Sorghum halepense L. (johnsongrass) is one of the world's most noxious weeds, and a paradigm for the potential dangers of crop-weed hybridization. Introduced into the southeastern United States about 200 years ago, S. halepense is a close relative of cultivated sorghum (Sorghum bicolor). Both artificial crossing and experimental field studies have demonstrated the potential for S. halepensex S....

Single sequence repeats (SSR) developed for Sorghum bicolor were used to characterize the genetic distance of 46 different Sorghum halepense (Johnsongrass) accessions from Argentina some of which have evolved toward glyphosate resistance. Since Johnsongrass is an allotetraploid and only one subgenome is homologous to cultivated sorghum, some SSR loci amplified up to two alleles while others (pr...

Invasive plant species often dominate native species in competition, augmenting other potential advantages such as release from natural enemies. Resource pre-emption may be a particularly important mechanism for establishing dominance over competitors of the same functional type. We hypothesized that competitive success of an exotic grass against native grasses is mediated by establishing an ea...

BACKGROUND In a large cropping area of northern Argentina, Sorghum halepense (Johnsongrass) has evolved towards glyphosate resistance. This study aimed to determine the molecular and biochemical basis conferring glyphosate resistance in this species. Experiments were conducted to assess target EPSPS gene sequences and (14)C-glyphosate leaf absorption and translocation to meristematic tissues. ...

BACKGROUND This study aimed to quantify the allelopathic potential of Datura stramonium (Jimson weed). Sorghum halepense (Johnsongrass) tolerance was assessed by germinating, seed and growing seedlings, dosing of photo-synthesis pigments, followed by treatment with D. stramonium extract tropane alkaloids. RESULTS Preliminary chemical analysis of the extracts showed the presence of alkaloids.T...

Johnsongrass (Sorghum halepense) is a striking example of a post-Columbian founder event. This natural experiment within ecological time-scales provides a unique opportunity for understanding patterns of continent-wide genetic diversity following range expansion. Microsatellite markers were used for population genetic analyses including leaf-optimized Neighbor-Joining tree, pairwise FST, mismat...

Sunflower is an important industrial crop since it grown all over the world for oil production, while Johnsongrass (Sorghum halepense (L.) Pers.) characterized by great competitiveness and can severely impair plant growth productivity. Thus, a two-year field experiment was conducted to evaluate impact of control practices on growth, seed yield, content sunflower crop. The results indicated that...