The objective of this study is quantifying the effect of different amendments (compost and geotextiles) and their appropriate additive method and levels of irrigation on the soil chemical properties and sorghum productivity (yield and plant NPK contents) grown on two soils (sandy and clay). Sandy and clay soil samples were collected from two locations in Menofia Governorate. A pot experiment was conducted using two the soils and two types of geotextiles (cotton and polyester) plus compost. Two methods of application have been tested (layering and mixing) under different amounts of irrigation water (100, 80 and 60% of field capacity) compared to the soil received no treatments (control)
The results indicated that, all treatments resulted in reducing soil pH, where the highest decreases were recorded in the soil received compost and the lowest were resulted from polyester application. In both sandy and clay soil, EC, OM and CEC values were increased with all additives in two application methods under the three irrigation levels compared to the control treatment. The highest increases of OM and CEC were recorded in the soil treated with compost, while the polyester addition was the lowest.
Wide range of fresh and dry matter yield of sorghum plants were observed, where the highest values of both fresh and dry weights were found with compost treatment followed by cotton application. At the three irrigation levels on sandy and clay soils, the method of mixed addition resulted in high fresh and dry weights of sorghum plants compared to the the layer addition.
Sorghum plants, concentration (%) and uptake (mg/pot) of N, P and K were promoted with the three added amendments in comparison with the control treatment. The highest contents (% and mg/pot) of sorghum plants in both sandy and clay soils at the same irrigation level were found with the mixed addition of amendments in comparison with that of layer addition. Generally, application of the three amendments with the two application methods, enhanced sorghum plants contents of N, P and K, especially with increasing irrigation level from 50 to 100% of FC. The influence of added amendments on enhancinf NOK contents followed the order: compost > cotton > polyester.