The effect of nitrogen concentration on nitrogen use efficiency and related parameters in cultivated rices (Oryza sativa L. subsp. indica and japonica and O. glaberrima Steud.) in hydroponics

• Published in: Euphytica Vol. 198; no. 1; pp. 137 - 151
• Main Authors: Nguyen, Hanh Thi Thuy, Van Pham, Cuong, Bertin, Pierre
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.07.2014; Springer; Springer Nature B.V
• Subjects: Agronomy; Agronomy. Soil science and plant productions; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Crop science; Cultivars; Cultivation; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Grain cultivation; Hydroponics; Life Sciences; Nitrogen; Physiological aspects; Plant Genetics and Genomics; Plant Pathology; Plant Physiology; Plant Sciences; Rice; Agronomical NUE (agNUE); Nitrogen use efficiency (NUE); Physiological NUE (pNUE); Steud; L; Absorption NUE (aNUE); Monocotyledones; Nutrient recovery; Oryza sativa L; Nitrogen; Cereal crop; Oryza glaberrima Steud; Oryza sativa; Absorption; Gramineae; Hydroponic cultivation; Angiospermae; Genetic improvement; Spermatophyta; Chemical concentration; Physiology
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/s10681-014-1101-9

Nitrogen use efficiency (NUE) in cultivated rice has become of utmost importance due to ecological and economical consequences of nitrogen (N) losses. However, detailed information on the components of NUE—physiological, absorption and agronomical NUEs—is lacking. The present study aimed to determine the components of NUE for three cultivars of Asian and African rices [IR64 ( Oryza sativa indica ), Azucena ( O. sativa japonica ) and TOG7105 ( O. glaberrima )] exposed to a wide range of N supply, from excess to deficiency—from 4× to 1/8× of the standard Yoshida solution (1×). Increasing the N supply to 2× or 4× did not induce much change for most parameters, including tissue N concentrations and pNUE. However, aNUE and agNUE decreased gradually as the N supply increased from 1/2× to 4×. In contrast, lowering the N supply, particularly to 1/4× or 1/8×, induced a significant decrease in most measured parameters, except NUEs. The pNUE increased gradually when lowering the N supply from 1× to 1/8×, while aNUE and agNUE were maximal at 1/2 and/or 1/4× according to the cultivar. In contrast, the F v /F m and PSII values remained unchanged. Differences between cultivars were low. However, the O. glaberrima cultivar showed a significantly lower aNUE and agNUE than both O. sativa cultivars under low N supply (1/4 and 1/8×). These results demonstrate that all NUE components were sharply and differentially affected by low N supply, while the PSII remained unaffected. These results are important for determining the cultivar and N supply with the best balance between intensive and sustainable rice cultivation.