Relationships between nitrate level, nitrate reductase activity and anaerobic nitrite production inPisum sativum leaf tissue

Anaerobic nitrite production (the in vivo NO 3 -R activity) in an incubation medium lacking exogenous nitrate but containing 0.5% n -propanol and 0.1% Triton X-100 showed higher correlation ( y - ax b ) with the level of endogenous nitrate in Pisum sativum L. leaves than the in vitro nitrate reductase activity. The in vivo NO 3 -R activity correlated well with the in vitro activity up to the 50 ppm NO 3 -N level of endogenous nitrate. The ratio in vivo: in vitro activity slightly decreased with increasing level of endogenous nitrate in leaf tissue.