Emphasis on sustainable cassava production is increasing, with aims to increase the net income of cassava farmers in an ecologically friendly way. This study examined the optimization of soil fertilizer management at two research locations (Nampong and Seungsang) in northeastern Thailand. The experiment was conducted as a randomized complete block design with five replications. Eight different fertilizer management protocols consisted of (1) no fertilizer application (control), (2) the recommended dosage of chemical fertilizer (RDCF), (3) 3.12 t ha⁻¹ of chicken manure (CM), (4) 937.5 L ha⁻¹ of swine manure extract (SME), (5) CM + SME, (6) ½ RDCF + ½ CM, (7) ½ RDCF + ½ SME, and (8) CM + PGPR (stake soaking with PGPR solution). At the Nampong site, the application of CM + PGPR has the most potential for increasing the cassava yield in terms of the fresh tuber yield when compared with no fertilizer and RDCF applications. At the Seungsang site, the application of CM gave the high fresh tuber yield, without significant differences from RDCF applications. Furthermore, compared to the RDCF treatment, both soil fertilizer management protocols produced positive marginal rate of return values, showing clear potential for contributing to sustainable cassava production.

To optimize the quality and quantity of basil cultivars, this study investigated four varieties of nutrient-rich growing media compared with chemical fertilizers at the recommended dose in the soil-grown system, and commercial growing media (control) for producing holy basil and Genovese basil under greenhouse conditions. The experiment used a completely randomized design (CRD) with six treatments and five replications. With greater levels of chlorophyll, T3 and T4 growing media, consisting of top soil, filter cake, long-term/short-term composted chicken manure, coconut coir dust, and rice husk ash at a ratio of 3:2:2:1.5:1.5 v/v, produced the largest fresh yield when used for holy basil and Genovese basil productions, respectively. However, the net profit margin showed no discernible variations from T3–T5 and T2–T6 growing media, respectively. Nevertheless, T3 or T4 and T4 growing media were recommended for holy basil and Genovese basil production, respectively, based on highest productivity and intricacy of preparation, while also ensuring that the product retains its quality in terms of antioxidant bioactive components. In addition to maintaining the biomass of basil plants’ productivity even when they are cultivated in appropriate growing media, Genovese basil needs to be fertilized with organic fertilizer, like chicken manure, following the fifth or sixth harvesting period. Holy basil should be harvested after the fourth harvest period.