Use rootstocks that are resistant to, or tolerant of, key disorders and diseases, such as Phytophthora root rot (Phytophthora cinnamomi). Because rootstock cultivars resistant to one problem may be more susceptible to another, consider planting a mixture of the recommended rootstock cultivars.
| ORIGIN | PATHOGENS1 | STRESSORS1 | ||||||
|---|---|---|---|---|---|---|---|---|
| Rootstock | Cultivar2 | Propagation | Phytophthora cinnamomi | Phytophthora mengei | Botryosphaeria spp | Salinity | Frost | |
| Barr Duke | Mex | clonal | 3.5 | 3 | 5 | 2 | 4.5 | |
| Borchard | Mex | clonal | 0.5 | 3 | 5 | 3 | 4.5 | |
| Duke 7 | Mex | clonal | 3 | 4 | 5 | 3 | 4 | |
| Duke 9 | Mex | clonal | 3.5 | 4 | 5 | 3 | 4.5 | |
| Dusa (Merensky 2) | Mex X G | clonal | 5 | — | 5 | 4 | 4.5 | |
| G-6 | Mex | seed | 2 | 3 | 2 | 2 | 4.5 | |
| Lula | G X WI | seed | — | — | — | — | 1 | |
| Latas (Merensky 1) | Mex X G | clonal | 4.5 | — | 5 | 5 | 4.5 | |
| Martin Grande | X3 | clonal | 5 | 3 | — | 2 | 1 | |
| Thomas | Mex | clonal | 4.5 | 2 | 2 | 1 | 4.5 | |
| Topa Topa | Mex | seed | 0 | 3 | 5 | 2 | 4.5 | |
| Toro Canyon | Mex | clonal | 2.5 | 5 | 5 | 3 | 4.5 | |
| Uzi (PP15) | Mex | clonal | 5 | 4 | 3 | 4 | — | |
| Zentmyer (PP4) | Mex | clonal | 5 | 3 | 4 | 1 | 5 | |
| 1 | Ratings for pathogen/stressor are from 0 to 5, with 0 being poor or least tolerant and 5 being the best or most tolerant. Ratings are approximate and based on observations and studies under a variety of field and greenhouse conditions. Ratings of newer rootstocks are preliminary; check with your advisor or supplier for the latest information on rootstock tolerances. |
| 2 | Cultivar or horticultural race is Mex = Mexican, G = Guatemalan, WI - West Indian, X = a hybrid of cultivars or species. |
| 3 | Martin Grande (also identified as G755 A,B,C) is a hybrid of Persea americana X P. schiedeana. |
| — | = unknown |
Adapted from: Bender, G., J. Menge, and M. L. Arpaia. 2003. Avocado Rootstocks. University of California Cooperative Extension. Topics in Subtropics 1(3): 7–8.