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In the framework of the evaluation, valorization and conservation of plant genetic resources, six natural populations belonging to two species of forage grasses, perennial ryegrass (Lolium perenne L.) and annual ryegrass (Lolium rigidum Gaud.) collected in different agro-ecological regions of Algeria, were used to assess the effects of four NaCl and Na2SO4 concentrations (0, 50, 100, 150 mM) on germination parameters: germination percentage (GP), germination rate index (GRI), mean germination time (MGT), salt tolerance index (STI), seedling vigor index (SVI), shoot and root length. Seeds were germinated in an incubator at 20°C for 12 days in a completely randomized design with five replicates. The results revealed significant effects of NaCl and Na2SO4, populations and their interactions on germination parameters. Salinity reduced GP, STI, VI, GRI, shoot and root length, but increased MGT, in contrast to control experiment (0 mM). An important decrease was globally observed in the two species in all parameters with the lowest values at 100 and 150 mM except MGT. Compared to NaCl, the decrease was more important under Na2SO4. Population LP1 of L. perenne and the three populations of L. rigidum in the control and in the two salts showed the highest means of GP, GRI and SVI. Populations LR3 of L. rigidum (arid area) and LP3 of L. perenne (sub humid area) were the most sensitive at 150 mM. The shorter MGT was obtained in population LP1 of L. perenne which seems to be more salt-tolerant toward the two salts than the annual L. rigidum. [ABSTRACT FROM AUTHOR]

Variations in useful barley botanical traits are very important among others for improvement and food security. This study was done on 29 Algerian barley landraces from Sahara in presence of four controls and aimed to evaluate the variability among these barley genotypes through nine descriptive traits using Shannon-Weaver diversity index (H’). Results showed a great variation existing within the landraces for the majority of the traits studied. Indeed, high values of Shannon-Weaver diversity index were obtained for the curvature of first rachis segment (0.99), the pigmentation of awn tips (0.95), length of rachilla hair in grain (0.88), the disposition of lodicules in the fertile grain (0.85), lemma awn barbs (0.76) and spike density (0.61). H’ was intermediate for lemma type in grain (0.55) and was low for the glume length compared to grain and for the spike shape (0.33 and 0.44 respectively). The high diversity found for some important botanical traits related to seeds and spikes among barley cultivars open large perspectives for breeding programs on this germplasm and is beneficial for conservation, resiliency and for adapting to environmental variations especially those related to climate change. [ABSTRACT FROM AUTHOR]