Abstract

This study was conducted to evaluate the interaction between rootstock type and scion cultivar on total nitrogen (N) concentration in the leaf of grafted apple scion at Chencha district of GamoGofa zone, Toloa site. For this purpose rootstocks MM.104, MM.111, MM.106, and M.26 were planted in a completely randomized design with three replications under naturally acidic soil (pH 4.8) condition. After two months of growth the rootstocks were grafted with scion of apple cultivars Crispin, BR, Granny Smith, Jonica and Royal Gala. After six months of growth, total N concentration in the leaf of scions was analyzed. Results showed that rootstock type had significant influence on total N concentration in leaf of apple scion. Highest (2.48 mg kg-1) and the lowest (1.71 mg kg-1) total N concentration were recorded on MM.106 and M.26 rootstocks, respectively. There was also significant difference in leaf total N between scions. Arrangement of scions from highest to lowest of total N concentration in leaf was Crispin (2.35 mg kg-1), Granny Smith (2.13 mg kg-1), Jonica (1.96 mg kg-1), Royal Gala (1.86 mg kg-1), and BR (1.74 mg kg-1). The result showed that the concentration of N in leaves of Crispin and Granny Smith were within the adequate range (2.00-2.25 mg kg-1), while Jonica, Royal Gala, and BR was below the range. In evaluate of rootstock and scion interaction distinguished rootstock type and scion cultivar have influence on leaf total N concentration.

Key words: Apple, rootstocks, scion cultivar, total N concentration.