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Shoot and root growth and plant dry weight were determined for twenty four accessions of pearl millet, Pennisetum americanum (L.) Leeke, after two weeks growth in saline solution culture at EC 20 dS m[sup-1]. The EC was achieved using NaCl + CaCl[sub2] 1 : 1 by weight in solution culture. Although salinity markedly inhibited growth of all accessions, three, 93613, KAT/PM-2 Kitui, and Kitui local produced significantly greater dry matter, and they and 93612 had longer shoots than the other accessions. Accessions WCA 78 and Bulk 7704 were highly sensitive to salinity in all 3 characters measured. There was considerable variation between the 24 accessions, suggesting that selection for increased tolerance to salinity in pearl millet should be possible. This was examined using normal seed of the cultivar A1/3. A first cycle of selection screened 16,000 seeds after 15 days growth in nutrient solution at EC 26 dS m[sup-1]. 106 individuals were selected to form the S[sub1] selection line. Selected seedlings were grown to maturity and polycrossed. In a second cycle of selection, 30,000 S[sub1] polycross progeny were screened as previously, but at EC 30 dS m[sup-1]. A selection intensity of 0.08 % was achieved. The selected plants were again grown to maturity and again polycrossed. Efficiency of the selection procedure was assessed from comparison in sand culture of the performance of the selected line with the unselected A 1/3 line and Kitui local which from the previous assessment of the 24 accessions was rated as relatively salinity tolerant. The selection line was superior to the other two lines at four salinity levels. The results of this study suggest that further improvement in salinity tolerance in pearl millet may expected from further selection and breeding, using the methods described here. [ABSTRACT FROM AUTHOR]

Tolerance to sodium chloride in solution culture and its genetic basis has been assessed for populations of Festuca rubra L., Holcus lanatus L., Agrostis stolonifera L., and Dactylis glomerata L. from salt marsh, spray zone, and inland habitats. Two populations of F. rubra from salt marshes and one population of A. stolonifera from a spray zone showed significant NaC1 tolerance. However, in the main, responses of populations to increasing NaCl in the rooting medium showed little relationship with electrical conductivity or Na content of the soil. Narrow-sense heritability estimates were high for all populations, except for one F. rubra population from a salt marsh and the population of A. stolonifera from a spray zone. Broad-sense heritabilities were high for all populations suggesting high genetic components for variation in NaCl tolerance. [ABSTRACT FROM AUTHOR]