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Soil salinity severely affects cultivation in arid and semi-arid regions. It causes, among other things, an imbalance in the mineral nutrition of plants which results in yields' decrease. One of the research's approaches to mitigate the effects of these constraints is to look at the interaction between sodium chloride and phosphorus. The aim is to study the action of phosphorus to reduce the harmful effects of salinity. This study was undertaken in a greenhouse, in a pot of vegetation. The model plant used is Sorghum (Sorghum vulgar var rocket). The interaction NaCl (S) × P is carried out with four concentrations of NaCl (S0 = 0.1 dS m−1, S1 = 2 dS m−1, S2 = 8 dS m−1, S3 = 32 dS m−1) and four doses of TSP (PO = 0 mg/pot, P1 = 200 mg/pot, P2 = 400 mg/pot, P3 = 819 mg/pot), that is 16 (SP) processing. The results obtained made it possible to identify the effect of the SP processing on the morphological parameters, on the assimilation of the NPK's major elements, and on the accumulation of proline. They clearly showed that by adding phosphorus there was a remarkable improvement as the Sorghum displayed tolerance towards salinity. This improvement is manifested by an increase in stem height, dry material yield, nitrogen and phosphorus uptake, and proline accumulation. The results obtained suggest that Sorghum culture in saline medium (EC ≤ 32 dS m−1) is possible. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the rhizobial symbiosis and carbon (C) and nitrogen (N) accumulations in soil and plants in intercropping versus sole cropping in biennial rotation of a cereal - durum wheat (Triticum durum Desf.), and a N2-fixing legume - faba bean (Viciafaba L.) over a three-year period at the INRA (National Institue of Agronomic Research) experimental station in the Mauguio district, south-east of Montpellier, France. Plant growth, nodulation and efficiency in the use of rhizobial symbiosis (EURS) for the legume, nitrogen nutrition index (NNI) for the cereal, and N and C accumulation in the soil were evaluated. Shoot dry weight (SDW) and NNI were significantly higher for intercropped than for the sole cropped wheat whereas there was no significant difference on SDW between the intercropped and sole cropped faba beans. EURS was higher in intercropped than in sole cropped faba bean. Furthermore, by comparison with a weeded fallow, there was a significant increase in soil C and N content over the three-year period of intercropping and sole cropping within the biennial rotation. It is concluded that intercropping increases the N nutrition of wheat by increasing the availability of soil-N for wheat. This increase may be due to a lower interspecific competition between legume and wheat than intra-specific competition between wheat plants, thanks to the compensation that the legume can achieve by fixing the atmospheric nitrogen. [ABSTRACT FROM AUTHOR]

A total of 160 samples of 13 types of fresh fruits and vegetables from domestic production and import were analysed to detect the presence of pesticide residues. Analysis was performed by multi-residual extraction followed by gas chromatography–mass spectrometry. In 42.5% of the tested samples, no residues were found and 12.5% of samples contained pesticide residues above maximum residue limits. Risk assessment for long-term exposure was done for all pesticides detected in this study. Except chlorpyrifos and lambda-cyhalothrin, exposure to pesticides from vegetables and fruits was below 1% of the acceptable daily intake. Short-term exposure assessment revealed that in seven pesticide/commodity combinations, including three pesticides (chlorpyrifos, deltamethrin and lambda-cyhalothrin), the acute reference dose had been exceeded. [ABSTRACT FROM PUBLISHER]

Twenty landraces of cowpea (Vigna unguiculata (L.) Walp.) scattered throughout Algeria were compared through morphological and genetic characterization. At the morphological level, for qualitative characters there was no intra-landrace variation and for quantitative characters the variations were low except for landrace NAG2 Three different cultigroups were located in Algeria: Biflora that was dominant in the Sahara, Melanophtalmus in the North and Unguiculata including one landrace in Kabylia and two in Sahara. The AMOVA analysis indicated that the genetic variation was lower within than among agro-ecological regions. A Mantel test, revealed a correlation between the qualitative morphological data and the geographical data (R = 0.28; P < 0.01), indicating that the degree of morphological change among landraces was roughly proportional to the geographical distances separating them. Genetic diversity was analyzed by using 11 random amplified polymorphic DNA (RAPD) and 12 intersimple sequence repeat (ISSR) markers. No intralandrace variability was found. The eleven RAPD primers yielded 77 bands, of which 45 (58.44%) were polymorphic; the genetic similarity ranged from 66.0 to 96.7%. The twelve ISSR primers provided a total of 104 bands, of which 65 (62.5%) were polymorphic; the genetic similarity ranged from 62.8 to 97.8%. cluster analysis showed a good match between genetic background and geographical distribution, which was confirmed by the results of the Mantel test. In particular, geographical data and genetic data were found to be correlated: (R = 0.33; P<0.01) for RAPD, (R = 0.37; P < 0.01) for ISSR, and (R = 0.33; P < 0.01) for a combined RAPD-ISSR dataset. Moreover, despite the absence of significant correlation between morphological and RAPD data (R = 0.14; P = 0.14), significant correlations between morphological data and both ISSR (R = 0.27, P<0.05) and a combined RAPD-ISSR dataset (R = 0.22, P < 0.05) were noted. ISSR markers were better linked to morphological variation than were RAPD markers. However, despite this, genetic distances among these landraces were found to be essentially the same no matter which markers were used. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]