Figure 7.

In vitro culture of urease-positive (Eu3/Eu3 or Eu3/eu3-e1) and urease-negative (eu3-e1/eu3-e1) immature cotyledons. After detaching the two cotyledons from a given embryo, one was cultivated on mock exudate (ME) or nitrogen-free medium (No N), whereas the other cotyledon was cultivated on Arg. Fresh weight, total protein, and total urea were determined in each cotyledon after 6 d of culture. A, Fresh weight increase (gray bars) and total protein (white bars) relative to values of paired cotyledon cultured on Arg, established as 100%. B, Total urea accumulation in cotyledon and culture medium. Results are means ± sd of three separate experiments.