Plants with a winter growth habit flower earlier when exposed for several weeks to cold temperatures, a process called vernalization. We report here the positional cloning of the wheat vernalization gene VRN2, a dominant repressor of flowering that is down-regulated by vernalization. Loss of function of VRN2, whether by natural mutations or deletions, resulted in spring lines, which do not requ...

to evaluate the effects of presence of insect pollinators on quantity and quality of seeds of two common cultivars of onion (allium cepa l.), namely red azar shahr and yellow sweet spanish, an experiment in a factorial randomized complete block design was carried out at two sites. bulbs of equal size were planted with plant to plant 35 cm and row to row 50 cm spacing. at each site, experimental...

to study the effect of glyphosate application rate and timing on johnsongrass (sorghum halepense) vegetative and reproductive growth, three experiments were conducted in field, greenhouse, and laboratory in the agronomy department of university of tehran, karaj, in 2007 & 2008. in each experiment, treatments were arranged in completely randomized (greenhouse & laboratory) and completely randomi...

Most wild and semi-wild species of the genus Gossypium are exhibit photoperiod-sensitive flowering. The wild germplasm cotton is a valuable source of genes for genetic improvement of modern cotton cultivars. A bi-parental cotton population segregating for photoperiodic flowering was developed by crossing a photoperiod insensitive irradiation mutant line with its pre-mutagenesis photoperiodic wi...

The FLOWERING LOCUS T (FT)/TERMINAL FLOWER 1 (TFL1) family proteins play an important role in the regulation of flowering time. In the Arabidopsis thaliana genome, there are six genes in the FT/TFL1 family. To determine how these FT/TFL1 family genes contribute to the regulation of flowering time, this study generated a comprehensive set of mutants (sixty-three multiple mutants in all combinati...

Limited water availability is one of the most prominent abiotic constraints to plant survival and reproduction. Thus, plants have evolved different strategies to cope with water deficit, including modification of their growth and timing of developmental events such as flowering. In this work, we explore the link between flowering time and growth responses to moderate drought stress in Arabidops...

In barley (Hordeum vulgare), PHOTOPERIOD1 (Ppd-H1) acts as a major positive regulator of flowering under long-day conditions, while VERNALIZATION2 (VRN-H2) is a strong repressor of flowering under long days before vernalization. By contrast, CONSTANS (CO) plays a key role in the photoperiodic regulation of flowering in Arabidopsis (Arabidopsis thaliana). Here, we study the role of the closest b...