Performance of Hass on Clonal Dusa^®

Rigorous Testing

All rootstocks commercialised by Westfalia undergo  repeated testing in various geographic areas before being released.

Proven Benefits 

• Short term—tree health,  precocious yield

• Long term— less use of chemicals for Phytophthora control, improved yield.

Tree Health

Hass on Dusa^® (left) vs Hass on Duke 7 (right)   (the previous standard rootstock in the South African avocado industry). Trees were four years old and had not received any Phytophthora treatments yet.

Advantages of Clonal Dusa^®

From research trials and commercial plantings of avocados on clonal Dusa® rootstocks, both in California and in South Africa, the following characteristics have been established:

• Precocious bearing of Hass on Dusa^®, often at least a year earlier than on other rootstocks.
• A yield increase of 20 to 40% of Hass on Dusa^® when compared to Hass on Duke 7, the standard clonal rootstock used.  These first two points contribute to the financial break-even point being achieved a year or two earlier than other rootstocks.
• Higher tolerance than Duke 7 to Phytophthora root rot and all seedling rootstocks used in South Africa.  This has been confirmed in many trials in South Africa, California and recently Australia.  In effect, the onset of Phytophthora injections has been delayed by 1 to 3 years depending on the root rot pressure, and the number of injections per year has also decreased. 
• A tolerance to salinity in both soil and water has been found with Dusa^® in California.

Figure 1. Yield comparison of ‘Hass’ grown on Dusa®/Merensky 2, in different geographic areas (showing planting date), vs other commercially available South African rootstocks such as Duke 7 and Latas®/Merensky 1. Figures above bars indicate yield advantage based on cumulative yield.