Invasive Russian Knapweed (Acroptilon repens) Creates Large Patches Almost Entirely by Rhizomic Growth

Abstract

Russian knapweed is an outcrossing perennial invasive weed in North America that can spread by both seed and horizontal rhizomic growth leading to new shoots. The predominant mode of spread at the local scale and dispersal at the long-distance scale informs control but has not been quantitatively researched. We used amplified fragmentlength polymorphisms (AFLPs) of DNA collected from 174 shoots in two discrete patches of Russian knapweed at each of three locations in Montana. Out of the 174 shoots collected, we found nine AFLP genotypes. Three out of the six patches were monotypic; the other three patches each had one rare genotype. No genotypes were shared between patches. The maximum diameter of a genet (a genetic individual) was 56.5 m. These results indicate that patch expansion at the local scale is almost entirely by rhizomes that spread and develop new shoots. At the longdistance scale, dispersal is by seed. