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In Morocco, the use of phosphate fertilizer in farming system represents a source of cadmium that accumulates in soil and would affect negatively the growth and yield. Cadmium toxicity decreases nutrients and water translocation and absorption, it leads to an increase in oxidative harm, affects the metabolism of plants, and inhibits plant morpho-physiology as well. This experiment was conducted to examine the impacts of various concentrations of Cd (0, 15, 30 mg leg-1) in the flag leaf of three hulless barley varieties: Assiya (Morocco), Tombari (Tunisia), and Gizal30 (Egypt). Several morpho-physiological parameters were measured at vegetative stage encompassing measurements like Flag leaf length (FLL), Flag leaf area (FLA), Flag leaf width (FLW), and Flag leaf dry weight (FLDW), water relative content (RWC), total chlorophyll content (SPAD), and Fluorescence (Fv/Fm). ANOVA analysis showed that all morphological traits (except for FLDW) were primarily affected by the variety effect (>62% of total variance). In contrast, the treatment of Cd largely influenced physiological traits (>90% of total variance). Moreover, the interaction between the two factors was in general of lower importance. Comparison among varieties showed significant differences for all traits. In fact, the Moroccan variety (Assiya) displayed the highest values for physiological and morphological parameters.

This study examines physiological and biochemical changes in three Moroccan varieties of young olive trees (Olea europaea L.) grown under three different water regimes (control, moderate stress and severe stress). Leaf relative water content (RWC), water potential (yw), transpiration rate (E), stomatal conductance (gs), maximum quantum efficiency of PSII (Fv/Fm), the contents of total chlorophyll (TCC), proline (ProC) and soluble sugars (SSC) were measured at the flowering stage during three growing seasons (2015, 2016 and 2017). ANOVA analyses showed that the effect of the water regime was predominant in all of the examined parameters, except for Fv/Fm, which was under the effect of both water regime and growing season. Impacts of variety and interactions were of lesser magnitude. Water deficit reduced E, yw and gs by 25%, while its effect on RWC and Fv/Fm was a decrease of about 7%; however, increases in SSC and ProC were more than 10%. Among the growing seasons, 2015 flowering displayed the lowest values for RWC, yw, E, gs, TCC and Fv/Fm, and the highest for ProC and SSC. Among plant varieties, no significant differences were observed. The three principal component (PC) axes accounted for 91% of total variance. PC1 was better explained by the water regime, while the growing season fitted PC3 variability. Correlation studies highlighted significant associations between most parameters. Positive relationships were found between RWC, yw, E, gs, Fv/Fm and TCC, while all of these parameters were negatively linked to ProC and SSC.

This paper describes the composition and quality characteristics of the "Moroccan Picholine" virgin olive oil (VOO) produced in Taza province (northern Morocco). Legal quality indices, pigments, total phenols, oxidative stability, and fatty acid composition were analyzed under the impact of three extraction systems (two phase [C2] and three phase [C3] centrifugation decanters and super‐pressure [SP]) in three production sites (Bni Frassen, Bouchfaa, and Taza) during three consecutive crop seasons (2014, 2015, and 2016). All the assessed parameters were largely affected by the extraction system. Indeed, the two phase centrifugation system provided the better quality of VOO with the lowest values of free fatty acids and oxidation indices and the highest amounts of oleic acid, carotenoids, and total phenols therefore the greatest oxidative stability. Crop season and production site had only significant impacts on some parameters. VOO produced in 2015 from Bni Frassen was richer on total phenols hence presented lower values of peroxide value. Principal component analysis (PCA) showed a clear separation along PC1 (58%) between C2 with better VOO characteristics from both C3 and SP, while PC2 (11%) allowed a net distinction of VOO produced in 2014 from those in 2015 and 2016. Moreover, the oxidative stability of the assessed VOO was found strongly related to total phenol and carotenoid contents as well as oleic/linoleic ratio. [ABSTRACT FROM AUTHOR]

The activity of natural additives against the deterioration of virgin olive oil (VOO) in relation to storage time and conditions was examined. Thus, carotenoids and phenols previously extracted from carrot and olive mill wastewater, respectively, were added at 200 and 400 ppm to VOO and stored in clear and amber glass bottles at room temperatures during 120 days. The results showed that enriched VOO was largely influenced by the storage time, which resulted in a significant accumulation of hydrolysis and oxidation products. Storage conditions also affected considerably the enriched VOO. Dark glass bottles offered better protection against oxidative deterioration. The impact of both extracts on the oxidation status of examined VOO was significant and concentration-dependent. The natural additives markedly delayed the formation of hydroperoxides and conjugated dienes and trienes. Results from principal component analysis (PCA) showed that most of the variation was captured by the PC1 (89% of the total variance) which grouped samples in four categories according to storage times, each being divided into two clusters linked to storage conditions. Findings from this study revealed that natural additives could minimize VOO deterioration caused by storage time and conditions (light).

The purpose of this work is to evidence the effects of ripening index and water regime on the quantity and quality indices of “Moroccan Picholine” virgin olive oil (VOO) produced in northern Morocco. Olive trees were subjected to full irrigation and rainfed conditions, and olive fruits were collected at different ripening times. Results showed that the extracted volume of VOO increased during ripening, and decreased when full irrigation was applied. In regard to VOO quality, the statistical analysis revealed the predominant effect of ripening index on the majority of the considered parameters, except total phenols content that was strongly influenced by water regime. At more advanced stages of maturity, lower values of peroxide value, K232, carotenoids, chlorophylls and total phenols were registered while more free fatty acids were accumulated. Moreover, full irrigation reduced total phenols and increased free fatty acids, even if a great amount of pigment content was scored. Correlation studies showed significant relationships between pigments content and oxidation indices (peroxide value and K232).

