Responses of Kenaf to Salt Stress: Germination and Vegetative Growth1

Abstract

The response of kenaf (Hibiscus cannabinus L.), a stem‐fiber plant, to salt stress was investigated during germination and early growth in solution culture under greenhouse conditions. Kenaf has been considered for use as a summer crop in areas with warm summers and low quality water. Germination was only slightly impaired by NaCl salinity up to 200 mmol L−1. Dry weight accumulation after 6 weeks growth was reduced 20 to 40% by 75 mmol L−1 NaCl (E.C. 7.8 dS m−1) and 70 to 80% by 150 mmol L−1 (E.C. 14.0 dS m−1). Vegetative development of the three cultivars, C‐108, G‐45, and E‐71, and the breeding line 15‐2X, were similar under these salt treatments. Rate of leaf emergence and leaf relative growth rate both declined linearly with increasing salt stress. Kenaf responds to salt stress by excluding Na+ from the shoot and partitioning Na+ and Cl− away from expanding leaf tissue. It is suggested that kenaf is suitable for cultivation with irrigation water of marginal quality but not in severely salt affected areas.