Seed dormancy in red rice. III. Response to nitrite, nitrate, and ammonium ions [Oryza sativa]

• Published in: Plant physiology (Bethesda) Vol. 73; no. 2; pp. 381 - 384
• Main Authors: COHN, M. A, BUTERA, D. L, HUGHES, J. A
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01-10-1983
• Subjects: After ripening; Agronomy. Soil science and plant productions; Biological and medical sciences; Dormancy; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Germination; Germination and dormancy; Nitrates; Nitrites; Plant physiology and development; Quaternary ammonium compounds; Rice; Seed dormancy; Seeds; Dormancy; Oryza sativa; Monocotyledones; Gramineae; Germination; Angiospermae; Spermatophyta; Inorganic element; Cereal crop
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.73.2.381

Sodium nitrite at 10 millimolar breaks dormancy of dehulled red rice (Oryza sativa). While germination is light independent, low pH conditions (pH 3) are required for maximum response. Water and buffer controls at pH 3 remain dormant. The response to nitrite occurs at 25 and 30°C but is reduced at 20°C, although nondormant seeds germinate readily at this temperature. The contact time for response to nitrite is less than 2 h at the start of imbibition. Seeds imbibed first in water show reduced germination when subsequently transferred to nitrite. Dehulled seeds show little or no response to nitrate and ammonium ions. Intact seeds remain dormant in the presence of nitrite or nitrate unless partially dry-afterripened. The pH dependence of nitrite sensitivity is reduced in intact, afterripening seeds. In highly dormant seeds, vacuum infiltration experiments suggest that the hull restricts uptake of nitrite.