EFFECTS OF WATER SALINITY ON PLANT GROWTH AND WATER RELATIONS IN SNAP BEAN (PHASEOLUS VULGARIS L.)

The effects of four salinity levels (0%; 0.25% and 0.5% of NaCl) on leaf and root water status, plant growth and yield of snap bean grown on a clay-loam soil were studied.
The 0.5% treatment reduced leaf water potentials.
Total water potential showed a more pronounced decrease in the leaves (-1.2 of the 0.5% treatment vs. -0.9 MPa of the control) than in the roots (-0.6 vs. -0.5 MPa). The decrease in leaf osmotic potential was less severe (-1.4 vs. -1.3 MPa) and cuncurrentely the leaf turgor was reduced by 50% as compared to the control.
Salinity severely affected plant growth.
Root density was reduced by the 0.5% treatment (2.7 vs. 3.7 cm cm^-3 of the control). Under severe saline stress both leaf area and total above ground dry weight were reduced by 58%. In snap bean salt stress also significantly limited productivity since the 0.5% treatment decreased pod yield per plant by 85%. The shoot/root ratio was 40% higher in the control, which shows that water salinity in snap bean alters the pattern of dry matter distribution in the plant favouring the roots.

II International Symposium on Irrigation of Horticultural Crops

S. De Pascale, G. Barbieri, C. Ruggiero

Soil salinity, leaf growth, root growth, water potentials

https://doi.org/10.17660/ActaHortic.1997.449.90