Journal of Taiwan Agricultural Research

Author:Guang-Jauh Shieh*, Wen-Long Tsaur, Huey-Ru Wu and Hung-Shung Lu

Abstract:

    To evaluate the relationships between ammonium assimilation enzyme activity and dry weight accumulation in maize seedling, seedlings of 4 inbred lines and 4 hybrids were grown in sand culture and supplemented with 50 mM NH₄⁺ concentration at different plant stages in green house. Seedling harvested at 18 days after supplemented ammonium-nitrogen (NH₄⁺-N) and determined for gross differences in dry mass and ammonium assimilation enzyme activities. The results revealed that the plant stage, genotype and genotype Î plant stage interaction were significantly different for all traits in maize seedling. The GS (glutamine synthetase) activity, shoot dry weight accumulation, root dry weight accumulation, total dry weight accumulation, and the ratio of shoot/root were up follow by plant stages increasing. The TA85-17 Î H95 has largest total dry weight accumulation, next by the A661 and the ICAL210 and TA85-17 has smaller total dry weight accumulation. The correlation analysis indicated that there has positive correlation between plant stages and GS activity, shoot dry weight accumulation, root dry weight accumulation, total dry weight accumulation, and the ratio of shoot/root in maize seedling. But there has negative correlation between plant stages and GDH (glutamate dehydrogenase) activity, protein content. Besides, the enzymatic activities of GS, GDH, and GOGAT (glutamate Synthase) and the increase of biomass in different genotypes of maize did not show any correlation relationship. Also there were non-correlation between ammonium assimilation enzymes activities and dry weight accumulation in maize seedling. The protein content and the GDH activity had positive correlation. But the protein content between shoot dry weight accumulation, root dry weight accumulation, total dry weight accumulation, and the ratio of shoot/root had negative correlation.

Key words:Maize, Ammonium (NH₄⁺), Seedling dry weight accumulation, Ammonium assimilation enzyme, Correlation

Download: PDF Links