Laitue - Necrosis
Symptômes
Symptoms of zinc deficiency on lettuce start on older or medium leaves. They develop papery, grey-green necrosic spots with brown borders on leaf margins. Necrotic areas increase quickly and flow together.
Leaf parts which are not subjected to light remain green.
Growth is restricted.
Zinc deficiency in an early stage of development causes rosetting, no heads are formed.
Raisons
Zinc deficiency on leaves compared to optimum supply
Laitue - Growth retardation
Symptômes
Symptoms of zinc deficiency on lettuce start on leaf margins of older or medium leaves. They develop papery, grey-green necrotic spots with brown borders, mostly without preceding chlorosis. Necrotic areas increase quickly and flow together.
Leaf parts which are not subjected to light, remain green.
Growth is restricted.
Zinc deficiency in an early stage of development causes rosetting, no heads are formed.
Raisons
Zinc deficiency
Laitue - Growth retardation
Symptômes
Symptoms of zinc deficiency on lettuce start on leaf margins of older or medium leaves. They develop papery, grey-green necrotic spots with brown borders, mostly without preceding chlorosis. Necrotic areas increase quickly and flow together.
Leaf parts which are not subjected to light, remain green.
Growth is restricted.
Zinc deficiency in an early stage of development causes rosetting, no heads are formed.
Raisons
Zinc deficiency
Laitue - Growth retardation
Symptômes
Symptoms of zinc deficiency on lettuce start on leaf margins of older or medium leaves. They develop papery, grey-green necrotic spots with brown borders, mostly without preceding chlorosis. Necrotic areas increase quickly and flow together.
Leaf parts which are not subjected to light, remain green.
Growth is restricted. Zinc deficiency in an early stage of development causes rosetting, no heads are formed.
Growth of roots is slightly restricted.
Raisons
Zinc deficiency on leaves and roots
Laitue - Chlorosis
Symptômes
Symptoms of zinc deficiency on lettuce start near leaf margins of older or medium leaves. They develop papery, grey-green necrotic spots with brown borders, mostly without preceding chlorosis. Necrotic areas increase quickly and flow together.
Leaf parts which are not subjected to light, remain green.
Raisons
Commencing zinc deficiency on leaves
Zinc deficiency vs. optimum aggravé par
- Organic soils
- High pH soils
- Soils rich in phosphorus
- Soils receiving high phosphorus application
- Cold wet conditions
Zinc est important pour
- Enzyme activation, but also for synthesis of growth regulators
