Efficacy of IBA (indole-3-butyric acid) and kinetin for the success of T-budding in citrus

The success of budding depends on the plant’s internal auxin and cytokinin levels; however, applying synthetic auxins externally, alone or in combination with cytokinins, substantially improves plant propagation. In the current study, the scions of kinnow mandarin were treated with 0, 30, and 60 mg/L IBA (indole-3-butyric acid) and 0 and 5 mg/L kinetin to evaluate their effects on the success of T-budding on rough lemon rootstock. The results of this study confirm that the quickest bud sprouting (29–32 days after budding) with the highest percentage of sprouts (72.5–75.0%), girth of the sprouted scion and rootstock, scion-to-stock ratio at 180 days after bud sprouting (DABS), shoots of the sprouted scion, shoots per plant, leaves per shoot, plant height, and the survival (98.5%) of budded plants was observed when 5 mg/L kinetin was used with 30–60 mg/L IBA. All variables, including bud sprouting percentage (BSP), have reflected significant and positive correlation with survival, except for days to bud sprouting (negative correlation) (DTBS) and number of leaves per shoot (non-significant correlation). Principal component analysis (PCA) confirms that the first two PCs (PC1 and PC2) explain the most variance (91%). Further, the loading of the correlation matrix on PC1 is positive for all parameters except DTBS (− 0.341), reflecting a significant effect of IBA and kinetin on the success of budding.