Plant selection, pre-harvest treatments and post-harvest management to prolong the vase-life of shoot cuttings of Codiaeum variegatum (croton)

Abstract

Condiaeum variegatum is easily grown under hot and humid field conditions and has a high export potential. However, wilting and senescence during post-harvest operations often reduces its vase-life. To improve this drawback, an investigation was conducted to preserve the export quality of C. variegatum vars. Mariana, Batik and Aucubeafolia. Eight separate experiments were conducted to maintain high quality standards during storage life of three varieties of C. variegatum. Cold treatment with or without hot water dip, leaf morphology, leaf maturity with cutting type, pre-harvest hormonal regulation, de-topping, post-harvest hormonal regulation, commodity treatments and combined treatments of the above were the test criteria. The vase-life of three Codiaeum varieties were significantly different from each other. Similarly their response to individual treatments was also variable. Some of these individual treatments such as hormonal regulation were not compatible to be used as a combined treatment. Selection of mature or partially mature stem cuttings having a full length of purple and elongated leaves, de-topping 1-2 weeks before harvesting, spraying of 0.1mM of Kinetine 4 days before harvesting, application of 100 ppm of Gibberellic acid (GA3) after harvesting, pre-cooling at 17°C and 79% humidity for one day (after harvesting) and application of commodity treatment of 2mg/L of KMnO4 with 2.5% of sugar and citric acid were the ideal individual treatments for extending the vase-life of Codiaeum varieties. Except post-harvest hormonal regulation, all the other plant selection criteria and post-harvest treatments that are mentioned above could be practiced in combination to increase the vaselife of all three varieties of Codiaeum without loosing the export standards significantly. The increased vase-life under combined treatment was18 days for var. Mariana, 20 days for var. Batick and 24 days for var. Aucubaefolia which was a 36.2% increase.