Effect of saline irrigation on growth characteristics and mineral composition of two local halophytes under Saudi environmental conditions.

A field experiment was carried out to determine the growth characteristics and mineral composition of two local halophytes (Atriplex halimus and Salvadora persica) under saline irrigation at Kind Abdulaziz City for Science and Technology (KACST), Research Station Al-Muzahmyia, Riyadh. The experiment treatments were one soil (sandy), four irrigation waters of different salinities (2000, 8000, 12000 and 16000 mg L(-1) TDS), two halophytes (Salvadora persica and Atriplex halimus) and one irrigation level (irrigation at 50% depletion of moisture at field capacity). Mean fresh biomass yield and fresh plant root weight of A. halimus increased while that of S. persica decreased significantly with increasing irrigation water salinity in all the treatments. Soil salinity increased significantly with increasing water salinity. A positive correlation (r = 0.987) existed between the irrigation water salinity and the soil salinity resulting from saline irrigation. The plant tissue protein contents increased in A. halimus, but decreased in S. persica with increasing irrigation water salinity. The Na ion uptake by plant roots was significantly less than K in A. halimus compared to S. persica which indicated adjustment of plants to high soil salinity and high Na ion concentration for better growth. The order of increasing salt tolerance was A. halimus > S. persica under the existing plant growing conditions. Among the two halophytes, A. halimus showed great potential for establishing gene banks of local species, because it has more forage value due to high protein contents than S. persica for range animals.