Megastigmus wasp damage to seeds of Schinus molle, Peruvian pepper tree, across a rainfall gradient in South Africa: implications for invasiveness

The Peruvian Peppertree (Schinus molle L.) is an evergreen tree native to semiarid environments of Peru and Bolivia in South America. This tree has been introduced and widely planted for ornamental and forestry purposes in several semiarid regions of the world because its seedlings are easily established and have a high survival rate; it also grows quickly, and it is tolerant of dry climates. We compared the global and regional niches of naturalized and planted populations of S. molle in order to examine the invasive stages and potential distribution of this species in four regions of the world. This work provides a novel approach for understanding the invasion dynamics of S. molle in these areas and elucidates the ecological processes that bring about such invasions. Most naturalized and planted populations were found to be in equilibrium with the environment. In its native range as well as in Australia and South Africa the models of the coverage area of habitat suitability for natural populations were the highest, whereas the coverage area of planted populations was lower. For planted populations in Australia and South Africa, a large percentage of predicted presences fell within sink populations. The invasion stages of S. molle vary across regions in its adventive range; this result may be attributable to residence time as well as climatic and anthropic factors that have contributed to the spread of populations.

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Enhanced Antifungal Effect of Chitosan/Pepper Tree (Schinus molle) Essential Oil Bionanocomposites on the Viability of Aspergillus parasiticus Spores

Journal of Nanomaterials ◽

10.1155/2016/6060137 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 26

Author(s):

Ana Guadalupe Luque-Alcaraz ◽

Mario Onofre Cortez-Rocha ◽

Carlos Arturo Velázquez-Contreras ◽

Ana Lilian Acosta-Silva ◽

Hisila del Carmen Santacruz-Ortega ◽

...

Keyword(s):

Essential Oil ◽

Zeta Potential ◽

Aspergillus Parasiticus ◽

Chemical Interaction ◽

Chitosan Nanoparticles ◽

Spherical Particles ◽

Schinus Molle ◽

Feasible Alternative ◽

Pepper Tree

Chitosan nanoparticles (CS) and chitosan/pepper tree (Schinus molle) essential oil (CS-EO) bionanocomposites were synthesized by nanoprecipitation method and the in vitro antifungal activity against Aspergillus parasiticus spores was evaluated. The shape and size were evaluated by scanning electron microscopy (SEM) and dynamic light scattering (DLS). The surface charge was determined by assessing the zeta potential and the inclusion of essential oil in bionanocomposites using Fourier transform infrared spectroscopy (FT-IR). The effect on cell viability of the fungus was evaluated using the XTT technique and morphometric analysis by image processing. SEM and DLS analysis indicated that spherical particles with larger diameters for CS-EO biocomposites were observed. Zeta potential values were higher (+11.1 ± 1.60 mV) for CS nanoparticles. Results suggest a chemical interaction between chitosan and pepper tree essential oil. The highest concentration of CS-EO complex caused a larger (40–50%) decrease in A. parasiticus viability. The inclusion of pepper tree oil in CS nanoparticles is a feasible alternative to obtain antifungal biocomposites, where the activity that each compound presents individually is strengthened.

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