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Six varieties of barley (Hordeum vulgare), five of which were provided by ICARDA, were tested in a green house experiment for their salt tolerance. Afterwards the ICARDA variety Melusine, selected from this experiment for its combination of high yield and salt tolerance, was compared in a lysimeter experiment with the variety ISABON3, a very salt tolerant land race originally from Afghanistan. The variety ISABON3 showed a larger grain and straw yield under non-saline and saline conditions. The higher salt tolerance expressed itself during the growth period in: • a higher stomatal conductance during the irrigation interval; • a higher maximum osmotic potential; • a more vigorous growth, less affected by salinity; • no salinity effect on plant height and number of productive stems; • less salinity effect on water use efficiency. The less tolerant variety Melusine showed a better grain quality, expressed by its protein content that even slightly increased at increasing salinity against a decrease of the protein content of ISABON3. The varietal salt tolerance clearly affects the water use efficiency and the salt tolerance classification.

This work is a part of a research programme carried out by the Mediterranean Agronomic Institute of Bari (Bari institute) in cooperation with INRA (France) and ICARDA. The programme focuses on the degree of salt tolerance of various leg- uminous and cereal varieties widely cultivatedin the Mediterranean and Middle Eastern arid countries. The work was conducted under controlled conditions in the greenhouse of Bari lnstitute using plastic lysimeters. to investigate The impact of irrigation with saline water (EC values of 1, 4 and 8 dS/m) under two irrigation regimes (100% and 50% of evapotranspiration) on the growth parameters and yield of seven bread wheat varieties supplied by ICARDA was investigated. The findings of this research indicated that increasing the salinity level resulted in a gradual decrease in the grain production. However, the varieties under investigation could tolerate salinity level up to 8 dS/m with average losses not exceeding the 10% with respect to the fresh water treatment. The results also showed that deficit irrigation and the use of saline water as an irrigation source can have many advantages. The yield can be very near to the yield obtained under full irrigation. The vegetative growth is reduced, thereby lowering the consumptive water use. The cropping period is reduced leading to earlier crop maturity. The accumulated salts in soil are reduced to values nearly 50% lower than that where irrigation is practiced to totally compensate the evapo-transpiration which practically means the leaching requirements are being diminished. The substitution of fresh water by saline water for wheat production allows having a satisfactory yield and is an excellent fresh water saving exercise and by an environmentally sounding technique.

The salt tolerant variety Cham-1, created by ICARDA, showed a higher grain yield than the less salt tolerant landrace Haurani, but the main parameters for the pasta quality declined considerably. Salinity had a slight positive effect on the grain quality of the Cham-1 variety, whereas the Haurani variety showed no salinity effect on grain quality. A decrease in ash content corresponded with an increase in water use efficiency. The relationship between ash content and water use efficiency may be useful for selecting varieties with high water efficiency under saline conditions.

Seven varieties of durum wheat (Triticum turgidum), provided by ICARDA, were tested in a greenhouse experiment for their salt tolerance. Afterwards two varieties, differing in salt tolerance, were irrigated with waters of three different salinity levels in a lysimeter experiment to analyse their salt tolerance. The characteristics of the salt tolerant variety compared to the salt sensitive variety are: -a shorter growing season and earlier senescence; -a higher pre-dawn leaf water potential; -a stronger osmotic adjustment; -a better maintenance of the number of productive stems per plant. Salt tolerance of durum wheat corresponds with drought tolerance because the tolerance is caused by earlier senescence and stronger osmotic adjustment, both reducing the transpiration of the plant.

Two varieties of chickpea (Cicer arietinum L.) and faba bean (Vicia faba), differing in drought tolerance according to the classification of the International Center for Agronomic Research in Dry Areas (ICARDA), were irrigated with waters of three different salinity levels in a lysimeter experiment to analyse their salt tolerance. The drought-sensitive varieties are more salt tolerant than the drought-tolerant varieties. Under saline conditions, the drought-sensitive varieties show a much higher yield up to a salinity threshold, corresponding with an electrical conductivity (ECe) between 2.5 and 3 dS/m for chickpea and between 5.5 and 6 dS/m for faba bean. The drought-sensitive varieties are able to improve or maintain the water-use efficiency when irrigated with saline water. This ability can be ascribed to: •the larger biomass production owing to the later senescence, which allows a better utilization of the irrigation water; •the late flowering of chickpea.

Two chickpea varieties, differing in drought tolerance, were grown in lysimeters filled with clay, and were irrigated with waters of three different salinity levels. Under non-saline conditions, both varieties, slightly differing in pre-dawn leaf water potential during the growth period, gave almost the same yield. Salinity had a slight effect on the leaf water potential and the osmotic adjustment. Both were slightly higher for the drought tolerant variety, but much lower in comparison with sugar beet, tomato and lentil. The drought tolerant variety showed an earlier senescence in leaf and dry matter development and flowering which were accelerated by salinity. The drought sensitive variety, however, showed under slightly saline conditions (ECe=2.5 dS/m) from 135 days after sowing onwards a different behaviour by the growth of new leaves and flowers, a delay in senescence, leading to the same yield as under non-saline conditions. Under saline conditions (ECe=3.8 dS/m) the drought sensitive variety showed the same yield reduction of about 70% as the drought tolerant variety.

Two varieties of lentil were grown in tanks filled with clay, and were irrigated with waters containing three different levels of salinity. Salinity affected the germination and survival of the seedlings; the pre-dawn leaf-water potential and maximum osmotic adjustment; the development of leaf area, dry matter and number of flowers, and, finally, the yield. Lentil has a high water-use efficiency, about 2 kg m−3 under non-saline conditions, much higher than legumes such as broadbean and soybean. The crop, however, is much more salt sensitive and can only be grown on non-saline soils. At an ECe of 2 dS/m, the limit between non-saline and slightly saline soils, the yield reduction is about 20% and at an ECe of 3 dS/m it is 90–100%. The salt tolerance classification, made after a greenhouse experiment with nutritive solutions, was not confirmed by the experiments reported here.