Handbook for Irrigation of Wine Grapes in South Africa

Soil water content (mm/20 cm)

30

40

50

0

10

20

30

40

50 Depth (cm)

60

DMP = 1.5 t/ha DMP = 2.5 t/ha DMP = 5.2 t/ha

70

80

FIGURE 7.37. Effect of Triticale cover crop vigour as quantified in terms of DMP on soil water content at budbreak in the work row of a dryland Pinotage vineyard near Stellenbosch during the 2016/17 season (Moffat, 2017). Figure 7.38

A

B

Soil water content (mm/30 cm)

Soil water content (mm/30 cm)

0

50

100

150

0

50

100

150

0

0

10

10

20

20

30

30

40

40

50

50

Depth (cm)

Depth (cm)

60

60

70

70

No cover crop Cover crop killed at budbreak Growing cover crop

No cover crop Cover crop killed at budbreak Growing cover crop

80

80

90

90

FIGURE 7.38. Effect of a growing Triticale cover crop on soil water content at budbreak (A) in the grapevine row and (B) in the work row of a low frequency drip irrigated Cabernet Sauvignon vineyard near Philadelphia during the 2016/17 season. The DMP of the Triticale amounted to 5.1 t/ha (unpublished data).

224 CHAPTER 7 – IRRIGATION STRATEGIES