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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]

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]

Color indices are important quality traits that define the consumer visual acceptance and agroindustrial preferences. Little is known regarding these properties in the commercial almond cultivars grown in Morocco. This work aimed at investigating kernel color indices in five cultivars, namely, "Fournat de Brézenaud," "Tuono," "Ferragnès," "Ferraduel," and "Marcona." Color indices consisted in the following: brightness (L∗), redness index (a∗), yellowness index (b∗), chroma (C∗), hue (H∗), and metric saturation (S∗). Measurements were performed over three consecutive growing seasons (2016–2018) across five different sites from northern (Aknoul, Bni Hadifa, and Tahar Souk) and eastern (Rislane and Sidi Bouhria) Morocco. All factors (cultivar, growing season, and site) affected significantly studied color properties; however, genotype was the main variability source. Wide variabilities were found among cultivars. "Marcona" showed the highest L∗, while "Ferragnès" and "Ferraduel" displayed greater scores of a∗, b∗, C∗, and S∗. Sidi Bouhria presented the lowest L∗ but higher a∗, H∗, and S∗. Moreover, Bni Hadifa displayed higher L∗, b∗, and C∗. 2016 (drier growing season) had the highest values of most indices. Principal component analyses (PCA) discriminate all factors through the first three components: PC1 (61%, genetic component) and PC2 (30%) and PC3 (7%) which were of environmental nature since they separate sites and growing seasons, respectively. Despite environmental effects, we suggested a possible discrimination among the studied cultivars based on their kernel color indices. Drought conditions during fruit development seemed to improve kernel quality via synthesis of pigments resulting in higher a∗ and b∗. [ABSTRACT FROM AUTHOR]

The development of high-yielding durum wheat genotypes requires the knowledge of the genetic variation for grain yield and its components. This study was performed to determine genetic gain and to evaluate the genotype × environment effect for grain yield and related traits in Moroccan durum wheat. A historical series of varieties developed during the last three decades was grown under two water regimes (rainfed and irrigated) during three growing seasons. Traits evaluated in the present work included grain yield, spikes per m2, kernels per spike, spikelets per spike, kernels per spikelet, spike length, kernel weight, plant height, harvest index, and fertile tillering. Results from ANOVA analyses revealed that grain yield and related traits were controlled to a large extent by water regime and growing season. Grain yield advance per year was estimated in 78 kg ha−1 under irrigated conditions, with no significant change under rainfed ones. Overall, the results indicated that most of the yield components changed by breeding activities during the last three decades. AMMI and joint regression analyses revealed that intermediate varieties have a wide adaptation, and old varieties were specifically acclimated to water-limit environments, while modern varieties were performed only under favorable conditions. [ABSTRACT FROM AUTHOR]

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 (Ψw), 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, Ψw 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, Ψw, 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, Ψw, E, gs, Fv/Fm and TCC, while all of these parameters were negatively linked to ProC and SSC. [ABSTRACT FROM AUTHOR]