Abstract:
Excessive use of chemical fertilizers in agriculture has raised serious environmental and health concerns. In response to the challenges, there is growing interest in sustainable agricultural practices, particularly the use of organic fertilizers. This study was conducted to evaluate the effect of organic fertilizer derived from dried Azolla, blended with Paddy husk ash (PHA) and Eppawala rock phosphate (ERP), on the growth and yield performance of the green chilli variety MICHHY01. The experiment was conducted as a pot trial at the Faculty of Technology, University of Ruhuna using a completely randomized design with four treatments each replicated four times. The treatments consisted of varying ratios of Azolla, ERP, and PHA as follows: T1 (control - 0:3:3), T2 (3:3:3), T3 (6:3:3), and T4 (9:3:3). The basal growing media was prepared by mixing compost, sand, and coir dust at a 2:1:1 ratio (v/v). Growth parameters, including plant height, number of leaves, branches, leaf length, leaf width, and stem diameter, were measured at two-week intervals. Yield parameters, such as number of days to first flowering, number of flowers, number of pods, pod length, pod girth, and fresh weight of pods, were also recorded. The results revealed that the application of Azolla-based fertilizer at a 9:3:3 ratio (T4) significantly enhanced (P<0.05) both vegetative growth and yield performance. T4 exhibited the highest plant height (88.25 ± 1.65 cm), number of leaves (196 ± 4.35), and number of branches (82 ± 4) at the harvesting stage. Additionally, T4 recorded the minimum number of days to first flowering (60.00 ± 0.00 days), the highest number of flowers per plant (84.25 ± 6.30), and the greatest number of pods per plant (45.75 ± 3.52). Pod characteristics, such as pod length (12.375 ± 0.11 cm) and girth (10.360 ± 0.15 mm), were also significantly improved under T4. Furthermore, the highest total yield per plant (108.69 ± 5.19 g) was achieved in T4, demonstrating the effectiveness of the 9:3:3 Azolla-ERP-PHA combination in enhancing chilli production. Comparatively, the control treatment (T1), with a 0:3:3 ratio of Azolla:ERP:PHA, exhibited significantly lower vegetative growth and yield parameters. Therefore, the 9:3:3 combination of Azolla, ERP, and PHA showed considerable potential for enhancing chilli growth and yield under pot conditions; however, field validation and multi-season testing are required before recommending it for commercial cultivation.
