Photoperiodic Regulation of Tuber Enlargement in Water Yam

Photoperiodic regulation

Adult male wild rabbits were exposed to artificial daylengths of 8L:16D, 13L:1 1D or 20L:4D after being taken from the wild during September, when testicular size was minimal. In all groups the testes grew and those in 20L:4D grew more quickly than did those in 8L:16D or 13L:11D. Rabbits kept in the 3 daylength treatments for the whole study maintained enlarged testes after the initial growth p...

Photoperiodic regulation of puberty in seasonal species.

Puberty occurs seasonally in the majority of mammals native to temperate or arctic latitudes, and in species with sufficiently long life spans puberty can be considered to reoccur on an annual basis. The precise timing of puberty and the annual reoccurrence of fertility reflects an interaction of changes in ambient daylength (photoperiod) and endogenous long-term timing processes, which in some...

Cell division and cell enlargement during potato tuber formation

Regulation of photoperiodic flowering by Arabidopsis photoreceptors.

Photoperiodism is a day-length-dependent seasonal change of physiological or developmental activities that is widely found in plants and animals. Photoperiodic flowering in plants is regulated by photosensory receptors including the red/far-red light-receptor phytochromes and the blue/UV-A light-receptor cryptochromes. However, the molecular mechanisms underlying the specific roles of individua...

Purification and Characterization of A Novel Chitinase Isozyme from Yam Tuber.

A new chitinase isozyme (Chitinase A), which had only one optimum pH toward a long substrate, glycolchitin, was purified from the peel of yam tuber by CTAB (hexadecyl trimethyl ammonium bromide) treatment and ammonium sulfate fractionation, followed by column chromatography on DEAE-Cellulofine A-500, chromatofocusing, and gel filtration on Sephacryl S-100. The molecular weight was 28,000 by SDS...