Fenugreek root exudates show species-specific stimulation of Orobanche seed germination

Weed Research ◽  
2008 ◽  
Vol 48 (2) ◽  
pp. 163-168 ◽  
Author(s):  
M FERNÁNDEZ-APARICIO ◽  
A ANDOLFI ◽  
A EVIDENTE ◽  
A PÉREZ-DE-LUQUE ◽  
D RUBIALES
2006 ◽  
Vol 408 (1) ◽  
pp. 223-225 ◽  
Author(s):  
V. I. Kolmakov ◽  
M. I. Gladyshev ◽  
E. S. Kravchuk ◽  
S. M. Chuprov ◽  
O. V. Anishchenko ◽  
...  

1979 ◽  
Vol 9 (9) ◽  
pp. 665-670 ◽  
Author(s):  
Andrei A. Augustin ◽  
Michael H. Julius ◽  
Humberto Cosenza

2014 ◽  
Vol 28 (1) ◽  
pp. 266-271 ◽  
Author(s):  
Salam A. Al-Thahabi ◽  
Jed B. Colquhoun ◽  
Carol A. Mallory-Smith

Small broomrape is a holoparasitic plant that attaches to the roots of red clover as well as several other host plants. Hosts and false hosts produce stimulants that induce small broomrape germination but small broomrape does not attach to a false host. Wheat has been identified as a false host for small broomrape; therefore, studies were conducted to investigate the effect of red clover and wheat root exudates on small broomrape germination. In one study, the effect of exudates from red clover and wheat at multiple growth stages on small broomrape germination was evaluated. Red clover induced small broomrape germination at all growth stages tested but was greatest (78%) in the presence of exudates from red clover at the three-trifoliolate stage. Maximum small broomrape germination was 25% when exposed to exudates produced by one-leaf-stage wheat. In a second study, the relationship between small broomrape germination and host growth condition was evaluated using root exudates from red clover or wheat grown under several temperature conditions for either 4 or 8 wk. For the different temperatures, there were no differences in small broomrape germination when exudates of red clover grown for 4 wk were used. Small broomrape germination was reduced when exposed to exudates from red clover plants grown for 8 wk at 10 C compared with plants grown at 15, 20, and 25 C. Differences in small broomrape seed germination were observed with temperature under which wheat was grown for 4 wk, but not for 8 wk. Although wheat exudates resulted in less small broomrape seed germination than red clover exudates, growing wheat as a false host in a small broomrape-infested field could be an important component of an integrated management plan.


Semiotica ◽  
2016 ◽  
Vol 2016 (208) ◽  
pp. 1-20
Author(s):  
John Deely

AbstractJohn Poinsot (1589–1644), aka Joannes a Sancto Thoma, was the first of St Thomas’ followers among the Latins to demonstrate that the origins of animal knowledge in sensation is already – from the first – a matter of the action of signs. This action, “semiosis,” results in the formation of an irreducibly triadic relation apart from which there is no awareness at all on the part of animals. At the level of internal sense, and then again at the level of intellect (the two having in common dependency upon concept-formation in order to interpret the data provided by sensation), Poinsot shows how the concept serves to make objects known only by serving as the foundation for relations which, exactly as those in sensation, exhibit an irreducibly triadic character, with only this difference: that, whereas the triadic relations of sensation are directly founded upon or “provenate from” species impressa (stimulation of sense powers in bodily interaction with the surroundings) determining the external sense powers, the triadic relations of perceptual and intellectual awareness have as their immediate foundations or “sources of provenation” species expressae (“ideas” or concepts) actively formed by the cognitive powers of memory, imagination, estimation, and intellect. Being relations, all of these triadic relations exhibit no direct instantiation as signate matter, and it is this which makes them only indirectly knowable to sense powers. Intellect, by contrast, in being able to know relations precisely in their difference from related objects and things, manifests the species-specific distinctness of human animals in being able to construct and to know and to communicate about objects – beginning with relations – which admit of no direct sensory instantiation. The purpose of this paper is to show how the ability of the human mind to consider objects which admit of no direct instantiation in sense perception is what distinguishes the human being as “semiotic animal” from what the Latins identified as “brute animals,” not because brutes (the “alloanimals,” to use a term from late modern anthropology) are not “rational” in the modern sense of being able creatively to work through problems (indeed they are rational in this sense!), but because human animals are not confined to the consideration of objects as perceptually instantiable.


Sign in / Sign up

Export Citation Format

Share Document