Five-year performance of 19 peach rootstocks at 20 sites in North America.

摘要

Nineteen Prunus persica rootstock cultivars and selections budded with Redhaven peach were planted at 20 locations in 17 states in USA and in Ontario, Canada in 1994 as an official planting of the NC-140 Cooperative Regional Rootstock Project. The rootstocks included peach seedlings from cultivars Lovell, Nemaguard, Bailey, Tennessee Natural 281-1, Stark's Redleaf, GF 305, Higama, Montclar, Rubira, Chui Lum Tao, Tzim Pee Tao, H7338013, H7338019, BY520-8 and Guardian BY520-9. Clonal rootstocks included Ishtara, Myran, S.2729, and Ta Tao 5 interstem on Lovell. Five-year data were summarized across the 20 sites in 18 states and provinces. Tree growth, measured as trunk cross-sectional area, was best in southern Illinois, central Tennessee, southeastern Missouri, eastern Maryland and central New Jersey, USA. Across all locations, no rootstock was more vigorous than Lovell or Nemaguard. However, within locations, some rootstocks produced larger trees than Lovell and/or Nemaguard. Full bloom date was delayed 1.0-1.5 days with Ta Tao 5 interstem. Fruit maturity was slightly earlier in Ishtara; whereas, it was delayed in Ta Tao 5. Rootstock genotype effect on bloom advancement and ripening delay in days was much longer in the South (i.e., Georgia, SouthCarolina). Highest cumulative fruit yields were from Maryland, New Jersey, Ohio and South Carolina. Few rootstocks yielded better than Lovell and these differences were not usually significant at most sites. The largest fruit were from Massachusetts, Illinois, Missouri, Ohio and Colorado. Relative fruit size was not affected by rootstock generally, except for Myran, which tended to have smaller fruits than Lovell. After 5 years, no rootstock consistently performed better than the standard, Lovell. Someperformance trends are developing and superior rootstocks may be identified in the future after additional data are collected during the next 5 years.