Exogenous application of paclobutrazol and TIS108 effectively increases shoot branching and mineral element utilization efficiency of ‘Duli’ (Pyrus betulifolia Bunge)

• PAC and TIS108 increase branch number, length, and photosynthesis and reduce plant length. • The content of N, P, Ca, and Mg was positively correlated with branch number, while GA 3 and SLs were negatively. • PAC and TIS108 regulate the expression of GA and SL pathway genes, and genes related to element absorption. • 10 μM PAC +0.1 μM TIS108 treatment was optimal for improving branching and mineral element utilization. Dwarfing and branching are important indexes affecting the yield of plants. However, the effect of paclobutrazol (PAC) and TIS108 on branching and the mineral element content is limited. Here, we studied the effects of PAC and TIS108 on the branching and nutrient utilization of ‘Duli.’ Each treatment significantly increased the number of branches and branch length and decreased the plant length. Each treatment significantly decreased the content of gibberellin (GA 3 ) and strigolactones (SLs) and promoted photosynthesis. Additionally, the content of GA 3 and SLs and the activities of D27, CCD7, and LBO were significantly negatively correlated with the number of branches. The membership function showed that plant length and the number of branches were highest in the 10 μM PAC + 0.1 μM TIS108 treatment. Furthermore, the concentrations, uptake, shift, and partitioning of ions varied among treatments. A mantal test showed that the N content was positively correlated with the number of branches. Principal component analysis was used to comprehensively evaluate the importance of 59 single indicators; the score that was correlated with the number of branches and mineral element content was highest for the 10 μM PAC + 0.1 μM TIS108 treatment. qRT-PCR showed that the expression level of genes (e.g., PbMAX and PbGA2ox ) in the SL and GA pathways in each treatment was decreased. Our findings show that PAC and TIS108 could help achieve the dwarfing and high-density cultivation of pear.