Promotion of sunflower growth and water productivity using soil amendments under saline conditions

Abstract

An experimental field trial was conducted to evaluate the effects of adding gypsum, compost, and their combination on the characteristics of a salt-affected loamy sand soil and on sunflower growth and productivity thereon. The trial was carried out in a reclaimed new area where sunflowers were sown according to standard practices and irrigated with water having a salinity of 2.7 dS m−1. The applied treatments were: untreated soil as a control (T1), gypsum at 1 ton per feddan (T2), gypsum (T2) plus compost at 5 tons per feddan (T3), gypsum (T2) plus compost at 10 tons per feddan (T4), and gypsum (T2) plus compost at 15 tons per feddan (T5). The results demonstrated that the incorporation of gypsum and compost significantly improved the soil properties, including pH, electrical conductivity (EC), soluble ions, and sodium adsorption ratio (SAR). Plant growth metrics such as height, head diameter, stem diameter, head dry weight, 100-seed weight, and seed weight per plant were notably enhanced in the treated soils compared with the control. Among the treatments, the combination of gypsum and compost at 15 tons per feddan (T5) yielded the most significant improvements in plant growth. Water productivity of sunflower increased significantly with increasing compost rates plus applying gypsum. This finding indicates the significance of the dual application of compost and gypsum in soil reclamation which could be more beneficial to sustain soil productivity than using gypsum solely. However, the specific quality and quantity of amendments should be tailored to the soil characteristics and the tolerance of the crops being cultivated. Further research is needed in diverse pedoclimatic conditions to develop region-specific soil management strategies.

Keywords

• Soil amendments
• salinity conditions
• water use efficiency
• sun flower