Mineral composition of the grains of tropical maize varieties as affected by pre-anthesis drought and rate of nitrogen fertilization

• Published in: Crop science Vol. 45; no. 2; pp. 516 - 523
• Main Authors: Feil, B, Moser, S.B, Jampatong, S, Stamp, P
• Format: Journal Article
• Language: English
• Published: Madison Crop Science Society of America 01.03.2005; American Society of Agronomy
• Subjects: Adaptation to environment and cultivation conditions; Agricultural biotechnology; Agronomy. Soil science and plant productions; Ammonium; ammonium sulfate; application rate; Biological and medical sciences; Corn; crop quality; Crops; Drought; Environmental conditions; fertilizer application; Fertilizers; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Grain; Mineral composition; mineral content; Minerals; Nitrogen; nitrogen fertilizers; nutrient-nutrient interactions; Nutritional aspects; Plant breeding; tropical varieties; Varietal selection. Specialized plant breeding, plant breeding aims; Varieties; water stress; Water supply; Zea mays; Thailand; Asia; South east Asia; United States; Nitrogen fertilization; Monocotyledones; Inorganic analysis; Zea mays; Grains; Tropical zone; Corn; Inorganic element; Cereal crop; Gramineae; Angiospermae; Flowering; Spermatophyta; Endosperm; Drought
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2005.0516

Breeding for higher concentrations of minerals in food crops is one option for improving the health of humans suffering from the consequences of mineral deficiency. The plant breeding approach requires that varietal differences are stable across different environmental conditions. The main objective of our research was, therefore, to determine whether differences in the concentration of grain minerals (P, K, Mg, Ca, Mn, Zn, and Cu) among tropical maize varieties are affected by the level of water and N supply. A 3-yr study with two water regimes (preanthesis drought vs. irrigation throughout the vegetation cycle), three levels of N fertilization (0, 80, 160 kg N ha(-1), applied as ammonium sulfate), and four varieties (Suwan 1, La Posta Sequia, KTX2602, DK888) was conducted in the tropical lowlands of Thailand. The water regime did not affect the mineral composition of the grains. Application of N fertilizer reduced the concentrations of Ca and Zn, and increased the concentration of Mn in the grains. The top yielder, DK888, had the lowest concentrations of N, P, Mg, and Cu in the grain. The varietal differences in the concentrations of grain N and minerals were fairly stable across the levels of N and preanthesis water supply. The varieties that differed most in the grain N and P concentrations (DK888 and KTX2602) had almost the same endosperm/germ dry weight ratio. It remains to be determined whether breeding for high grain yield inevitably lowers the concentrations of grain minerals and protein.