Effect of Light Quality, Light Intensity and Temperature on Pigment Accumulation in Barley Seedlings

Active iiitochonidrial preparationls were obtained from the peel of young Faris sweet lemonis. The high buffer capacity of the grinding solution and the miiaintenanice of a slightly alkalinie reaction while griniding the tissues (lirectlv in the solutioni obviate(d inactivation of the mitochonidria usually associated with a low 1)H. Citric aci(d occurred in a lower concenitration thani niialic acid in the Faris sweet lemon. Oxidative phosphorylation was obtained with citrate, oa-ketoglutarate, succinate, and malate as substrates. Wlhen citrate-1, 5-C14 was used as a substrate. labeled aketoglutarate was found after 60 minutes and labeled malate after 120 minutes. When succinate-1, 4-C'4 was used as a substrate, malate and fumarate were found after 60 minutes and also citrate after 120 minutes. WVhen pyruvate-3-C'4 was used as a substrate together with a sparker acid. citrate, a-ketoglutarate, and malate were found after 120 minutes. These findings, together with the inhibitory effects of cyanide and malonate, indicated the citric acid cycle was operative in this variety of lemon.