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The content of nematicidal metabolites such as saponins, flavonoids and tannins in sulla (Hedysarum coronarium L.) suggests its potential nematicidal activity. In this study, the biocidal activity of 62.5–1000 μg mL−1 concentrations of flavonoid and tannin fractions from sulla was assessed in in vitro assays on the infective juveniles (J2) of the root-knot nematode (RKN) Meloidogyne incognita, while the suppressive effects of soil amendments with 10–40 g kg−1 soil rates of sulla biomass were investigated on potted tomato infested by M. incognita. The content of total nitrogen, carbon, flavonoids, tannins and saponins of sulla experimental material was also determined. After a 96-h exposure, more than 80% of the M. incognita J2 were killed even by a 125 µg mL−1 concentration of the flavonoid extract, while mortality peaked at 89% only at the 1000 µg mL−1 concentration of the tannin solution. Soil incorporation with sulla biomass significantly reduced the M. incognita densities both on tomato roots and in the soil, compared to either the non-treated control and chemical treatment with Fluopyram. The data confirmed the nematicidal potential of sulla, mainly due to its content of flavonoids and tannins, suggesting its suitability as green manure or a soil amendment for sustainable RKN management.

In this study, the relationship between nematicidal activity and chemical composition of ten essential oils (EOs) from different plant species was investigated both in in vitro assays on juveniles (J2) and eggs of the root-knot nematode Meloidogyne incognita and in experiments on tomato in soil infested by M. incognita. Nematode J2 were exposed for 4, 8 or 24 h to 0.78–100 μg mL−1 concentrations of each EO, whereas 24, 48 or 96 h exposures to 250, 500 and 1000 μg mL−1 solutions were tested on M. incognita egg masses. Treatments with 50, 100 or 200 μg kg soil rates of each EO were applied in the experiment on potted tomato. The highest nematicidal potential resulted for the C. verum EO, as highly toxic to both M. incognitaJ2 and eggs and strongly suppressive on nematode multiplication on tomato roots. The infestation of M. incognita on tomato roots was also strongly reduced by the EOs from E. citriodora and S. aromaticum, both highly toxic to M. incognitaJ2 but less active on nematode eggs. Adversely, R. graveolens EO strongly inhibited the egg hatch but was limitedly toxic to the infective J2. Chemical composition of the EOs was determined by GC-FID and GC-MS. The ten EOs showed a very different chemical composition in terms of major phytochemicals, with one or two dominant components totally amounting up to 85%. The structure–activity relationship based on the main phytochemicals identified in the assayed EOs and their nematicidal effects on M. incognita was also discussed. Results from this study confirmed that the selection of suitable EO raw materials can lead to the formulation on new effective nematicidal products.

Content of bioactive saponins of Medicago species suggests that they may also exert, as previously demonstrated on M. sativa, nematicidal properties exploitable for the formulation of new products for sustainable phytoparasitic nematode management. This study was addressed to highlight the bioactivity of saponins from five different Medicago species still poorly known for their biological efficacy, i.e., M. heyniana, M. hybrida, M. lupulina, M. murex and M. truncatula, against the plant parasitic nematodes Meloidogyne incognita, Xiphinema index and Globodera rostochiensis. The bioactivity of the extracts from the five Medicago species was assessed by in vitro assays on the juveniles (J2) and eggs of M. incognita and G. rostochiensis and the adult females of X. index. The suppressiveness to M. incognita of soil treatments with the Medicago plant biomasses was also investigated in a tomato experiment. The nematicidal activity of the five Medicago species was reported and discussed in relation to their phytochemical profile.

Lobularia maritima (L.) Desv. is a perennial herb growing wild in the Mediterranean basin. The aim of this work was to assess the fatty acid, terpene, phytosterol, and phenolic composition of the methanolic extract and its sub-fractions using Gas Chromatography-Mass Spectrometry (GC-MS), High-Performance Liquid Chromathography with Dioide-Array Detector (HPLC-DAD), High-Performance Liquid Chromathography-High Resolution Mass Spectrometry (HPLC-HRMS), and Electrospray Ionization Tandem Mass Spectrometry (ESI-MS/MS). The potential health benefits of this plant species have been investigated as well. The antioxidant activity was determined in vitro by means of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene bleaching tests. The inhibitory potential towards the production of the pro-inflammatory mediator nitric oxide was verified on lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cell line. A remarkable inhibitory activity was observed for the dichloromethane fraction, with an IC50 value equal to 45.86 ± 1.05 μg/mL, a significant result if compared to indomethacin and the known nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME), used as positive controls. Moreover, the ethyl acetate fraction proved to be effective in inhibiting pancreatic lipase, an enzyme that plays a pivotal role in the gastrointestinal digestion of dietary fat, suggesting that this species could potentially be a promising source of useful compounds for the treatment of obesity.