In vitro salinity tolerance screening of some legumes and forages cultivars

Abstract

The increasing water demand for dmestic and industrial water users in the water-scarce Mediterranean region is effecting the availbility of fresh water supplies for agriculture. Whereas much research has been done on the effect of irrigation with low-quality water on saline tolerant species, little is known about the salinity tolerance of legume and forage cultivars. The salinity tolerance of 200 lentil cultivars(Lens culinaris), 205 chickpea cultivars (Cicer arietinum) and five tall fescue cultivars (Fescua Arundinacea Schreb.) was tested in vitro, using four different salinity levels (0.5, 4, 7,10 dS/m). A second screening was done after pre-soaking the seeds for 24 hours in water (0.5 dS/m). The effect of X-ray (96 Kv, 200 mas,/sec, 5 sec interval) on the germination of lentil under these conditions was also tested. In addition, 21 promising lentil varieties were tested in sand-filled pots in the greenhouse. Average germination of the 200 lentil cultivars varied between 3% for the dry seeds at an EC of 10 dS/m to 59% for the pre-soaked seeds at an EC of 0.5 dS/m. For the 205 chickpea varieties germination varied between 40% for the dry seeds at an EC of 10 dS/m to 84% for the pre-soaked seeds at an EC of 0.5 dS/m.The experiment indicated that the chickpea cultivars were more saline tolerant than the lentil and tall fescue cultivars. The X-ray treatment had no clear effect on the germination and shoot growth of lentil. Results of the top 50 cultivars of each screening test indicated that even for the more resistant cultivars shoot growth becomes severly impaired at an EC of 4 dS/m and higher. In the greenhouse, 8 of the 21 pre-soaked lentil cultivars survived at an EC of 7 dS/m. The tall fescue cultivars did not survive the saline water treatment (4 dS/m and above). This study indicated that the chickpea cultivars were more saline tolerant than the lentil and tall fescue cultivars.