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Forest Ecosystems
Published in Kezia Barker, Robert A. Francis, Routledge Handbook of Biosecurity and Invasive Species, 2021
Tommaso Sitzia, Thomas Campagnaro, Giuseppe Brundu, Massimo Faccoli, Alberto Santini, Bruce L. Webber
Most of these better-studied tropical regions, however, are in developed nations that only account for a relatively small proportion of tropical forests. Recent studies have shown that it is more likely that the lack of documented non-native invasive species impacts on tropical forests is merely because of a lack of knowledge rather than a fundamental difference from temperate forests. On the island of Borneo, Padmanaba and Sheil (2014) found that the spread of the introduced spiked pepper (Piper aduncum L.) tracked the installation of logging roads through the rainforest while Döbert et al. (2018) found low overall levels of invasion but a strong positive relationship between logging and non-native plant biomass and leaf area index. It can therefore be expected that the current increase in logging and plantation activities in tropical forests will significantly increase the risk of plant invasions, with potential long-term implications for their successional trajectory (Padmanaba and Corlett, 2014; Brown and Gurevitch, 2004; Friday et al., 2008).
Environmental Factors Impacting Bioactive Metabolite Accumulation in Brazilian Medicinal Plants
Published in Luzia Valentina Modolo, Mary Ann Foglio, Brazilian Medicinal Plants, 2019
Camila Fernanda de Oliveira Junkes, Franciele Antonia Neis, Fernanda de Costa, Anna Carolina Alves Yendo, Arthur Germano Fett-Neto
Piper aduncum L., the monkey-pepper, is an essential oil source, with biological activities, which include insecticidal, antimicrobial and larvicidal, among others. Pacheco et al. (2016) evaluated the effect of different light conditions on production and profile of essential oil constituents of leaves and roots of the species. Major compounds in the oil increased under an environment rich in blue light. Leaves were rich in E-nerolidol, linalol, α-humulene, cis-cadin-4-en-7-ol and caryophyllene, whereas roots had mostly apiol. While oil concentration of the former organs was stimulated by exposure to 50% reduction in sunlight, the latter were unaffected.
Lemongrass essential oil and its components cause effects on survival, locomotion, ingestion, and histological changes of the midgut in Anticarsia gemmatalis caterpillars
Published in Toxin Reviews, 2022
Angelica Plata-Rueda, Muhammad Fiaz, Bruno Pandelo Brügger, Veronica Cañas, Rogerio Pereira Coelho, José Cola Zanuncio, Luis Carlos Martínez, José Eduardo Serrão
The LEO and its most abundant components cause mortality, compromise locomotion and food consumption and histopathological changes in the midgut of the VBM caterpillars under laboratory conditions. The LEO, citral, and geranyl acetate were toxic to VBM and exerted a strong effect through oral exposure. The LEO and its components lead to VBM mortality in a concentration–dependent manner, as demonstrated in other Noctuidae caterpillars such as Mentha pulegium (Lamiaceae) to Anarta trifolii Hufnagel (Darabi and Khajehali 2017), Piper aduncum (Piperaceae) to Chrysodeixis includens Walker (Sanini et al. 2017), and Petroselinum crispum (Apiaceae) to Pseudaletia unipuncta Haworth (Sousa et al. 2015). The VBM caterpillars exposed to different concentrations of LEO or components reduced insect mobility, muscle contraction, unrecoverable paralysis, and consequently, death. In this context, symptoms in VBM were similar as caused by terpenoid neurotoxins found in plant essential oils (Keane and Ryan 1999, Enan 2001). The LD50 of three compounds here tested to VBM are low, ca. 10 µg insect−1, exhibit toxicity against caterpillars and mortality increase at higher concentrations, reinforcing their potential to control this pest.
Recent developments in biological aspects of chalcones: the odyssey continues
Published in Expert Opinion on Drug Discovery, 2019
Anu Rani, Amit Anand, Kewal Kumar, Vipan Kumar
1,3-diaryl-prop-2-en-1-ones, popularly known as chalcones are important core-structures belonging to the flavonoid family and act as synthetic precursors to various flavonoids and isoflavonoids [1]. Of the various forms they exist in nature, the molecular framework of chalcone includes the presence of aryl rings connected through a three carbon viz. α, β-unsaturated carbonyl chain (Figure 1) [2]. Chalcones, thus can exist in two isomeric forms viz. Z and E of which the E-isomer is considered as thermodynamically favorable [3]. The occurrence of chalcones in nature can be as they acknowledged are considered to be responsible for floral coloration, imparting yellow/red pigmentation because of their highly conjugated structures, thus attracting insects like bees and butterflies for pollination. Plants like Angelica keiskei, Glycyrrhiza inflate and Piper aduncum are rich source of chalcones and have been used extensively by the natives for their medicinal potential [2,4]. Besides, chalcones, because of their ease of synthesis, large number of replaceable hydrogens as well as ease of synthetic manipulations, have attracted the attention of organic medicinal chemists worldwide.
Acaricidal activities of essential oils against two-spotted spider mite, Tetranychus urticae Koch
Published in Toxin Reviews, 2018
S. G. Eswara Reddy, Shudh Kirti Dolma
Majority of EO and its constituents presently used as repellents, exploiting the association between oil constituents and repellent activity, reviewing the synergistic effects attained with the mixtures. The common monoterpenes such as limonene, α-pinene, cineole, eugenol, terpinolene, citronellol, citronellal, camphor and thymol present in the EOs are responsible of repellent activity reported in the literature. Our results are in conformity with the findings of other workers who reported repellent activity to T. urticae adults. The EO from leaves and fruits of Protium bahianum Daly showed promising repellent activity to adult T. urticae (Pontes et al., 2007,2010). Similarly, Piper aduncum L. oil showed 96% repellency to T. urticae which is due to (E)-nerolidol, α-humulene and β-caryophyllene (Araujo et al., 2012). EOs of Callistemon sieberi DC, E. bicostata, Eucalyptus ovata Labill, E. sideroxylon, Eucalyptus mannifera Mudie, E. dives, Eucalyptus elata (El), E. condonocarpa Blakely & Mc Kie, Kunzea ericoides (A. Rich) Joy Thomps, Melaleuca armillaris (Sol. ex Gaertn) Sm and Melaleuca fulgens R. Br. showed good repellency to adult T. urticae (Roh et al., 2013). In other study, M. pulegium at 1000 mg L−1 air also showed 100% repellency (Mozaffari et al., 2013) and Elettaria cardamomum L. at 7000 mg L−1 showed 67.9% repellency to adult T. urticae (Fatemikia et al., 2014). EO of Lavandula x intermedia Emeric ex Loisel and Hyssopus officinalis L. showed repellency (51% and 60%, respectively) to adult T. urticae (Salman et al., 2015). Sygygium aromaticum (L.) and M. spicata showed most potent repellency against adult T. urticae (Kheradmand et al., 2015). In a related studies against other insect pests, EO of Cedrus deodara (Roxb.), Tagetus minuta L. and Acorus calamus L. @10 mg mL−1 showed 48–65% repellency to third instar larvae of Plutella xylostella Linnaeus (Reddy et al., 2016). Other studies described the EOs of different plants showed repellent activity to Diptera (Ansari et al., 2000) and Coleopteron insects (Papachristos & Stamopoulos, 2002).