Introduction. While researchers have paid considerable attention to the effect of soil salinity on crop yield, methodological impediments remain when salinity is combined with other growth factors, especially in farmers’ fields. A specific methodology was adapted to assess the effect of waterlogging and salinity on date palm yield (Phoenix dactylifera L. cv. Deglet Noor). Materials and methods. Date palm yield, water table depth, irrigation water, groundwater and soil salinity were measured in 167 field plots located in five irrigation sectors of the Wargla basin (Algeria). Variance analysis and a boundary line approach were combined to analyze actual and potential yields according to environmental stresses. Results and discussion. High soil salinity resulted from saline irrigation water and a shallow water table. Actual yield decreased with the increase in soil salinity, the decrease in water table depth, and the presence of a gypsum-cemented horizon within the soil profile. The significant effect of the interaction between water table depth and soil salinity showed that the crop responded to the most severe stress rather than to combinations of the individual effects. Potential yield was assessed according to classes of water table depth, soil salinity and the occurrence of a gypsum-cemented horizon. The relationship between soil salinity and potential yield was calibrated according to two models. The limiting factors in order of decreasing importance were shallow water table, high soil salinity and occurrence of a gypsum-cemented horizon for 38.3%, 16.8% and 2.4% of the field plots, respectively; there was no limiting factor for 42.5% of the field plots. In certain sectors, actual yields remained far below potential yields and the additional effect of irrigation water salinity could thus be considered.

Introduction. The introduction of the elite variety of black mulberry under saline conditions could have a significant long-term impact on development in the impoverished rural areas. Materials and methods. Plants of the Pakistan mulberry cultivar were propagated by budding on Japanese mulberry seedlings. Trees were cultivated under saline soil conditions in Egypt. Results and discussion. Trees successfully bloomed and produced fruits after 2 years of budding. Intensive flowering and fruiting occurred in the third seasons. Four to six catkins developed on each branch or spur. Each catkin consisted of an average of 315 flowerlets, stacked on a peduncle. Fruits were found to be parthenocarpic. During ripening, fruits changed from the green stage to the ruby-red stage, then to the dark-purple stage. Fruit ripening began in the second week of March and extended to the third week of April. Ripe fruit ranged from (7.3 to 11.8) cm in length and from (1.3 to 1.5) cm in diameter. Fruit weight ranged from (8.3 to 10.2) g. TSS of the fruit juice ranged from (13.0 to 17.5) °Brix, while pH ranged from 3.1 to 3.36. Fruits contained 10.2% carbohydrates, 1.4% protein and 1.2% fibers. Fruits were found to be a good source of iron, potassium, calcium and phosphorus. Fruits contained a medium level of vitamin C. Average crop production per tree in the second and third seasons was (51 and 96) kg, respectively. Ripe fruits could not survive more than 5 days’ storage at room temperature, but survived 3 weeks of cold storage.

Introduction. In saline soils, the water absorption process of the plants is negatively affected, due to the permeability of the roots, leading to hydric stress. Plants under saline stress close their stomas earlier than plants not in these conditions; this causes an increase in stomatal resistance due to the decrease in water potential. The aim of the present research was to detect alterations in the stomatic behaviour and leaf water potential in young plants of Annona squamosa submitted to saline stress. Materials and methods. Sixty-day-old seedlings of A. squamosa were acclimated for 15 days in a greenhouse, before being submitted to different saline treatments. Five treatments (T0 = 0 mM; T1 = 25 mM; T2 = 50 mM; T3 = 75 mM and T4 = 100 mM of NaCl in a nutritive solution) were applied with six replications. The evaluations of the stomatic response occurred on the 20th, 30th, 40th, 60th, 80th and 90th days after the beginning of the saline treatments. The transpiration measures, diffusive resistance and leaf temperature were registered in the first mature leaf. The photosynthetically active radiation, relative humidity and air temperature within the greenhouse were simultaneously assessed 60 and 90 days after the beginning of treatments; then the leaf water potential (Rleaf) was also measured. Results. During the time of the experiment the leaf temperature and its difference from the air temperature was not affected by NaCl levels, but only 90 days after the beginning of the treatments the values observed in the control plants were lower than those observed in the 25 mM treatment. The diffusive resistance after 40 days was increased in all NaCl treatments. The transpiration, independent of treatment, was reduced by 44.1% (at 60 days) and 13.4% (at 90 days) with the 100-mM treatment compared with the control treatment. The increment in NaCl induced a decrease in Rleaf in all treatments, but an equal reduction was observed for each treatment after 60 and 90 days. Conclusion. The NaCl levels affected the transpiration and leaf water potential; however, the leaf water potential showed an equal reduction in all treatments on the 60th and 90th days.