Impact of planting material types on success of infilling in Cinnamon (Cinnamomum zeylanicum Blume) cultivation

Abstract

Infilling is a crucial agronomic practice in cinnamon cultivation as it enhances yield. However, the success of infilling depends on choosing correct planting materials and proper after care practices. Therefore, a field experiment and a survey were conducted from May to August 2024 in Beliatta and Kamburupitiya, Matara, Sri Lanka, to select suitable planting materials for infilling and identify key management changes associated with the age of cinnamon cultivation. The field experiment was conducted using Randomized Complete Block Design (RCBD) with six treatments: normal polybagged plants, normal polybagged plants with tip pruning, normal poly bagged plants treated with gibberellic acid hormone (100 ppm), super grade polybagged plants (30 cm x 25 cm), super grade polybagged plants with tip pruning and super grade polybagged plants treated with gibberellic acid hormone (100 ppm), applied across six blocks representing different ages of cultivation (0-1, 1-2, 2-3, 3-4, 4-5 and more than 5 years old) cultivations. All treatments were randomly applied in vacant patches within each block with three replicates. Plant height was recorded weeklyA survey was conducted with 40 farmers. Survey results were presented using pie charts and bar graphs, while field experiment data were analysed using the non-parametric Friedman test. Results revealed that the success of infilling in cinnamon was significantly (p ≤ 0.05) dependent on both types of planting material and the age of cultivation. Tip pruning had a significantly positive effect (p ≤ 0.05) increasing plant height by 41% compared to other treatments. Although success rate was 100% in all treatments, both super grade and normal polybagged plants with pruning showed significantly higher growth after infilling in the fields. Furthermore, significantly (p ≤ 0.05) highest plant height increments were observed in 1 2 years (19%) and 4-5years (21.5%) after field establishment. Survey results indicated that infilling declined with the age of cultivation. All farmers practiced weed control and fertilization, but lack of pest control, pruning and training and peacock damage tended to reduce infilling success. Therefore, it can be concluded that both normal and super grade polybagged plants, when tip-pruned showed significantly higher post- infill growth compared to other treatments. The optimal periods for successful infilling in cinnamon cultivation appear to be between 1–2 and 4–5 years after field establishment.