WINETECH Technical Yearbook 2021

TABLE 3. Berry mass, berries per bunch, bunch mass and yield of the 17 cultivars in 2020/21.

Among the red cultivars, Durif and Grenache noir produced the highest yields (table 3). In contrast, the yield of Malbec was disappointing. In the case of the white cultivars, Macabeo and Piquepoul blanc produced the highest yields, whereas the yields of Chardonnay and Verdelho were the lowest. It is interesting to note that berry mass did not significantly influence yield of the respective cultivars, but rather bunch mass, or the amount of berries per bunch. SUMMARY The soil preparation was done effectively to allow sufficient root development. Over the first three years, the water consumption increased as the canopies became larger. Due to the water-saving effect thereof, plastic mulches on the berms are essential for the establishment of dry-land vineyards. As the winter of 2020/21 was relatively wet, it will be important to determine how the cultivars will react if the winter rainfall is relatively low. The project will however run for another three years. This will present the opportunity to confirm whether the stronger vegetative growth

and higher yields of certain cultivars will be sustainable under the dryland conditions. Wine quality, another critical aspect, will also be considered. Realistic evaluation of the drought tolerance will only be able to take place after a few seasons. No recommendations can therefore be made at this stage. ACKNOWLEDGEMENTS Winetech for partial funding. The ARC for resources and infrastructure. Mr. H. Rossouw for permission to work on his farm, and for technical support. Vititec and Voor-Groenberg Nurseries for replacement vines. Colleagues at Nietvoorbij, in particular Mr. F. Baron, for their technical inputs.

Berry mass (g)

Berries per bunch

Bunch mass (g)

Yield (t/ha)

Cultivar

Arinarnoa

2.0 ab*

131 cd*

258 bcd*

6.3 cd* 11.0 ab

Durif

1.4 de

251 ab

348 bc

Grenache noir

2.0 a

298 a

594 a 129 e

13.0 a

Malbec

1.7 bc

66 d

2.5 e

Marselan Pinotage

1.1 e

160 cd 145 cd 180 bc 194 bc 136 cd 261 b 431 a 186 c 289 b 125 cd 105 d 76 d

184 de 205 de 299 bcd

5.5 cde 4.8 de 7.6 cd 8.1 bc 6.2 cd

1.4 cde

Shiraz

1.7 cd

Tempranillo

2.0 a

388 b

Touriga naçional

1.6 cd

217 cde

Assyrtico

2.6 a

269 c

5.0 c 1.7 d 8.5 b

Chardonnay Chenin blanc

1.3 cd 1.4 bc 1.4 bc

95 d

375 bc 621 a 304 c 442 b 135 d 314 c

Macabeo Marsanne

13.1 a

1.6 b

8.1 b

Piquepoul blanc

1.5 bc

11.8 a

Verdelho

1.1 d 2.7 a

2.9 d 7.3 c

For more information, contact Philip Myburgh at myburghp@arc.agric.za.

Vermintino

117 d

* Numbers followed by the same letters within a column do not differ significantly (p ≤ 0.05).

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