Symptômes
Young leaves are blueish green, the older ones show chlorotic tips and margins, followed by necrosis.
Raisons
Potassium deficiency
Symptômes
Leaves are blueish green with chlorotic tips and margins. Growth is reduced due to shortened internodes as deficiency becomes more severe.
Raisons
Potassium deficiency
Mild damage from herbicides may give similar symptoms.
Symptômes
Yellow-white streaking of leaves is one of several possible symptoms of K deficiency. Normally Potassium deficiency results in a characteristic pattern of leaf discoloration by small whitish-yellow spots, followed by scorching or browning of the leaf edge of lower, older leaves.
Raisons
Potassium deficiency
Symptômes
Leaves with P deficiency are smaller than normal and show purple tints on their dark green leaves, especially on the middle of the leaf blade.
K deficient leaves are even more stunted and their tips are scorched.
Raisons
P and K deficiency vs. optimum supply
Spring cereals may show reddening/purpling of older leaves in cold weather. Root and stem damage or poor soil consolidation can cause similar symptoms, too.
Symptômes
Scorching or browning of the leaf tip and edge of older leaves is characteristic for K deficiency. Starting from the leaf tip, the bottom leaves desiccate prematurely.
Leaf color in the present case is rather yellowgreen than bluish.
Total leaf and plant size are severely reduced.
Raisons
Potassium deficiency
Symptômes
Potassium deficiency results in a characteristic pattern of leaf discoloration by small whitish-yellow spots, followed by scorching or browning of the leaf edge of lower, older leaves. Intercostal chlorosis occurs toward the leaf base.
Young leaves show a blue tint.
Raisons
Potassium deficiency
Cereals: 5 l/ha from early tillering to 2nd node detectable (Zadoks G.S. 21 to 32). Repeat at 10 to 14 day intervals between these growth stages as necessary. From 2nd node detectable onwards apply 5 l/ha, if necessary, up to the end of inflorescence (Zadoks G.S. 32 to 59). Water rate: 50 to 200 l/ha.
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