Schinus polygamus

Abstract: Galling sap-feeding insects are presumed to cause only minor changes in host plant tissues, because they usually do not require development of nutritive tissues for their own use. This premise was examined through comparison of the histometry, cytometry and anatomical development of non-galled leaves and galls of Calophya duvauae (Scott) (Hemiptera: Calophyidae) on Schinus polygamus (Cav.) Cabrera (Anacardiaceae). Cell fates changed from non-galled leaves to galls during the course of tissue differentiation. C. duvauae caused changes in dermal, ground, and vascular systems of the leaves of S. polygamus. Its feeding activity induced the homogenization of the parenchyma, and the neoformation of vascular bundles and trichomes. The histometric and cytometric data revealed compensatory effects of hyperplasia and cell hypertrophy in the epidermis, with hyperplasia predominating in the adaxial epidermis. There was a balance between these processes in the other tissues. Thus, we found major differences between the developmental pathways of non-galled leaves and galls. These changes were associated with phenotypic alterations related to shelter and appropriate microenvironmental conditions for the gall inducer. The nondifferentiation of a typical nutritive tissue in this case was compared to other non-phylogenetically related arthropod gall systems, and is suggested to result from convergence associated with the piercing feeding apparatus of the corresponding gall-inducer.

Abstract: Initial results of a long-term field experiment are presented for the above and below-ground biomass accumulation after two years, as well as root nodulation, nodule efficiency (g N fixed/g nodules) and biological N2 fixation (using the 15N isotope dilution method) of four N2-fixing tree species (NFTs) grown in the subhumid mediterranean-climate zone of central Chile. Two non-legume tree species, Fraxinus excelsior and Schinus polygamus, were used as reference plants for the isotope dilution calculations.

Abstract: Baccharis spicata (Asteraceae) and Schinus polygamus (Anacardiaceae) are plants native from Rio Grande do Sul and are hosts of two unidentified galling psyllids (Hemiptera, Psyllidae). Both plant species produce essential oil and their volatile compounds play an important role related to this kind of plant-insect interaction. Extraction and analysis of volatiles produced by leaves, galled leaves and galls were performed using headspace solid phase microextraction and gas chromatography coupled to mass spectrometry detector. Composition of the headspace of B. spicata and S. polygamus galls showed a significant change in their volatile profile when compared to healthy leaves. These changes were mainly related to a higher production of monoterpenes in galled tissue, compared to what was found in healthy samples. Some changes on the production of green leaf volatiles were also observed in both plant species, especially in S. polygamus. The possible ecological role of these chemical changes was discussed.

Abstract: Phytochemical investigation of the crude ethanol extract of the leaves of Schinus polygamus (Cav.) Cabrera (Anacardiaceae) results in isolation of eight compounds identified as triterpenoids, 3-O-acetyllupeol (I), βeta-sitosterol (II), lupeol (III). In addition to the polyphenols, gallic acid (IV), methyl gallate (V), quercetin-3-α-O-rhamnoside (VI), kaempferol (VII) and quercetin (VIII). In Egypt, degenerative diseases in general and toxic hepatitis in particular remain a serious public health problem. The hepatoprotective, curative and anti-oxidant properties of the major phytochemicals, compounds III and IV isolated from leaves of S. polygamus were investigated. Liver damage was induced by CCl4 (1 mlkg-1); a well-known toxicant and exposure to this chemical is known to induce oxidative stress and causes tissue damage by the formation of free radicals. Silymarin (25 mgkg-1) and vitamin E (7.5 mgkg-1) were used as standard drugs to compare hepatoprotective and antioxidant effects of the phytochemicals, respectively. Oral administration of 50 to 100 mgkg-1 body weight of compounds III and IV were significantly protected from CCl4 induced elevation in aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in adult male albino rats. The antioxidant effect in the liver was estimated by measuring the activity of antioxidant enzyme reduced glutathione. Detection of gallic acid and lupeol in S. polygamus as a member of family Anacardiaceae support the claim that both compounds could be considered as chemotaxonomic markers for plants belong to family Anacardiaceae. Results of the present study strongly reveal that both compounds III and IV have potent antioxidant and hepatoprotective effects against CCl4-induced hepatic intoxication. Key words: Schinus polygamus (Cav.) Cabrera, Anacardiaceae, triterpenes, phenolics, hepatoprotective, antioxidant effect.