Large Effects of Small Water Deficits on Chlorophyll Accumulation and Ribonucleic Acid Synthesis in Etiolated Leaves of Jack Bean (Canavalia ensiformis [L.] DC.).

In the course of investigating RNA metabolism in greening plastids of unexpanded leaves of jack bean (Canavalia ensiformis [L.] DC.) seedlings, it was found that relative humidity had to be controlled in order to obtain reproducible rates of chlorophyll accumulation and 'H-uracil incorporation into newly synthesized RNA. Under high relative humidity conditions, chlorophyll accumulation occurred rapidly in the light while low relative humidity conditions were associated with slow accumulation and much reduced incorporation of radioactive uracil into RNA.