Soil salinity and water status affect growth of Phoenix dactylifera seedlings

Abstract Effects of salinisation of soil on emergence, growth, and physiological attributes of seedlings of the date palm (Phoenix dactylifera) ‘Rati’ (Palmaceae) were studied. A mixture of chlorides and sulfates of Na, K, Ca, and Mg was added to the soil and salinity was maintained at 4.3, 6.0, 8.2, 10.5, 12.8, and 14.6 dS m–1. A negative relationship between percentage seed germination and salt concentration was obtained. Seedlings did not emerge when soil salinity exceeded 12.8 dS m–1. Results suggested that this species is salt tolerant at the seed germination stage. Seedlings survived and grew up to a soil salinity of 12.8 dS m–1 and evidently this species is salt tolerant at the seedling stage as well. Elongation of stem and root was retarded by increasing salt stress. However, this species has a tendency for rapid root penetration and roots are able to extract water from dry saline soil (6.0% moisture) below the permanent wilting percentage. Among the tissues, young roots and leaf tissue were most tolerant, whereas stem tissue was most sensitive to salt stress. This species is a halophyte and adapted to salt stress conditions by the evolution of an osmoregulation mechanism. However, osmoregulation is effective for salt tolerance only to a limited range in the continuum of salt stress. The ability of this plant to thrive in dry regions is further conferred by the xeromorphic features of its leaves.

[1]  J. B. Reid,et al.  Response of eucalypt species to drought , 1989 .

[2]  J. Etherington,et al.  Water Relations in Plants , 1969, Nature.

[3]  Homer C. Folks,et al.  Soils: An Introduction to Soils and Plant Growth , 1958 .

[4]  I. C. Gupta,et al.  Saline Wastelands Environment and Plant Growth , 1997 .

[5]  A. Pandey,et al.  EFFECT OF CHLORIDE SALINITY ON SURVIVAL AND GROWTH OF PROSOPIS CHILENSIS SEEDLINGS , 1997 .

[6]  J. Etherington.  Penetration of Dry Soil by Roots of Dactylis glomerata L. Clones Derived from Well-Drained and Poorly Drained Soils , 1987 .

[7]  H. Barrs,et al.  A Re-Examination of the Relative Turgidity Technique for Estimating Water Deficits in Leaves , 1962 .

[8]  L. Bernstein.  OSMOTIC ADJUSTMENT OF PLANTS TO SALINE MEDIA. I. STEADY STATE , 1961 .

[9]  P. C. Sharma,et al.  Salinity-fertility interaction on growth, mineral composition and nitrogen metabolism of Indian Mustard , 1993 .

[10]  A. Yeo.  Salinity resistance: Physiologies and prices , 1983 .

[11]  D. Pasternak.  Salt Tolerance and Crop Production-A Comprehensive Approach , 1987 .

[12]  R. Munns,et al.  Mechanisms of salt tolerance in nonhalophytes. , 1980 .

[13]  L. Bernstein.  OSMOTIC ADJUSTMENT OF PLANTS TO SALINE MEDIA. II. DYNAMIC PHASE , 1963 .

[14]  E. Epstein,et al.  Breeding and Selection for Salt Tolerance by the Incorporation of Wild Germplasm into a Domestic Tomato1 , 1981, Journal of the American Society for Horticultural Science.

[15]  A. Pandey,et al.  Effect of Salts on Germination of Seeds and Growth of Young Plants of Hordeum vulgare, Triticum aestivum, Cicer arietinum and Brassica juncea , 2000 .

[16]  A. Pandey,et al.  Desertification : a case study from Saurashtra region of Gujarat state of India , 1999 .

[17]  P. Kramer.  2 – Cell Water Relations , 1983 .

[18]  P. Troke,et al.  THE MECHANISM OF SALT TOLERANCE IN HALOPHYTES , 1977 .

[19]  J. P. Grime,et al.  A comparative study of root development using a simulated rock crevice , 1984 .

[20]  R. Dubey,et al.  Influence of NaCl salinity on the behaviour of protease, aminopeptidase and carboxypeptidase in rice seedlings in relation to salt tolerance. , 1990 .

[21]  L. M. Thompson,et al.  Soils and Soil Fertility , 1973 .