Effet du sel (NaCl) sur la germination de graines de légumineuses

Auteurs

    Esaïe Tsoata

Résumé

Man is increasingly cultivating poor soils. Some of these have high levels of salt, mainly NaCl. This is the case in the semi-arid regions of north Cameroon, along the Atlantic coast, and in areas where arable land has undergone secondary salinisation. Due to osmotic pressure of the saline solution, NaCl delays seed germination of both glycophytes and halophytes. The use of plants adapted to salty environments makes it possible to increase cultivated land areas in regions where the soil contains abnormally high concentrations of soluble salts. The seeds used in our experiment originated from a biotope either non-saline (Cajanus cajan L Millsp.) or saline (Phaseolus adenanthus G.F. Mey., and Vigna marina [Burm.] Merril.). After manual scarification and rinsing in distilled water, seeds were placed in Petri dishes containing moist filter paper. Each dish, containing 25 seeds, was supplemented daily with 5 ml of distilled water containing increasing concentrations of NaCl (0, 3, 6, 9, 12, 18 and 30 g/l). Germination took place in the dark at 25 ± 3° C, with a relative humidity of 78-93%. Germinated seeds were counted every day up to 6 days after sowing. Ungerminated seeds were then rinsed with water three times, and transferred to Petri dishes containing 5 ml distilled water. The percentage of seed germination was then measured after 24 and 48 hours. Seed swelling due to imbibition was not affected by the osmotic pressure of the medium. Germination of seeds was increasingly slowed down with increasing NaCl concentration. When seeds pretreated with NaCl were placed in distilled water, germination was high with low NaCl pretreatment, and low or nil with high salt pretreatment, thus reflecting a reversible effect in the former case, and a permanent effect in the latter. Differences of germination level between the three plant species investigated were not related to the salinity of their original biotope.

Affiliations

Université de Yaoundé I, Faculté des Sciences, Département de biologie et de physiologie végétales, Laboratoire de physiologie végétale, BP 812, Yaoundé, Cameroun.

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Publié

1995-05-01

Comment citer

Tsoata, E. (1995). Effet du sel (NaCl) sur la germination de graines de légumineuses. Cahiers Agricultures, 4(3), 207–209 (1). Consulté à l’adresse https://revues.cirad.fr/index.php/cahiers-agricultures/article/view/29886

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