Location: Plant Genetic Resources Unit (PGRU)Title: Effects of apple (Malus x domestica) rootstocks on scion performance and hormone concentration
|Lordan, Jaume - Cornell University - New York|
|Francescatto, Poliana - Cornell University - New York|
|Robinson, Terence - Cornell University - New York|
Submitted to: Scientia Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/13/2017
Publication Date: 7/11/2017
Citation: Lordan, J., Fazio, G., Francescatto, P., Robinson, T. 2017. Effects of apple (Malus x domestica) rootstocks on scion performance and hormone concentration. Scientia Horticulturae. 225:96-105.
Interpretive Summary: This manuscript describes the results of a 7 year old field trial of 10 apple rootstocks grafted with the apple variety Honeycrisp. We monitored yield components such as apples produced by each tree, tree growth and the weight of apples. In the last year we monitored natural endogenous plant hormones and found several correlations between hormones and field traits. This research will help identify which rootstocks are better suited for maintaining productivity in climate adverse conditions like drought or low chilling induction.
Technical Abstract: Rootstocks can influence the productivity and profitability of an orchard in a very significant way. Dwarfing rootstocks had a large impact in making possible the high-density orchards that have been planted during the last 15 years. However, there is a serious threat to high-density apple orchards, since many of them are planted on dwarfing rootstocks that are highly susceptible to the bacterial disease fire blight (Erwinia amylovora Burill). Nevertheless, new apple rootstocks that are fire blight resistant are rapidly becoming available in recent years. Rootstock effect on vigor, yield, return bloom, branch angle, bud break, and hormone profile was assessed using ‘Honeycrisp’ as the scion cultivar. Three Budagovsky (B.9, B.10 and B.7-20-20), five Geneva (G.814, G.214, G.935, G.41 and G.11) and two Malling (M.9T337 and M.26) rootstocks were used for this trial. G.814 and G.214 were high productive rootstocks, more vigorous than M.9T337 that could be interesting for weak growing cultivars such as ‘Honeycrisp’. B.9. B.10, G.41 and G.214 performed pretty similar to M.9T337, but they had slightly higher cumulative yields. G.814, G.935 and G.11 had a very uniform bud break, which indicates that these rootstocks could be suitable to test in areas where irregular bud break might be a problem. The high levels of endogenous ABA observed in Honeycrisp grafted on B.9 and G.11 suggests the possibility of these rootstocks tolerating drought stress by slowing evapotranspiration of the scion.