Symptoms
Only a few seeded berries set, most berries remain small and seedless. This is called millerandage, hen and chicken, or the pumpkin and pea symptom.
Reasons
Boron deficiency
Boron deficiency is one of the most serious nonparasitic grapevine diseases. It is observed especially on strongly acid soils (pH 3.5 - 4.5).
Grapevines: 1 to 1.5 l/ha at flower truss visible, at flower buds separated and at fruit set. Also, 1 to 2 l/ha after harvest before leaf senescence. Water rate: 200 to 1000 l/ha.
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