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Agriculture has new challenges against the climate change: the preservation of genetic resources and the rapid creation of new varieties better adapted to abiotic stress, specially salinity. In this context, the agronomic performance of 25 durum wheat (Triticum turgidum subsp. durum Desf.) genotypes (nineteen landraces and six improved varieties), cultivated in two semi-arid regions in the center area of Tunisia, were assessed. These sites (Echbika, 2.2 g l−1; Barrouta, 4.2 g l−1) differ by their degree of salinity of the water irrigation. The results showed that most of the agronomic traits (e.g. spike per meter square, thousand kernels weight and grain yield) were reduced by salinity. Durum wheat landraces, Mahmoudi and Hmira, and improved varieties, Maali and Om Rabia showed the widest adaptability to different quality of irrigation water. Genotypes including Jneh Kotifa and Arbi were estimated as stable genotypes under adverse conditions. Thereafter, salt-tolerant (Hmira and Jneh Khotifa) and the most cultivated high-yielding (Karim, Razzak and Khiar) genotypes were tested for their gynogenetic ability to obtain haploids and doubled haploid lines. Genotypes with good induction capacity had not necessarily a good capacity of regeneration of haploid plantlets. In our conditions, Hmira and Khiar exhibited the best gynogenetic ability (3.1% and 2.9% of haploid plantlets, respectively).

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The genetic variability is considered as the major principle of plant breeding for durum wheat. This variability can be induced in vitro by selection pressure exerted by stress factors such as salinity in order to regenerate the vitro plantlets tolerant. This study aims in the first step in the regeneration of plantlets tolerant to salinity from mature embryos culture derived from two Tunisian durum wheat varieties: improved (Razzek) and landrace (Jenah Khotifa (JK)) varieties. The tolerance evaluation to salt stress was applied in vitro (100 mmol•l −1 NaCl) and was based on various parameters. Our results showed that JK variety was distinguished by a stable response for all parameters tested: average weight of callus (368.1 mg for control and 307 mg under salt stress), callus regenerated percentage (36.6% for control and 35.7% under salt stress) and green shoots number/callus (17 for control and 17 under salt stress). This stability of response translates the adaptability of this variety to salinity. In order to fix regenerated JK plantlets in single generation and obtain HDs homozygous stable lines, in vitro gynogenesis technical is tested for this genotype. The Evaluation of gynogenetic capacity focused on about 1200 unfertilized ovaries of JK and was based on its ability to induction, differentiation, development of green shoots, and haploid plantlets regeneration. JK showed good tolerance to salinity and a relatively good response to gynogenesis.