Enhancing the success rate of semi-micrografted mandarin orange (Citrus reticulata), variegated chinotto sour orange (Citrus myrtifolia foliis variegates) and sour orange (Citrus aurantium L.) while reducing incidences of the Tristeza Virus and Fusarium oxysporum in grafted plants

The primary vitamin C source in our diet comes from citrus fruits. It is rich in antioxidants and anti-inflammatory properties, which are vital to disease prevention. Widely grown worldwide, citrus fruits are valued for their medicinal and economic benefits. Grafting is the commonly used method for propagating citrus, as seed propagation results in diverse progenies. Therefore, to maintain the true-to-type characters of the mother plant, it is propagated clonally through bud-grafting. However, one drawback of grafting is the potential transmission of diseases. To address this, an in-vitro micrografting technique was developed to prevent disease transmission during plant propagation. However, this technique requires modification due to its high cost, demand for skilled labour, and long propagation time. This study introduced a cost-effective, labour-efficient, and timesaving-enhanced semi-micrografting technique. Various treatments were evaluated based on graft success percentage, and the results were analysed using a one-way analysis of variance and Tukey’s honestly significant difference test. The results revealed that the combination of 10 mg \({\mathbf{L}}^{-1}\) ${\mathbf{L}}^{-1}$ gibberellic acid, 10 mg \({\text{L}}^{-1}\) ${\text{L}}^{-1}$ 2,4–dichlorophenoxyacetic acid, 500 mg \({\text{L}}^{-1}\) ${\text{L}}^{-1}$ ascorbic acid, 50 mM calcium chloride and 30 μL of Ceylon cinnamon leaf oil was the best treatment, as it had the highest grafting success rate (62.22 ± 5.091%) compared to the other treatments. The study demonstrated that the enhanced semi-micrografting technique could significantly decrease the incidence of Citrus tristeza virus and Fusarium oxysporum diseases in grafted sour orange, mandarin orange, and variegated Chinotto sour orange plants, achieving disease reductions of 96% and 86%, respectively while maintaining a high graft success rate.