Optimizing wheat growth and zinc uptake with compost and rice husk in alkaline conditions

Alkaline soils present significant challenges for sustainable agriculture, especially in regions where zinc deficiency limits both crop productivity and human nutrition. In this context, managing organic matter and micronutrient deficient soils is becoming a hot burning issue for the scientific community for ensuring both soil health and the food web. This study aims to investigate the potential impact of compost (CP), rice husk (RH), and zinc (Zn) amendments on zinc fortification in wheat (Triticum aestivum L.) cultivated in calcareous soils. The goal is to enhance the availability and uptake of zinc, thereby improving the nutritional quality of wheat grains. The experiment was conducted at the Ghazi University experimental farm, with eight treatments and three replicates. Each studied pot comprising 5 kg of sandy clay loam textured soil with "Akbar" variety of wheat as the test plant.

The results of the study revealed highly significant improvements in all measured traits. The combined application of compost, rice husk, and zinc led to substantial increases in plant height (19.9%), spike length (59%), number of spikelet's (36%), 1000-grain weight (24%), and grain zinc content (48.9%) compared to the control. Furthermore, significant enhancements in chlorophyll content, nitrogen, potassium, and zinc levels in the plant were estimated after Zn addition along with compost and rice husk.

The combination of RH with Zn exhibited the promising effects on wheat growth and yield. Moreover, the combined effect of RH and CP along with Zn expressed the highest performance in overall plant growth, increased soil organic matter, increased zinc concentrations in alkaline soil as well as in the grain of wheat. In addition, available phosphorus and potassium contents were also enhanced in zinc-deficient soil. This study provides the future directions to determine the effectual methods of Zn application for increasing the absorption and accumulation of Zn in wheat grains to address the human's demand.