Abstract
In order to isolate salt tolerant genotypes, response of 6 improved mulberry genotypes (Morus spp.) to salinity was studied under in vitro conditions by culturing axillary buds on MS medium containing 4 different concentrations, viz., 0.0, 0.25, 0.5 and 0.75% of NaCl having the EC values of 3.12, 9.6, 14.2, 18.6 mmhos/cm respectively. Except C776, none of the other varieties survived at 0.75% NaCl. All genotypes developed shoots at 0.25 and 0.5% NaCl. Suppression of shoot growth due to salt stress was observed in all genotypes except C776 and C763 at 0.5% of NaCl. No roots were formed beyond 0.2% NaCl. At lower concentrations of 0.1 and 0.2% NaCl rooting was observed in four genotypes. Among the genotypes screened C776 was comparatively more tolerant to NaCl for root formation. Thus, the genotype C776 was selected as salt tolerant. In order to confirm the result obtained in this study a field investigation was conducted on the coastal saline soils at Canning, West Bengal. The field performance also confirmed the salt tolerant nature of C776. Thus, from this study it could also be concluded that C776 is a salt tolerant mulberry genotype and also that in vitro screening through axillary bud culture is an easy and effective method for screening of large number of genotypes for salt tolerance in mulberry.
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