Avocado Rootstocks

Definition and Types 


The rootstock is the foundation of the tree on which the graft is done and it provides certain desirable characteristics such as vigor, tolerance to salt, limestone, and soil fungi, while the scion is the commercial fruit variety..

There are two types of rootstocks:

We must pay attention to soil and climatic conditions of our farm before choosing the rootstock, so a preliminary study of water, soil and climatic conditions is recommended.

The importance of clonal avocados


Producción de patrones clonales de aguacate
Orchards planted with genetically homogeneous trees provide higher fruit yields and greater effectiveness in pruning, fertigation, application of pesticides and harvesting. Besides that, you get a uniform tolerance against soil fungi when appropriate clonal rootstocks are chosen.

Avocado seeds have a high genetic variability, for instance two seeds from the same tree do not have the same genotype, therefore they behave differently in the field. Hence the fruit scion grafted on these seedlings will behave differently. Avocado growers do not want to have variability in their orchards because that means different tree sizes, some yellow trees, others with low productivity and no tolerance to adverse soil characteristics such as salinity (burned leaves tips), high levels of carbonates (yellow trees), soil-borne fungi (root rot and dead trees) ...

To farm homogeneous avocado orchards, it is necessary to plant genetically identical trees produced by clonal propagation techniques.

Characteristics of Avocado Rootstocks



Clonal Avocado Rootstocks
D-7 Toro Canyon Dusa Borchard
Productivity in normal soil 4 3 4 4
Productivity in poorly ventilated soil 3 3,5 4 2
Tree size in normal soil 5 4 5 5
Tree size in poorly ventilated soil 2 3 4 0,5
Tolerance to Phytophthora Cinnamomi 3 3,5 5 0,5
Tolerance to Phytophthora Citrícola 4 5 ? 3
Salt tolerance 3 3,5 4 4,5
Tolerance to Lime-Induced Chlorisis 4 3 ? 5
Frost Tolerance 4 4,5 4,5 4,5
Horticultural Race Mexican Mexican Mex X Guat Mexican
Parentage Duke Escape Seedling Escape Seedling Escape Seedling
Geographic Origin Riverside, California Carpinteria, California Sudafrica Oxnard, California
Measured on a scale of values: 0 = Poor, 5 = Best

Seedling Avocado Rootstocks
Walter Hole G-6 Topa Topa
Productivity in normal soil 3,5 3 3
Productivity in poorly ventilated soil 1 2,5 1
Tree size in normal soil 4 5 5
Tree size in poorly ventilated soil 0,5 1 0,5
Tolerance to Phytophthora Cinnamomi 0 2 0
Tolerance to Phytophthora citricola 3 3 3
Salt tolerance 2 2 2
Tolerance to Lime-Induced Chlorisis 2 2 2
Frost Tolerance 4,5 4,5 4,5
Horticultural Race Mexican Mexican Mexican
Geographic Origin México Guatemala México
Measured on a scale of values: 0 = Poor, 5 = Best

How do I get genetically identical trees? 


The technique to get genetically identical avocado trees is the clonal propagation.

BROKAW ESPAÑA, S.L. has always been concerned to obtain the best avocado varieties for both, fruit scion and rootstock. Thanks to BROKAW NURSERY LLC California (USA) and its relations with public and private institutions, as well as other nurseries at international level, we can proudly say that we have available to Spanish growers the best avocado rootstocks in the world.

In the 50s Edward F. Frolich identified the etiolation technique (shoot growth in darkness, without chlorophyll) as the precursor to develop functional roots on shoots of avocado. The nurseryman W. Hank Brokaw was the first one to describe and develop the etiolation technique at commercial level. Over the years Brokaw Nursery has further refined the technique to reduce costs and improve the quality of the trees obtained by this technique.

With this technique avocado rootstocks with desirable traits can be propagated obtaining genetically identical avocado trees.

BROKAW ESPAÑA, S.L.
Fincas de Cabrillas y Las Alberquillas
Apartado de correos nº 87
29700 Vélez-Málaga. Málaga.
SPAIN

Sales contact mobile: 00 34 629543355 ( Antonio Guirado )
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Fax: 00 34 952 500980
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