Effect of pod removal on absorption and reduction of nitrate in soybean

Elevated CO2concentrations increase leaf nitrate reduction by strengthening sink activity in soybean plants

“…The assimilation of N in the leaf can he significantly influenced by the demand for N assimilates from the growing sink organs (Deane-Drummond and Clarkson 1979;Crafts-Brandner et al 1984;Pan et al 1986;Fujita et al 1997). In soybean leaf, the nitrate reductase activity was found to decrease significantly when pods were removed from the plant (Fujita et al 1997), suggesting that the sink activity of the plant can be a factor controlling the enzyme activity. In the present study, the effect of CO 2 enrichment on biomass production in relation to photosynthesis and nitrogen metabolism has been investigated to identify the factors responsible for the regulation of nitrate reduction and utilization in soybean plants.…”

“…In a series of investigations in our laboratory, it was revealed that the reduction of the sink activity by the removal of growing pods in soybean decreased nitrate uptake and reduction (Fujita et al 1988(Fujita et al , 1991. The assimilation of N in the leaf can he significantly influenced by the demand for N assimilates from the growing sink organs (Deane-Drummond and Clarkson 1979;Crafts-Brandner et al 1984;Pan et al 1986;Fujita et al 1997). In soybean leaf, the nitrate reductase activity was found to decrease significantly when pods were removed from the plant (Fujita et al 1997), suggesting that the sink activity of the plant can be a factor controlling the enzyme activity.…”