Salinity effects on seedling growth and floral initiation in the tomato

Abstract

Tomato seedlings, cvs ‘Matador’ and ‘Revido’, were irrigated on alternate days with one of six solutions in which the EC was increased stepwise from 2 to 27 mS cm⁻¹ by the addition of NaCl to a standard complete nutrient solution. Plant height, leaf area and shoot fresh and dry weight were significantly reduced by increasing nutrient solution EC after 12 days of treatment. A significant interaction between cultivar and nutrient solution salinity was found for fresh and dry weights, the weight reduction with increasing salinity being greater for ‘Revido’ than for ‘Matador’. No interaction was found for plant height or leaf area. A greater reduction in fresh weight than in dry weight resulted in increased dry matter content with increasing salinity. Linear reductions in relative growth rate and rate of leaf initiation were found with increasing salinity. The number of leaves initiated prior to floral initiation was unaffected by nutrient solution salinity.

Key words:

• cultivar
• expansion growth
• floral initiation
• Lycopersicon esculentum
• salt stress
• sodium chloride

Notes

Present address: Lithuanian Institute of Horticulture, Laboratory of Plant Physiology, LT‐4335 Babtai, Lithuania