18. Molybdenum deficiency
The native reserves of molybdenum in many New Zealand soils are very low13. Although extensive planting’s of kiwifruit have been made on soils on which responses to molybdenum by pasture plants have been recorded13, deficiencies have not been ... [... more]
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Introduction
Deficiency and toxicity symptoms of key elements are clearly illustrated and discussed in this publication. Comparisons are drawn between disorders to assist diagnoses, and background information on fertiliser recommendations and nutrient status ... [... more]
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FERTILISER
Disorders producing symptoms mainly on the older leaves - Zinc deficiency For many plant species, zinc is usually considered to be an element with very limited mobility in the phloem47. Any interruption in the external supply of zinc will cause ... [... more]
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Appendices
Factors for converting MAF Quicktest results to other units13. (1) Soil: extractant ratio 4.4:20 (v/v) for Ca, K, Mg, 1:20 (v/v) for P. (2) Approximate conversion for Ca, K, Mg and P based on a constant bulk density of 0.91 g/ml for prepared ... [... more]
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Diagnosis of nutritional disorders
Accurate diagnosis is essential if nutrient disorders are to be dealt with effectively. While this booklet is concerned mainly with mainly visual symptoms of nutrient deficiency and toxicity, confirmation of any diagnosis needs to be supported ... [... more]
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8. Salinity
Disorders producing symptoms mainly on the older leaves - Salinity Salinity is caused by high concentrations of salts in the soil solution. The chlorides and sulphates of sodium and magnesium are the most damaging of these salts to ... [... more]
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2. Magnesium deficiency
Early symptoms of magnesium deficiency include a pale yellow-green interveinal chlorosis of the older leaves on the current season’s extension canes. The chlorosis usually develops at the leaf margin and spreads inwards between the veins towards ... [... more]
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Glossary of terms
Soils containing large amounts of lime, usually calcium and magnesium carbonates. Green pigments located in the chloroplasts of the plant; responsible for the absorption of light energy which is essential for photosynthesis. Inorganic elements of ... [... more]
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List of references
Kiwifruit: A botanical review. Horticultural Reviews, 6, 1-64. . Copper deficiency in world crops. Outlook on Agriculture, 13, 31-34. . Programmed nutrient addition - a simple method for controlling nutrient status of plants. Working papers of ... [... more]
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SOURCE OF SUPPLY
The appearance of small irregular patches of yellow tissue near the centre of the younger leaves is the first sign of boron deficiency (Photo 16a). These patches enlarge and coalesce to form an extensive area of yellow tissue on both sides of the ... [... more]
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11. Phosphorus toxicity
Kiwifruit are relatively tolerant of excess phosphorus in the soil. To date phosphorus toxicity has not been observed in the field despite the very high phosphorus status of some New Zealand soils. For example, vines have been grown in soils with ... [... more]
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15. Sulphur deficiency
Sulphur deficiency causes some visible symptoms which resemble those of nitrogen deficiency. These include a severe reduction in growth and the development of pale-green to yellow leaves. An important point of difference, however, is that the ... [... more]
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