Differences in NH3 compensation point among tobacco (Nicotiana Tabacum L.) cultivars and its relationship with nitrogen metabolism
To investigate NH3 compensation point (xs) and its differences in leaves of three flue-cured tobacco genotypes, foliar apoplastic NH4+ concentration and pH were measured by apoplast extraction technique, the xs (25℃) was calculated, and the activities of related enzymes and nitrogen parameters of leaves were also analyzed.In the leaves of the three cultivars, an increase in xs was observed in leaves during senescence.Compared with the leaves of slow-senescing cultivar, the leaves of the rapid-senescing tobaccocultivar with lower N status had a stronger decrease in glutamine synthetase activity ( GS, EC 6.3.1.2) and a more substantial increase in xs.These results indicate that the cultivars with rapid senescence and low nitrogen content in leaves may have a high potential for NH3 emission from senescing leaves into the atmosphere, and the difference in xs values is related with the N metabolism of the cultivars.
国家科技期刊平台
NSTL
万方数据
维普
