EFFECT OF IRRIGATION WATER SALINITY ON GERMINATION AND GROWTH OF SOME MEDICINAL PLANTS WITHIN ARID REGIONS WEST OF IRAQI

Abstract

Two factorial experiments were conducted the first in the laboratory and the second in the green house according to complete randomized block design with three replicates, to study the effect of five levels of irrigation water varying in the electrical conductivity there are 1.4, 2.7, 4.1, 5.2 and 6.8 dS.m-1(W1, W2, W3, W4 and W5) respectively, on the germination and growth of three species of medicinal plants are coriander Coriandrum sativum L., cumin Nigella sativa L. and anise Pimpinella anisum L.(C, N and P) respectively, K+/Na+ ratio in plant tissue and salinity sensitivity rate index(Is) after three months from sowing plus to following soil salinity development as result to studied irrigation water used. The results showed highly significant differences were observed in germination degree, also the increasing in salinity of irrigation water was reduced the germination speed for all studied plant species, with superiority the anise and coriander in resistance to irrigation water salinity increasing in comparison with cumin which showed less salt tolerance. The results of greenhouse experiment showed same effected for irrigation water salinity on germination, also plants growth in the soil but with less degree on the studied species in comparison with laboratory experiment. W5 treatment showed the irrigation water salinity threshold for coriander associated with lower value for K+/Na+ ratio if we used this type of water to plants irrigation, with significant increasing in soil salinity.