Little is known about how the performance of legumes symbiosis affects biomass and nutrient accumulation by intercropped cereals under the field condition. To assess the agricultural services of an intercropping system; durum wheat (Triticum turgidum durum L.cv. VITRON) and chickpea (Cicer arietinum L.cv. FLIP 90/13 C) were cultivated as both intercrops and sole cropping during two growing seasons under the field trial, to compare plant biomass, nodulation, N and phosphorus (P) uptake, and N nutrition index. Both the above-ground biomass and grain yield and consequently, the amount of N taken up by intercropped durum wheat increased significantly (44%, 48%, and 30%, respectively) compared with sole cropping during the two seasons. However, intercropping decreased P uptake by both durum wheat and chickpea. The efficiency in use of rhizobial symbiosis (EURS) for intercropped chickpea was significantly higher than for chickpea grown as sole cropping. The intercropped chickpea considerably increased N (49%) and P (75%) availability in durum wheat rhizosphere. In the case of chickpea shoot, the N nutrition (defined by the ratio between actual and critical N uptake by crop) and acquisition were higher in intercropping during only the first year of cropping. Moreover, biomass, grin yield, and resource (N and P) use efficiency were significantly improved, as indicated by higher land equivalent ratio (LER > 1) in intercropping over sole cropping treatments. Our findings suggest that change in the intercropped chickpea rhizosphere-induced parameters facilitated P and N uptake, above-ground biomass, grain yield, and land use efficiency for wheat crop.

As a result of a recent ad hoc prospection of the Algerian territory, a collection of peanut (groundnut; Arachis hypogaea L.) landraces was established, covering a remarkable array of diversity in terms of morphological and physiological features, as well as of adaptation to local bioclimatic conditions. In the present work, the oils extracted from the seeds of these landraces were evaluated in terms of edible properties and suitability for biodiesel production. As for edible use, a low free acidity (ranging from 0.62 to 1.21%) and a high oleic acid content (44.61-50.94%) were common features, although a poor stability to oxidation [high peroxide values, high spectrophotometric indices, and low % of inhibition in the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH)· test] was observed in a few cases. As for biodiesel production, low values of acidity [1.23-2.40 mg KOH (g oil)(-1)], low iodine values [90.70-101.54 g I2 (g oil)(-1)], high cetane numbers (56.95-58.88) and high calorific values (higher heating value 37.34-39.27 MJ kg(-1)) were measured. Edible properties and suitability for biodiesel production were discussed with respect to the German standard DIN 51605 for rapeseed oil and to the EN 14214 standard, respectively. One way ANOVA and Hierarchical Cluster Analysis showed significant differences among the oils from the Algerian peanut landraces.

Wheat–chickpea intercrops are not well studied, despite the importance of these two species in increasing agricultural profitability and ensuring nutritional and food security. The present study aims to assess the intercropping arable system’s services under contrasting field management and climate conditions. Simultaneously, this assessment focuses on the most agronomic and ecological indices widely used in the literature. Durum wheat (Triticum turgidum durum L.cv. VITRON) and chickpea (Cicer arietinum L.cv. FLIP 90/13 C) were cultivated, both in sole crop and intercrop during the 2018/2019 growing season. A field experiment was carried out under controlled conditions at three contrasting pedoclimatic sites and under three levels of N fertilization. Both grain and N yield of mixture crop were significantly higher (+11%) when chickpea and durum wheat were grown together under either low or moderate N application. Soil N availability as compared to the critical level increased by more than 19% from flowering to harvest stage for intercropped wheat under low N application (N-30 and N-60), while it decreased significantly for intercropped chickpea. In rich N soils and under low rainfall conditions (site 1 and 3), intercropping was generally more advantageous for yield (+14%), N yield (+23%), and land use (103 and 119.5% for grain and N yield, respectively) only with reduced N fertilization as assessed using both land equivalent ratio (LER) and land-use efficiency (LUE). Competition dominance was directly affected by changes in climatic conditions over sites; intercropped wheat was more competitive than their respective chickpea under low rainfall conditions. These findings illustrate the crucial role of competitive index assessment in intercropping to promise a robust method for crop N and yield diagnosis during fertilization decision-making.