Cocopeat: An alternative to soil medium for propagation of papaya (Carica papaya L)

The present study aimed to standardize soilless media mixtures for papaya propagation, focusing on stability, sustainability and environmental impact. A trial was conducted in the winter and summer seasons during 2023-2024 at TNAU, Coimbatore, to evaluate the properties of cocopeat mixtures and optimize the cocopeat media mixture for papaya seedling production. The trial employed a factorial randomized complete block design with two factors [cocopeat media mixture (Factor-T) and papaya varieties (CO7 and TNAU Papaya CO8, as factor-V] and with four replicates. Each treatment contains different proportions of cocopeat, inorganic fertilizers, bio-inoculants, biofertilizers and oil cakes. Commercially available cocopeat and potting mixture were used as absolute control and control, respectively. The findings showed that T2 (TNAU Mixture 2) consist of cocopeat (96.86%) + inorganic mixture (0.34%) + bioinoculant mixture (0.70%) + biofertilizer mixture (0.42%) + oil cakes mixture (0.42%) recorded increased seed vigour (96.86%), seedling survival (96.17%), seedling height (46.07 cm), leaf area/plant (28.50 cm2), leaf chlorophyll (26.05 SPAD units) and total nutrient (N-1.89%, P-0.89%, K-3.47%). The treatment T4 (commercially available cocopeat alone) had the highest germination (97.90%) and was on par with T2. Among the variety, V2 outperformed V1. In the treatment (T) and variety (V) interaction, the T2xV2 combination promoted significant seedling growth at the nursery. Cocopeat media mixtures showed good physical properties, like bulk density(g/cc), particle density (g/cc), porosity (%) and water holding capacity (%), promoting better seedling growth. The trial revealed that the treatment T2 is recommended as the best alternative soilless medium for papaya propagation.