Occurrence, diagnosis, and correction of zinc deficiency of lowland rice

Abstract

Abstract Zinc deficiency occurs widely in lowland rice in Asia. The incidence of zinc deficiency is correlated positively with high pH, low available zinc content, and high organic matter in the soil. The problem fields often have poor drainage. An example of zinc deficiency was recorded for a “normal field” that had been cropped continuously. Visible symptoms and plant analyses were used as diagnostic techniques. The application of zinc sulfate, zinc chloride, zinc oxide, and FTE to the soil, and dipping roots of seedlings in 1 or 2% zinc oxide suspension were quite effective. Merits and shortcomings of these methods are discussed.