The carry-over effect of sub-lethal herbicides was investigated on the germination of seeds collected from surviving Chenopodium album plants, which had received 1/8, 1/8 twice, 1/8 three times, 1/4, 1/2, 1/1 doses of either pre-emergence ioxynil or post-emergence bentazone in a previous onion (Allium cepa) crop. Seeds were also collected from surviving C. album plants, which had received 1/4, ...

Temperature ( T ) and water potential ( y ) are two primary environmental regulators of seed germination. Seeds exhibit a base or minimum T for germination ( T b ), an optimum T at which germination is most rapid ( T o ), and a maximum or ceiling T at which germination is prevented ( T c ). Germination at suboptimal T can be characterized on the basis of thermal time, or the T in excess of T b ...

Plant seeds will not germinate when in a dormant state. What then are the factors controlling dormancy? A recent study has uncovered two basic-helix-loop-helix proteins which repress germination and are critical for maintaining dormancy. The combined action of light and cold synergistically alleviates activity of these repressors thus stimulating germination.

The effect of heavy metal ions (Cd, Cr 3+ , Cu 2 , Ni, Pb 2+ and Zn) on the growth and germination of conidia of the aphid pathogenic fungus Pandora neoaphidis was studied. The metal ions were added into the culture medium in three concentrations: A – concentration corresponding to the mean content of that metal in Polish soils, B – concentration 10-times higher and C – 100-times higher than th...

environmental stresses specially drought, play an important role in decreasing plant growth, particularly during germination in dry and semi dry area. to considering the effect of drought stress caused by polyethylene glycol on germination and characteristics of 2 spices of sesamum indicum, we had done factorial and complete accidental plot with 4 treatments and 3 times repetition. experimental...

BACKGROUND AND AIMS The purpose of this study was to compare the relative accuracy of different thermal-germination models in predicting germination-time under constant-temperature conditions. Of specific interest was the assessment of shape assumptions associated with the cardinal-temperature germination model and probit distribution often used to distribute thermal coefficients among seed sub...

The timing of germination is a key life-history trait that may strongly influence plant fitness and that sets the stage for selection on traits expressed later in the life cycle. In seasonal environments, the period favourable for germination and the total length of the growing season are limited. The optimal timing of germination may therefore be governed by conflicting selection through survi...

UNLABELLED • PREMISE OF THE STUDY Assessing seed quality in orchids has been hindered by stringent germination requirements. Seed quality has traditionally been assessed in orchids using in vitro or in situ germination protocols or viability staining. However, these methods are not always well suited for rapid assessment of viability in the context of ecological studies.• METHODS The potent...

We study dynamical aspects of the q-state Potts model on an n × n box at its critical βc(q). Heat-bath Glauber dynamics and cluster dynamics such as Swendsen–Wang (that circumvent low-temperature bottlenecks) are all expected to undergo “critical slowdowns” in the presence of periodic boundary conditions: the inverse spectral gap, which in the subcritical regime is O(1), should at criticality b...