Effect of several kinds of potting media on tuberous yield and quality of eddoe taro plants (Colocasia esculenta L.) in various potting substrates

Eddoe taro (Colocasia esculenta (L.) Schott var. antiquorum) is a valuable tuber crop widely cultivated for its starchy corms and cormels, which serve as a rich source of carbohydrates and essential nutrients. However, the optimization of potting media for eddoe taro cultivation in controlled environments has not been fully explored. This study evaluated the effects of five potting substrates on the growth, tuber yield and quality of eddoe taro under nethouse conditions. A completely randomized design was employed with five treatments: Loamy soil (Tre 1), loamy soil + coconut coir (1:1) (Tre 2), loamy soil + TMX mixed soil (1:1) (Tre 3), loamy soil + coconut coir + TMX mixed soil (1:1:1) (Tre 4) and loamy soil + mixed coconut coir (rice husk: rice husk ash: coconut coir, 1:1:5) + TMX mixed soil (1:1:1) (Tre 5). Each treatment consisted of 15 replicates (one plant per pot). Growth parameters such as plant height, leaf number and leaf size were significantly improved in treatments containing TMX mixed soil (Tre 3, 4 and 5) compared to treatments without TMX (Tre 1 and 2). Tre 4 yielded the highest total cormels (37 per plant), marketable tubers (20.5 per plant), corm yield (0.95 kg/m²), cormel yield (8.81 kg/m²) and marketable yield (8.29 kg/m²). Additionally, this treatment produced tubers with superior quality characteristics, including 15.4 % dry matter content and 27.9 mg/g fresh weight of total sugar. These findings demonstrate that loamy soil combined with coconut coir and TMX mixed soil (1:1:1) serves as an optimal substrate for eddoe taro cultivation in pots under controlled environments, offering practical solutions for urban and small-scale farming systems.