Changes of anatomical features, photosynthesis and ribulose bisphosphate carboxylase-oxygenase content of mango leaves.
Nii N., Watanabe T., Yamaguchi K., Nishimura M.
Author Affiliation: College of Agriculture, Meijo University, Tempaku, Nagoya 468, Japan.
Annals of Botany 76 : 649-656
Abstract : Leaves of 4-year-old, greenhouse-grown, potted mango cv. Irwin seedling trees were sampled at different stages of development in 2 seasons, from Nov. to Dec. 1993 and from Mar. to Apr. 1994. Leaf anthocyanin concentration began to decrease as leaves approached their maximum area, and chlorophyll concentration increased. Leaf thickness decreased at the start of leaf development, then increased when chlorophyll accumulation began. In mature leaves, chloroplasts were characterized by abundant starch grains, distributed within palisade cells. With starch accumulation, chloroplast nucleoids (ct-nuclei) were displaced to the peripheral regions of the chloroplasts. Net photosynthetic rate (Pn) was below the CO2 compensation point in immature and chocolate-coloured leaves, increased as leaves became reddish-brown and increased above the compensation point as leaves turned green, reaching an average in mature leaves of 7.6 mg CO2?dm-2h-1. The content of ribulose-bisphosphate carboxylase protein increased concomitantly with Pn.