Effects of molybdenum on nitrogen metabolism of sugarcane
Two Brazilian nitrogen fixing sugarcane varieties B1 and B8 were employed as the plant materials.They were cultured with nutrition solution that contained different levels of Mo i.e. 0mg/L, 0.01mg/L, 0.02mg/L and 0.04mg/L, respectively, in pot trial with sand in greenhouse. the activities of nitrate reductase (NR)and glutamine synthetase (GS), and the contents of NO3--N and NH4+-N were measured at different stages. The results showed that under nitrogenous conditions in the greenhouse, all the Mo treatments increased the activity of NR and decreased the NO3--N content compared with the control for both B1 and B8. As a result, the treatment with 0.01mg/L Mo increased the activity of GS in B1 after initial elongation stages and that in B8 at young seedling stage, and it also decreased the NH4+-N content to improve the nitrogen metabolism. Under non-nitrogenous conditions, after initial elongation stage, the activity of NR was increased and the NO3--N content was decreased in both sugarcane varieties treated with different levels of Mo. Furthermore, the activity of GS was higher than the control of B1 and the NH4+-N content was lower in leaves of B8 at tillering stage. Obviously, the effect of different Mo treatment on the process of nitrogen metabolism and ammonia assimilation at different stages was different under nitrogenous or nonnitrogenous condition, but the lower concentration of Mo could increase the activities of NR and GS absolutely, decrease the contents of NO3--N and NH4+-N in leaf of the two sugarcane varieties, and improve the nitrogen metabolism and ammonia assimilation.
国家科技期刊平台
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万方数据
维普
