Effects of applying different nitrogen form on cherry tomato nitrogen metabolism during fruit development

• Published in: Ying yong sheng tai xue bao Vol. 21; no. 9; p. 2335
• Main Authors: Li, Qing-yu, Xu, Xin-juan, Gu, Hai-long, Gao, Hong-yan, Zhu, Yi-yong, Dong, Cai-xia, Shen, Qi-rong
• Format: Journal Article
• Language: Chinese
• Published: China 01.09.2010
• Subjects: Culture Techniques - methods; Fertilizers; Fruit - growth & development; Fruit - metabolism; Gene Expression Regulation, Plant - drug effects; Glutamate-Ammonia Ligase - metabolism; Lycopersicon esculentum - genetics; Lycopersicon esculentum - growth & development; Lycopersicon esculentum - metabolism; Nitrates - metabolism; Nitrogen - chemistry; Nitrogen - metabolism; Quaternary Ammonium Compounds - metabolism
• ISSN: 1001-9332

A hydroponic experiment was conducted to study the effects of applying 100% NO3- -N, 100% NH4+ -N, and 75% NO3- -N+25% NH4+ -N on the nitrogen metabolism and the nitrate reductase (NR) and glutamine synthetase (GS) gene expression of cherry tomato during its fruit development. Applying 75% NO3- -N+25% NH4+ -N slightly increased the single fruit mass, and increased the fruit NH4+ -N, total amino acid, and total N contents and N accumulation significantly, compared with applying 100% NO3- -N. In treatments 100% NO3- -N and 75% NO3- -N + 25% NH4+ -N, the fruit NR activity and its gene expression had no significant difference, but were higher than those in treatment 100% NH4+ -N. The fruit GS activity was significantly higher in treatment 75% NO3--N+25% NH4+ -N than in treatment 100% NO3- -N. In the three treatments, isozyme GS1 (Cytosolic type GS) and GS2 (Chloroplast type GS) expression was inconsistent with GS activity, suggesting that the effects of applied N on GS activity could be mainly reflected at posttr