Both salicylic acid and ferricyanide induce flowering in the long-day plant Lemna gibba L., strain G3 under 8- and 9-hour short days. In both cases the effect is daylength-dependent. Salicylic acid is ineffective on daylengths less than 8 hours and ferricyanide is ineffective on daylengths less than 5 hours. When both substances are given together a striking synergistic interaction is observed,...

In this work, we study if ploidy (i.e. number of copies of chromosomes) in the oyster Crassostrea gigas may introduce differences in behavior and in its synchronization by the annual photoperiod. To answer to the question about the effect of the seasonal course of the photoperiod on the behavior of C. gigas according to its ploidy, we quantified valve activity by HFNI valvometry in situ for 1 y...

Laboratory rats traditionally are classified as nonphotoperiodic because variations in daylength have little or no effect on their gonadal function. After olfactory bulbectomy, however, rats show clear evidence of photoperiodic regulation of the gonads. The present study demonstrates, by means of resonance experiments, that the testicular response to daylength in rats is mediated by a circadian...

Timing of the floral transition and inflorescence development strongly affect yield in barley (Hordeum vulgare). Therefore, we examined the effects of daylength and the photoperiod response gene PHOTOPERIOD1 (Ppd-H1) on barley development and analyzed gene expression changes in the developing leaves and main shoot apices (MSAs) of barley by RNA sequencing. The daylength sensitivity of MSA devel...

WANG 2. M.. JOHXEN K. H. and LECHO~VICZ iM. J. Is climate simulatiori in growth chambers necessary? BIOTRONICS 28, 13-21, 1999. In the expression of their genetic potential as phenotypes, trees respond to environmental cues such as photoperiod, temperature and soil and atmospheric water. However, growth chamber experiments often utilize simple and standard environmental conditions that might no...

Flowering of Arabidopsis is promoted by long days and delayed by short days. Mutations in the GIGANTEA (GI) gene delay flowering under long days but have little or no effect under short days. We have now isolated the GI gene and show that it encodes a novel, putative membrane protein. By comparing the sequence of the Arabidopsis gene with that of a likely rice orthologue and by sequencing mutan...