Drought can alter stem apex temperature and plant phenological development and it can then have an effect on the duration of the durum wheat stages. Thermal responses of plants to water stress are tentatively analysed as regards microclimate conditions by applying three different water treatments. Apex temperature measurements showed that they are related to radiation and that acceleration of apex development could be related to their increase.

In biorefining, the conversion of carbohydrates under subcritical water conditions is a field of extensive studies. In particular, the hydrothermal decomposition of benchmark C6- and C5-monosaccharides, i.e., D-glucose and D-xylose, into furanics and/or organic acids is fully considered. Herein, we propose to establish the fundamentals of the decomposition of D-glucose and D-xylose under subcritical water conditions in the presence of specific salts (i.e., NaCl and KI) and in seawater. Our results demonstrated that the introduction of inorganic salts was found to modify sugars dehydration yields. Different NaCl concentrations from 0.21 to 1.63 mol L −1 promoted the conversion of D-xylose to 2-furfural (2-F) from 28 to 44% (molar yield). NaCl also improved 5-hydroxymethylfurfural (5-HMF) generation from D-glucose as well as rehydration of 5-HMF to levulinic and formic acid. KI favored other pathways toward formic acid production from D-glucose, reaching 20% in the upper concentration. Compared to a solution of equivalent NaCl concentration, seawater enhanced selectivity toward lactic acid which was raised by 10% for both monosaccharides, and sugars conversion, especially for D-glucose whose conversion was increased by 20%. 5-HMF molar yield around 30% were achieved from D-glucose in seawater at 211°C and 20 bars after 15 min.

The impact of salt stress under different salinity level (0, 50, 100, 150, 200 mMol of NaCl) on ten genotypes of durum wheat namely: Werd Bled, Hmira, Bidi, Arbi, INRAT 69, Agili, Derbassi and Bayatha, Karim and Maali was conducted. Germination rate were recorded daily using radicle extrusion as a criterion. Morphological studies root length, shoot length, fresh weight and dry weight of root and shoot were also measured. Analysis of variance (ANOVA) showed that germination rate of durum wheat genotypes was significantly affected by the salt stress. Results show a reduction of germination rate in response to the highest dose of NaCl for almost all the varieties except for Maali and Derbassi durum wheat cultivar in case150 and 200 mMol concentrations. After 6 days of germination, these lines showed germination percentage respectively of 70 and 60% against a rate of 0% for Bidi AP4 and Bayatha. For morphological traits, the effect of varieties was highly significant (P<0.01) on almost traits measured expect shoot dry weight, root fresh weight and root dry weight. Results show that all studied traits were significantly (P<0.001) reduced due to salt stress. The data showed that different level of salinity significantly affected the growth attributes by reducing root and shoot length for salinity below 50 mMol NaCl. Fresh weight and dry weight of root and shoot were reduced significantly with subsequent treatment.

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