Technical Yearbook 2023

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0 5 0 5 0 5 10 15 20 25 30 35 40 45 10 15 20 25 30 35 40 45 10 15 20 25 30 35 40 45 10 15 20 15 20 25 20 25 30 25 30 10 15 30

Phosphorus extracted (kg/ha)

Nitrogen extracted (kg/ha)

4

Phosphorus extracted (kg/ha)

Nitrogen extracted (kg/ha)

0 1 0 1 2 1 2 3 2 3 4 3

FIGURE 2. The average amount of macro-elements extracted from the vineyard soil by the catch crops in May for three years.

Phosphorus extracted (kg/ha)

Nitrogen extracted (kg/ha)

accumulated the most N in their foliage. Given that Dolichos beans (T3 & T4) produced the highest DMP, it generally extracted the most elements from the soil with the exception of Na (figure 2). As expected, the N-fixing winter cover crop (T2, T4, T6 & T8) accumulated higher N in its foliage when compared to the oats, i.e. T1, T3, T5 and T7 (data not shown). The average K contents of the foliage of the oats and N-fixing winter cover crops were 2.25% and 2.94%, respectively. The average Ca contents of the foliage of the oats and N-fixing winter cover crops were 0.28% and 1.07%, respectively. The average Mg contents of the foliage of the oats and N-fixing winter cover crops were 0.11% and 0.29%, respectively. The average Na contents of the foliage of the oats and N-fixing winter cover crops were 1 133 mg/kg and 1 834 mg/kg, respectively.

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

0

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

30

Potassium extracted (kg/ha)

Calcium extracted (kg/ha)

10 15 20 15 20 25 20 25 30 25 30 10 15

Potassium extracted (kg/ha)

Calcium extracted (kg/ha)

Potassium extracted (kg/ha)

Calcium extracted (kg/ha)

5

5

0 5 10

0 5 10

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

0 5

0 5

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

0 1 1 2 1 2 3 2 3 4 3 4 5 4 5 5 0 0

0

Magnesium extracted (kg/ha) Pearl millet Dolichos beans Chicory

1,0

Sodium extracted (kg/ha) Pearl millet Dolichos beans Chicory

0,0 0,2 0,2 0,4 0,2 0,4 0,6 0,4 0,6 0,8 0,6 0,8 1,0 0,8 1,0 0,0

Sodium extracted (kg/ha)

Magnesium extracted (kg/ha)

Sodium extracted (kg/ha)

Magnesium extracted (kg/ha)

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

0,0

0

Pearl millet Dolichos beans Chicory

Pearl millet Dolichos beans Chicory

TABLE 1. The catch crop dry matter production (DMP) was determined for the treatments applied in the vineyard irrigated full surface in May for the duration of the study. Treatment no. Catch crop/cover crop combination DMP (t/ha) 2018 2019 2020 1 Pearl millet/Oats 0.00 0.30 0.22 2 Pearl millet/N-fixing mixture 0.00 0.29 0.37 3 Dolichos beans/Oats 0.52 1.07 1.59 4 Dolichos beans/N-fixing mixture 0.23 1.22 1.68 5 Chicory/Oats 0.00 0.17 0.00 6 Chicory/N-fixing mixture 0.00 0.06 0.00 LSD (p=0.05) 0.30 0.81 NS

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TECHNICAL YEARBOOK 2023