The avocados with rootstocks coming from seed have a high genetic variability. This feature determines that each tree has a different behavior. Until the eighties, in our nursery we developed only plants with imported selections seed such as Lula, Mexicola and Topa-topa.

Later we realized that to get country seats with homogeneous trees in terms of size and production and also trees tolerant to fungi, we had to use clonal rootstocks selected for this purpose. So from 1983 we started making clonal plant of Duke-7 and G-6 rootstocks (both Drymifolia Mexican breed) because these are tolerant to Phytophthora cinnamomi as well as highly productive. These two rootstocks were selected by Dr. George A. Zentmyer, from University of California. Also we did a 11 hectares plantation to check the effectiveness of them.