10. Nitrogen excess
Excess nitrogen readily reduces the growth of kiwifruit (Photo 10a). Symptoms appear first on the older leaves as an interveinal scorching which spreads from the leaf margins towards the midrib (Photo 10b). Leaves on affected plants are very much ... [... more]
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7. Boron toxicity
Disorders producing symptoms mainly on the older leaves - Boron toxicity Early symptoms of boron toxicity include a yellow-green interveinal chlorosis developing first on the older leaves and spreading progressively to the younger leaves (Photos ... [... more]
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Nutritional effects on fruit yield
Nutritional effects on fruit yield and Quantitive nutrient requirements of kiwifruit. Extensive surveys of the major kiwifruit growing areas of New Zealand have shown that nutritional disorders can result in serious losses of fruit production and ... [... more]
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Contact and residual herbicides
Symptoms associated with non-nutritional disorders - Herbicides Glyphosate injury to young kiwifruit plants results in elongated and distorted leaves (Photos 23a and 23b). Frequently the tissue between the minor veins is ridged upwards and in ... [... more]
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6. Chlorine (Chloride) deficiency
Disorders producing symptoms mainly on the older leaves - Chlorine (Chloride) deficiency One of the most extraordinary features of the nutrition of kiwifruit is their high requirement for chlorine (chlorine is always present in plant tissues as ... [... more]
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14. Iron deficiency
Iron deficiency can be distinguished from other nutritional disorders by the development of a characteristic interveinal chlorosis of the younger leaves grading from yellow through to snow white (Photo 14a). The older leaves often remain green ... [... more]
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5. Phosphorus deficiency
Phosphorus deficiency can reduce the growth of kiwifruit without the development of obvious visible symptoms (Photo 5a). the stems of affected plants tend to be much thinner and the size of the leaves considerably reduced. Clearly recognisable ... [... more]
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1. Potassium deficiency
Disorders producing symptoms mainly on the older leaves - Potassium deficiency The first sign of potassium deficiency in the field is poor growth at bud break. On severely affected vines the leaves are small and pale yellow-green with a slight ... [... more]
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Symptoms associated with non-nutritional disorders
Symptoms associated with non-nutritional disorders - Drought stress, Bacterial leaf spot, Low temperature. Kiwifruit require a well distributed rainfall and high humidity36. A recent estimate of the amount of water transpired by mature kiwifruit ... [... more]
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13. Calcium deficiency
Symptoms of severe calcium deficiency develop first on recently matured leaves (Photo 13a) and spread to progressively younger leaves. Initially, the veins at the base of the leaf become necrotic and turn black (Photo 13b). As the deficiency ... [... more]
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19. Zinc toxicity
Zinc toxicity is characterised by a severe reduction in dry matter yield. Both internode elongation of the stem and leaf expansion are retarded. Symptoms appear first on the young immature leaves as a pale green chlorosis (Photo 19a). A marginal ... [... more]
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12. Manganese deficiency
Manganese deficiency produces a light green to yellow interveinal chlorosis which appears first on recently matured leaves, but in severe cases it may affect almost all leaves on a plant (Photo 12a). The chlorosis develops initially at the leaf ... [... more]
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