Agronomic and Physiological Responses of Sweet Potato to Moringa Leaf–seaweed Liquid Organic Fertilizer in Coastal Soil

Abstract

Aims: To determine the physiological and agronomic responses of sweet potato plants to the application of liquid organic fertiliser (LOF) prepared from moringa leaves and seaweed, and to identify the best moringa leaf-seaweed LOF combination for sweet potato growth and yield in coastal soil. Study Design: Completely randomised block design. Place and Duration of Study: The research was conducted over two growing seasons, from August to November 2022 and from January to April 2023, on coastal land in Bengkulu Tengah, Indonesia. Methodology: Two consecutive field experiments were conducted in 2022 and 2023. The treatments were LOF1 = 100% flowering moringa leaves, LOF2 = 100% non-flowering moringa leaves, LOF3 = 100% seaweed, LOF4 = 50% seaweed + 50% flowering moringa leaves, LOF5 = 50% seaweed + 50% non-flowering moringa leaves, and LOF6 = 50% seaweed + 25% flowering moringa leaves + 25% non-flowering moringa leaves. Results: Pooled data from the two-year experiments indicated that LOF prepared from 100% flowering moringa leaves was more effective in increasing chlorophyll a and carotenoid contents, whereas LOF prepared from 50% seaweed + 50% non-flowering moringa leaves was more effective in increasing proline content. However, the treatments did not affect chlorophyll b, total chlorophyll, tuber sweetness, nitrogen uptake, phosphorus uptake, potassium uptake, leaf greenness, fresh plant weight, dry plant weight, number of tubers per plant, or tuber weight per plot. Conclusion: The results suggest that moringa leaf- and seaweed-based LOF can influence selected physiological responses of sweet potato grown in coastal soil, although its effect on agronomic yield was not significant under the conditions of this study.