STUDIES OF SALINITY EFFECTS ON SOME SOIL PROPERTIES AND PLANT GROWTH

Abstract

Soil salinity is the most prevalent and wide spread problem limiting crop productivity in inigated agriculture. In field experiments, effects of different soil salinity levels in relation to some soil properties and on some plant parameters of the grown sugar beet and sunflower crops were studied along two successive seasons, in two different locations. For the two seasons, increasing soil salinity levels had a close association with the soil bulk density, total porosity, void ratio, air porosity, pore size distribution, and water retention or transmission. Such behaviour may be attributed to the colloidal nature of the soil particles, i.e, their valencies, charge, and densities in addition to relative hydrations of the adsorbed dominant cations. Also, increasing soil salinity level resulted in plant growth, yield and its quality parameters decreases of the grown sugar beet and Slll1flower crops under saline environments. The salinity threshold values, when yield begings to decline was found to be 3.0 Sd/m at the location I and 3.8 Sd/m for soils oflocation II soil salinity at ECe.::: 15. dS/m has been found to severely the yield of sugar beet yield up to 50%. Also the results indicat that sunflower crop seems to be more tolerant;::;. 12 dS/m reduction up to 50% compared to classification scheme. The negative conelation and association between soil salinity levels

and t te plant parameters of the studied soils were calculated and clearly defim d. The obtained results under the circumstances of the cutTent study reveald that the more pronounced effects of soil salinity on the plant parameters were found under the high levels of soil salinity. Also, the obtained results indicate the need to maintain low or moderate soil salinity levels which are essential lor maximum sugar beet and sunflower yield with satsifactory quality.