Effects of Rootstock Type and Scion Cultivar on Grafting Success and Growth of Mango (Mangifera indica L.) Seedlings

Aim: To evaluate the effects of three types of rootstocks: (i) Ngwangwa (ii) Sindano and (iii) Zinzi commonly used in the coastal belt of Tanzania on grafting success and seedling growth of six improved mango cultivars: (i) Apple (ii) Ngowe (iii) Kent (iv) Keitt (v) Alphonso and (vi) Tommy Atkins.

Study Design: Plants were arranged in a split plot design with three replications. The rootstocks were main plots while the scion cultivars were subplots.

Place and Duration of Study: At Chambezi research farm of Mikocheni Agricultural research institute (MARI) located at 6°30’S and 38°55’E at altitude of 12 meters above sea level in the coastal belt of Tanzania, from January 2014 to March 2015.

Methodology: Seedlings were raised in polyethylene bags. Data on germination, plant height, root collar diameter (RCD), number of leaves, leaf length, leaf width before and after grafting were recorded at one month interval.

Results: Ngwangwa rootstock had the highest seed germination percentage (92.7%) followed by Zizi (69%) and the lowest Sindano (17.4%). The number of leaves was also maximum for Ngwangwa (21) followed by Sindano (16) and Zizi (13). The highest graft success with all tested scion cultivars was in the order of Ngwangwa (100%), Zizi (60%), and Sindano (52.5%). The interactions between the rootstocks and scion cultivars was significant (P ≤ 0.01) for leaf area, plant height, and RCD indicating that seedlings growth after grafting is influenced by type of rootstock and scion cultivar used.

Conclusion: Ngwangwa rootstock had the highest number of leaves, leaf size, graft take and compatibility among all the tested cultivars therefore considered a potential rootstock for grafting improved mango seedlings. However, high grafting success at the nursery stage does not always lead high scion growth. Therefore, a follow up field study to confirm the success of this rootstock is recommended prior to wider adoption by mango growers.