Field performance of peach rootstock cultivars in South Carolina

Three peach rootstock trials were established in South Carolina between 2013 and 2017 to evaluate new rootstock cultivars for yield, resistance to Peach Tree Short Life (e.g., bacterial canker), Armillaria root rot tolerance, and tree vigor.
In a high density, Y-trained 2017 trial, ‘Rootpac^® 40′, ‘Controller™ 7′, ‘Controller™ 8′ and ‘MP-29′ produced the smallest trees after 5 years – 38 to 48% of Guardian^®. ‘Rootpac^® 20′ produced the most root suckers.
Bloom and maturity dates were advanced 2 to 3 days on ‘Rootpac^® 20′, ‘Rootpac^® 40′, and Guardian^® compared to Lovell.
However, an adjacent open center, 2013 trial there were few differences in phenology among rootstocks except ‘MP-29′ advanced maturity.
Yields in the Y-trial were highest for the vigorous rootstocks Lovell and Guardian^® as well as ‘Rootpac^® 20′. In comparison in the 2013 trial, yields were highest for peach seedling cultivars and ‘Rootpac^® R’. In the Y-trial, ‘Rootpac^® 40′ was 48% smaller than ‘Rootpac^® 20′, which was contrary to the release descriptions.
Similarly, ‘Controller™ 6′ was ~38% larger than ‘Controller™ 7′ and ‘8′, which was unexpected.
For the two other older trials, the cultivars ‘Rootpac^® 20′, ‘40′, ‘70′, ‘R’, and ‘Tempropac^®‘ had tree mortalities as high as 78-100% due to bacterial canker.
European interspecific hybrid rootstocks had fair to poor survival, in contrast to only a few dead trees on P. persica rootstocks. ‘MP-29′, considered a Peach Tree Short Life resistant rootstock, was resistant to Armillaria in a 9-year trial.
European rootstock cultivars were not well adapted.
Future research will focus on the semi-dwarfing and better adapted ‘MP-29′ and ‘Controller^®‘ rootstocks for intensive orchard systems.

X International Peach Symposium

G.L. Reighard, D. Ouellette, I.S. Minas

Prunus persica, Prunus hybrids, dwarfing, Peach Tree Short Life, Armillaria tabescens

https://doi.org/10.17660/ActaHortic.2022.1352.8