Reports of the application of soil improvers, such as zeolite, microbes, and organic fertilizers, stated to provide better nutrition availability and improve the yield, as well as the nutritional content of crop plants’ edible parts. This study aimed to investigate the effect of different soil improvers on rice (Oryza sativa L.) yield and the iron (Fe) and zinc (Zn) content in the grain. The experiment proceeded according to a split-plot design with three replications under irrigated conditions. The experiment’s main factor was soil improvers comprising six types, i.e., inorganic fertilizer as baseline control, while the other treatments had additional microbes, organic fertilizers, zeolites, microbes + organic fertilizers, and microbes + zeolites. The sub-factor comprised five rice cultivars, i.e., Sembada Hitam, Sembada Merah, Inpari 47 WBC, Inpari Arumba, and Ciherang. The soil improvers and rice cultivars significantly affected grain yield. Additional organic fertilizer and zeolite maintained the rice yield; however, the combination of soil improvers did not necessarily increase the yield. Furthermore, the soil improver, especially zeolite, and the rice cultivars have a significant effect on increasing Fe and Zn content in rice grains. Sembada Merah tended to have higher grain Fe and Zn content across the soil improver treatments.
Rice (O. sativa L.), iron, microbes, organic fertilizers, pigmented rice, rice, soil improvers, yield, zeolite, Zn
Results showed the soil improver and rice (O. sativa L.) cultivars have a significant effect on rice yield and grain Fe and Zn content. Sembada Merah had the highest grain Fe and Zn content across various soil improver treatments. Zeolite may associate with the increase of rice grain Fe and Zn content.