At Westfalia Fruit, research to develop disease-tolerant clonal rootstocks has been ongoing for more than 35 years. The objective is to produce uniform trees with superior tree health and yields. Success in this regard has been achieved by the development of the avocado rootstocks Latas® (Merensky 1), Dusa® (Merensky 2), Leola™ (Merensky 6) and Zerala™ (Merensky 5).
Latas® and Dusa® were successfully developed and tested over decades, and have enjoyed increasing success with the support of loyal licensees, specifically Brokaw Nursery from Ventura, California, and its affiliates across the Spanish-speaking world. These rootstocks have shown superior performance against Phytophthora cinnamomi root rot and in the case of Dusa®, also a fair amount of salinity tolerance. Dusa® has also attracted international attention as Hass yields have proven to be substantially increased when using this clonal rootstock.
To date the commercial performance of Westfalia’s Dusa® rootstock has been unparalleled, with Dusa® being the top seller among vegetatively propagated rootstocks worldwide in recent years (vegetative propagation is also known as ‘cloning’ or ‘clonal propagation’). Protected under Plant Breeders’ Rights and US plant patent, it is grown successfully in Australia, New Zealand, Spain, Israel, the USA, South America and South Africa. More than 1.5 million Dusa® trees are sold annually in the commercial market.
Introduced in 2020, Leola™ and Zerala™ yield healthier trees and better-producing orchards under challenging growing conditions than do other industry-standard rootstocks, as confirmed in recent trials. The rootstocks have been released in the USA and South Africa, with commercial roll-out to be expanded as further trials deliver similarly positive results. For more information on rootstock performance, contact the R&D team at Westfalia.
Merensky 5 and 6 are co-owned by Westfalia and the South African Avocado Growers’ Association (SAAGA).
The breeding and selection of new rootstocks is a long-term commitment, aiming at significantly outperforming current standard rootstocks in terms of productivity and / or increased root rot and salinity tolerance.
South African growers can contact their preferred Avocado Nurserymen’s Association (ANA) accredited nursery directly to enquire about the commercial availability of these rootstocks.
Growers outside South Africa are welcome to contact the IP management team to enquire about plant material availability in their country of origin.