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Atriplex nummularia has been extensively planted in Northern Africa to combat desertification. However, few studies evaluated the effectiveness of these interventions. This study aimed at assessing the dynamic performance of a number of Atriplex plantations located in the Marrakech province in terms of multitemporal dry biomass production. Three SPOT 5 images (2004, 2008 and 2012) and field biomass measurements were integrated to quantify the dry biomass production dynamics of plantations established from 1996 to 2007. Different plant ages covered the whole plant life cycle curve. Vegetation indices were derived from the images and those of 2012 were coupled to the measured biomass of 2012 to formulate biomass models. An analysis of shrub biomass production was conducted in plantations and in adjacent rangelands, covering varying degree of plant development, and an estimate of the economic benefits generated by the plantations in terms of available fodder biomass was performed. The results show that, on average, the plantation sites produced 2·21 to 3·61 Mg ha−1 of dry biomass more than the surrounding rangelands. The best performing plantations yielded even greater differences, up to more than 7 Mg ha−1. It was observed that the most performing plantations, while contributing to mitigating land degradation, have generated economic value and could compensate the economic cost of the intervention even under drought conditions. However, in several cases the plantation performance was far from sustainability, particularly due to poor management (early and/or over grazing), revealing that management is a critical factor for the success of this restoration practice. Copyright © 2014 John Wiley & Sons, Ltd.

The leaves and berries of myrtle (Myrtus communis L.) are rich in phenolic compounds, such as phenolic acids, flavonoids, and flavanols. The richness of these antioxidant compounds allows the potential use of myrtle biomasses as raw materials for medicinal and functional food products. Most of the phenolic compounds originate from the phenylpropanoid pathway, where phenylalanine ammonia lyase (PAL) enzyme activates the first step. The objective of this research is to study the activity of PAL as related to accumulation in the myrtle fruits and leaves of some phenolic compounds in the period between blossom and full berry ripening. With this aim, we compared two model genotypes with different fruit coloration. In leaves and berries of two cultivars, ‘Giovanna’ with pigmented berries and ‘Grazia’ with white berries, the PAL activity and content of polyphenols, anthocyanins, flavonoids, and tannins were determined with spectrophotometric methods. PAL activity was quite constant in leaves and variable in berries: Greater in berries of ‘Giovanna’ than in those of ‘Grazia’ cultivar, and increasing from berry color-break to full ripening. In berries, a positive correlation between PAL and flavonoids (r = 0.44), and between PAL and anthocyanins (r = 0.69), as well as a negative correlation between PAL and total polyphenols (r = −0.471), were found.

No abstract

Most of the biological properties of myrtle (Myrtus communis L.) are linked to the antioxidant activity of the phenolic compounds present in the extracts. In this study, the content of total phenols, tannins, and anthocyanins of acidified ethanol extracts of berries and leaves of five myrtle cultivars was quantified during the whole fruit development. In some development stages, the antioxidant activity (AA) of both tissues was evaluated with FRAP, ABTS, DPPH, β-carotene assays, and spectroscopic method (EPR). The trend of AA in leaf and berry extracts was different among genotypes and evaluation assays. In general, leaves showed with DPPH assay, the highest AA during autumn season, while with FRAP and β-carotene was higher at 120 DAF (days after flowering) corresponding to summer season. In berries, the AA with DPPH, ABTS, and EPR assays was the highest for all cultivars at 150 DAF and 210 DAF, while with β-carotene assay was higher in the first development stage. Both in leaf and berry, the total phenols and tannins contents influence the AA depending on the assay used, while the berries anthocyanins seem to play a minor role. The altitude of the site of origin differently affected the AA of myrtle leaf and berry. The study showed the potentiality to use the studied myrtle genotypes for further evaluation on biological applications of antioxidant activity.