticidal Activities of Selected Plant Species from Cloud Forest of Veracruz, Mexico: A Contribution to the Search of Novel Control Agents against Ambrosia Pest Complexes.

The antifungal and insecticidal activities of 34 extracts from 27 plant species were evaluated against fungal phytopathogens of the genus Fusarium and Xyleborus Scolytine ambrosia beetles involved in Fusarium dieback (FD) and laurel wilt (LW) diseases. Sixteen extracts caused mycelial growth inhibition (MGI) above 23 % at 2 mg mL-1 against F. solani, those from S. nudum and M. argyrophylla exhibited the highest MGI (57 % and 49 %, respectively). Thirteen extracts displayed significant antifungal activity against F. kuroshium, those from C. nocturnum and M. argyrophylla exhibited the highest MGI (100 % and 54.9 %, respectively). Additionally, ten plants extracts caused mortality in at least one of the beetle species tested, mainly from Solanaceae species. In the most active species, 39 phenolics were identified that may have contributed to their biological effects. This study is one of the first to report the potential of plant-derived natural products against the causative agents of FD and LW.

Identification of Antibacterial Phenolics in Selected Plant Species from Mexican Cloud Forest by Mass Spectrometry Dereplication.

Fifteen plant species from a protected cloud forest (CF) in Veracruz, Mexico, were screened for their in vitro capacity to inhibit the growth of the phytopathogenic bacteria Chryseobacterium sp., Pseudomonas cichorii, Pectobacterium carotovorum and Pantoea stewartii, causal agents of damage to crops like 'chayote', lettuce, potato and corn. As a result, the bioactivity of Turpinia insignis and Leandra cornoides is reported for the first time against Chryseobacterium sp. and P. cichorii. In addition, 24 and 18 compounds not described for these species were dereplicated by an UPLC/MS-MS method, respectively. The identified compounds included simple phenols, hydroxycinnamic acids, flavonoids and coumarins. The antibacterial assay of 12 of them demonstrated the bacteriostatic effect of vanillin, trans-cinnamic acid, scopoletin and umbelliferone against Chryseobacterium sp. These findings confirm for the first time the value of the CF plants from Veracruz as sources of bioactive natural products with antimicrobial properties against phytopathogenic bacteria.