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Yield crops is a complex component depending on several grain filling traits. Knowledge of their relative contribution to grain yield determination under contrasting environments is essential to optimize grain yield and its stability. This study evaluates the changes resulting from durum wheat breeding in Morocco during the last three decades on grain filling rate (R) and duration (D), final grain weight (W), and days from sowing to anthesis (DSA). A set of six durum wheat varieties, released between 1984 and 2007, was grown in experiments conducted under contrasting environments during three growing seasons. The analysis of variance revealed that water regimes and growing seasons accounted for the largest percentages of variability for R, D, W, and DSA. D and DSA increased significantly over time under both water regimes. W exhibited an increasing trend under irrigated conditions, but a significant decline under rainfed ones. In contrast, the change of R was only significant under irrigated conditions. The path coefficient revealed that irrigated and rainfed conditions impacted differently the direct and indirect effects among traits with higher values of direct effects recorded under water-limited conditions. Within irrigated trials, R and D affected directly and positively grain yield. Regarding rainfed conditions, grain yield was only dependent on W. These findings indicate that genetic progress in grain filling traits and their direct and indirect effects on grain yield differed significantly between rainfed and irrigated conditions. Therefore, when selecting for high-yielding durum wheat genotypes, a particular attention should be paid to the environmental conditions.

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.

Drought is one of the main environmental factors affecting grain yield and plant architecture in durum wheat. The present work was conducted to evaluate the contribution of morphological traits above flag leaf node on grain yield of six Moroccan durum wheat varieties released between 1984 and 2007 and grown under two water regimes (irrigated and rainfed) during the 2015–2016 crop season. The following morphological traits were measured at anthesis: Flag leaf length (FLL), flag leaf area (FLA), peduncle length (PL), spike length (SL), spike area (SA), and green leaf area (GLA). Days from sowing to anthesis (DSA) and grain-filling period (GFP) were recorded. In addition, grain yield per plant (GYP) was evaluated at maturity. Analysis of variance showed the greater effect of water stress in explaining total variability of the studied traits. Mean comparisons indicated that water deficit significantly affected GYP and all morphological traits; it shortened DSA and GFP by 4 and 7 days, respectively. Moreover, GYP, DSA, and GFP increased in modern varieties. In contrast, FLL, FLA, and PL were reduced from old to modern varieties. Under irrigated conditions, correlation studies revealed that GYP was positively associated to GLA. Regarding the rainfed trial, GYP was positively correlated to FLL. Additionally, negative relationships were found between GYP and DSA in both water regimes. Stepwise regression highlighted the relative importance of each morphological traits on the stress susceptibility index, FLL was the most consistent trait entered the model followed by PL and FLA. In this study, some morphological traits above flag leaf node proved to be useful tools to select for grain yield in water-limited environments.

Almond [Prunus dulcis (Mill.) D.A. Webb] is one of the most important nut crops worldwide. It requires chilling during winter to break dormancy and develop fruiting buds. However, late winter chilling and early spring frosts may damage the reproductive tissues leading to productivity reduction. In the present work, we evaluated the frost susceptibility by means of chlorophyll fluorescence in flower buds of almonds cultivated in two different sites in Morocco: Aknoul in the north and Sidi Bouhria in the east. Five widely grown almond cultivars, namely Marcona, Fournat de Brezenaud, Ferragnes, Ferraduel, and Tuono, were involved in this study. Flower buds were incubated in temperatures of –3, –2, –1, 0, and 25 °C during 24 h and thereafter the Fv/Fm ratio was measured at the ovary zone. Combined analysis of variance showed that cultivar was the major source of variability, while site and cultivar by site interaction effects were of lesser extent and explained together less than 20%. At 25 °C, all cu...

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).

To produce nut virgin oils at a large scale, mechanical extractions have become widely accepted to obtain nut oils of higher quality without chemical residues. Little is known about kernel oil from the commercially grown almond cultivars in Morocco obtained by press extraction. This work was set up to evaluate effects of different environments on almond oil content (OC) and related quality traits, namely polyphenols (PP), saturated (SFA), monounsaturated (MUFA), polyunsaturated fatty acids (PUFA), and oleic/linoleic (O/L) ratio. To this end, the main cultivars were compared across various sites belonging to northern (typical Mediterranean climate) and the eastern Morocco (hot Mediterranean climate) over three growing seasons (2016–2018). Virgin oil achieved via mechanical press showed high quality as demonstrated by lower records of routinely measured parameters (acid value, peroxide value, and UV absorption coefficients K232 and K270) on one hand and higher records of PP and O/L on the other hand. Cultivars of longer fruit development period (FDP) such as ‘Marcona’ displayed higher OC, while ‘Tuono’ and ‘Fournat de Brezenaud’ (shorter FDP) presented the best record of PP. 2016 (the driest season) had the best scores of OC and PP. Eastern Morocco (relatively hot and dry) showed higher OC, PP, PUFA, but lower MUFA and, therefore, lower O/L. In conclusion, drier environments could enhance OC and foster the accumulation of more PP, PUFA but lower MUFA with a decreased oil stability.