A modified richard's equation for assessing the impact of drought and salinity in arid and semi-arid zones

Abstract EN

Drought and salinity onslaughts negatively affect plant physiological, morphological, and yield properties.

We assumed that both drought and salinity cause the same effect on plant growth and yield properties.

Accordingly, the additive effect was modeled.

A modified formula of Richard's equation was created assuming the similar assumptions between the macroscopic model and soil stress index model.

A split-split plot experimental design with four replications was used to conduct the research in Oraby Village, Maryout area, Alexandria, Egypt in the most dried year (2009/ 2010) to obsess the effect of silicon as a beneficial nutrient element on winter wheat especially under combined salinity and drought stresses.

The response of wheat (Triticum Aestivium l.

) cultivar, Sakha 94, to silicon doses added as potassium silicates and sodium silicates in three concentrations 0.0, 30.6 and 40.8 ppm silicon, was investigated.

All of them were foliarly sprayed at ages of 45, 60 and 75 days from seed emergence at early morning.

Moisture was tracked then the soil stress index model was derived, calculated, and discussed.

The effective relative extreme response function between soil stress index and plant stress index was developed.

The most interesting result is the ability of soil stress index to discriminate the type of water uptake under abiotic stresses conditions.

It has been noticed that soil stress index is a new powerful managerial tool for assessing the environmental impact of managing abiotic stress with silica fertilization in the studied area in Egypt.