Knowledge of the key physiological and biochemical traits related to genetic progress is essential to identify yield‐limiting factors and guide future breeding strategies. The aim of this research was to determine the rate of genetic gain in grain yield and physiological and biochemical traits in Moroccan durum wheat cultivars released from 1984 to 2007. Plants were subjected to two water regimes (irrigated and rainfed) during three growing seasons in order to identify those physiological and biochemical traits associated with grain yield. Grain yield (GY) and diverse physiological and biochemical traits known to be linked to mild drought stress were evaluated at anthesis and postanthesis. Physiological traits included stomatal conductance (gs), transpiration rate (E), chlorophyll fluorescence (Fv/Fm), chlorophyll content in flag leaf (SPAD), canopy temperature depression (CTD), and relative water content (RWC), whereas biochemical characteristics were leaf proline and water‐soluble carbohydrates (WSC) content. Grain yield tends to increase linearly under irrigated conditions with a genetic gain of 1.75% yr−1, in contrast, no significant change was observed under rainfed conditions. Traits that significantly increased over time were leaf proline content, gs, E, CTD, and SPAD. The changes in GY under irrigated conditions were largely explained by increases in gs during anthesis and postanthesis, CTD at postanthesis, and by leaf proline content at anthesis. Although genetic gains in GY under rainfed conditions could not be detected, leaf proline content and E were strongly associated to GY under these conditions, suggesting their usefulness as selection criteria for GY in water‐limited environments. Core Ideas: Modern Moroccan durum wheat varieties tend to be more sensitive to drought. No genetic gain in yield was found in Moroccan durum wheat evaluated under rainfed conditions. gs and leaf proline content tend to change over time in six Moroccan durum wheat cultivars. Yield was linked to gs, canopy temperature depression, and leaf proline content under irrigated conditions. Under rainfed conditions, grain yield was related to E and leaf proline content. [ABSTRACT FROM AUTHOR]

This work examined the influence of crop season, extraction system and production site on the composition of fresh olive mill wastewater collected from northern Morocco. ANOVA analysis showed that most of the traits were largely affected by the extraction system (≥60% of total variance). Comparison among extraction systems showed significant differences for all traits, except for chlorides. Three phase centrifugation system (C3) displayed the highest value of total phenols, while all the remaining traits were higher in two phase centrifugation system (C2). Concerning crop seasons, we noticed a general decrease in values of total solids, chemical oxygen demand, chlorides, C/N ratio and total aerobic mesophilic flora, from 2014 to 2016 season; in contrast, an increase in suspended solids, total kjeldahl nitrogen and proteins was detected. OMW with highest total phenols content and then more acidic were collected during 2015 season. Between production sites, Bni Frassen produced OMW with the highest values for salt and total phenols, but the lowest ones were obtained for microbiological traits. OMW from Taza were rich in total kjeldahl nitrogen and proteins. An increase in organic load indicators was observed in Bouchfaa. Principal component analysis (PCA) explained about 82% of total variability: 58%, 16% and 8% for principal component 1 (PC1), PC2 and PC3, respectively. Extraction system fitted the variability of PC1. PC2 was mainly explained by production sites, while PC3 separated crop seasons. Correlation studies showed significant relationships especially among the traits expressing organic load, while microbiological counts were largely associated to total phenols and pH. [ABSTRACT FROM AUTHOR]

Fresh olive oil mill wastewaters (OMW) were collected in northern Morocco from industrial mills operating with three extraction systems (two [C2] and three-phase [C3] centrifugation decanters and super-pressure system [SP]) during the 2017 growing season. Physicochemical and microbiological characteristics of these effluents were examined. OMW phenolic extracts were prepared and their antibacterial and antioxidant activities were evaluated. Moreover, the improvement of virgin olive oil stability with the addition of OMW phenolic extracts (at 100, 300 and 500 ppm) was investigated. Results from this work confirmed the pollutant load of these effluents characterised by an acidic pH, strong organic content, and considerable amounts of mineral matter. Concerning the microbiological counts, yeasts and moulds were the most abundant. Among the extraction system, C2 displayed OMW with the high levels for all measured parameters, except for the total phenols that were more abundant in C3. For the in vitro bioassays, OMW phenolic extracts showed a promising antibacterial activity against the two studied bacteria. In fact, C2 extract was the most active for inhibiting the bacteria growth, while Escherichia coli (Gram-) was more resistant to bactericidal phenols than Listeria innocua (Gram+). Findings from DPPH and FRAP tests showed a good antiradical potential and an important reducing power capacity and were both concentration-dependent. For the two tests, antioxidant activity of OMW phenolic extracts from C2 was also the most important. The addition of phenolic extracts to virgin olive oil, stocked at 60°C, resulted in lower records for peroxide value, K232 and K270 compared to the control, indicating a good protective effect against oil oxidation. The great antioxidant effect of OMW extracts was at 500 ppm, like that of ascorbic acid. [ABSTRACT FROM AUTHOR]