Composting Animal and Plant Residues for Improving the Characteristics of a Clayey Soil and Enhancing the Productivity of Wheat Plant Grown Thereon

Wheat is a strategic crop in Egypt. Its local consumption is increasing continuously accordingly; Egypt has become the largest wheat importer worldwide. The sustainable approach for increasing wheat productivity is probably through organic additives. For this reason, animal, chicken and plant residues were collected from an experimental farm for preparation of (1) plant residue compost (PRC) via composting a mixture of air-dried and chopped rice and soybean straw at a rate of 1:1 and (2) animal residue compost (ARC) via composting a mixture of chicken and cattle manure at a rate of 1:1. The main aim of this study is to compare between the implications of amending a clayey soil with animal versus plant residues for improving soil physical and chemical characteristics. Also, this study considers the changes in soil fertility owing to these additives, hence their outcomes on wheat growth and productivity. To achieve this goal, a field investigation was conducted following a split-split design in which the two types of composts were plotted in main plots while the rates of compost application (15 and 25 Mg per hectare) were plotted in subplots. Non-amended control plots were also included for data comparison. All plots were cultivated with wheat seeds in winter 2018 and received the recommended doses of NPK fertilizers to compare between the two types of composts as conditioners not as fertilizers. The experiment lasted for 160 days until maturity. All composts improved considerably soil physical (soil bulk density, total porosity, saturated hydraulic conductivity and penetration resistance) and chemical (soil organic matter and CEC) characterises, especially with increasing their rate of application. In this concern, the results of the two types of composts were comparable. Also, these additives boosted grain and straw yields, yield components (spike length, spike weight, number of spikelets/ spike, 100-grain weight). Moreover, they enriched soils with N, P, K, Fe, Mn, Zn and Cu in available forms; hence raised their contents within wheat shoots and grains, with superiority for ARC versus PRC. There were significant positive correlations between shoot and grain yields in relation to the nutritional status of these plant parts. Accordingly, organic additives, especially animal residues, should be included in the coming sustainable approaches for increasing wheat production.