JXB Advance Access originally published online on September 5, 2005
Journal of Experimental Botany 2005 56(421):2821-2829; doi:10.1093/jxb/eri274
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
Perturbed reproductive development in salt-treated Sorghum bicolor: a consequence of modifications in regulation networks?
The Judea Center for Research and Development, Carmel, 90404, Israel
* Fax: +972 2 9960061. E-mail: nissamz{at}bgumail.bgu.ac.il
In Sorghum bicolor, tolerance to salinity is improved by a 3-week treatment with 150 mM NaCl during early vegetative development. However, a strong decrease in fertility is also observed, suggesting that reproductive development becomes perturbed by this adaptive response to salinity. This study is an attempt to clarify the origin of such a paradoxical phenomenon. The relationships between end-cycle characters are modified by the NaCl treatment: some linkages disappear, while others are strengthened, especially those linking fertility with plant height. In parallel, a transient reduced level of linkage between leaf characters is observed around the unfolding of the eighth to the tenth leaves, defining a critical period in vegetative development separating two discrete phases. A relationship is observed between events occurring during this short critical period and the NaCl-induced perturbations in fertility. This suggests that reproductive development is conditioned by the influence of salinity on events occurring during a short period of vegetative development, independently of the level of tolerance to salinity quantified by the rate of vegetative growth.
Key words: Connectance, critical period, fertility, individuality, phenotypic plasticity, regulation networks, salinity