Potassium Supply Influences Molybdenum, Nitrate, and Nitrate Reductase Activity in Eggplant

• Published in: Journal of plant nutrition Vol. 26; no. 3; pp. 659 - 669
• Main Authors: Víllora, Gemma, Moreno, Diego A, Romero, Luis
• Format: Journal Article
• Language: English
• Published: Philadelphia, NJ Dekker 01.03.2003; Taylor & Francis Group; Taylor & Francis
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Economic plant physiology; eggplants; Fruit; fruit quality; fruits; Fundamental and applied biological sciences. Psychology; greenhouse experimentation; greenhouses; humans; Leaf; Mediterranean climate; Metabolism; Metabolism. Physicochemical requirements; molybdenum; nitrate reductase; nitrates; Nitrogen; Nutrition. Photosynthesis. Respiration. Metabolism; petioles; Plant physiology and development; potassium; potassium sulfate; Solanum melongena; Solanum melongena; Enzyme; Supply; Activity; PLANT NUTRITION; Molybdenum; Nitrate reductase; Dicotyledones; Angiospermae; Spermatophyta; Oxidoreductases; Solanaceae; Potassium
• ISSN: 0190-4167; 1532-4087
• DOI: 10.1081/PLN-120017672

Greenhouse experiments were conducted for two years (1993-1994) with eggplants to study the impact of potassium (K) as K2SO4 (0.5 mM, 1 mM, 2 mM, and 3 mM) on molybdenum (Mo) distribution and on aspects of nitrate (NO3 -) metabolism, and fruit quality. The nitrates and Mo in leaf blades, petioles, and fruits as well as foliar in vivo nitrate reductase (NR; E.C. 1.6.6.1) activity were analyzed. In view of these results, the K application at levels exceeding 0.5 mM K, altered the NO3 - and Mo status and distribution in the aboveground organs of eggplant. The 3 mM K distributed the NO3 - proportionally between leaf blades, petioles, and fruits. The 0.5 mM K and the 1 mM K increased the NO3 - and Mo concentration in fruits, respectively. These results indicated the 3 mM K the most appropriate treatment for the greenhouse eggplant production under Mediterranean climate conditions, with reduced NO3 - density in fruits for human consumption.