a. Soybean seedlings exposed to sufficient nitrogen (5 mM; top panel) and deficient nitrogen (0.5 mM; bottom panel).
b to d. Growth parameters as affected by nitrogen starvation.
Surface sterilized soybean seeds were germinated on vermiculite and perlite mix (1:3) and grown for 15 days with 5 mM and 0.5 mM nitrogen. Leaf area (b), number of leaves (c) and chlorophyll content (d) were estimated. Values are means ± SE (n=5) from one representative of three independent experiments. Nitrogen was varied by varying levels of exogenously supplied ammonium nitrate.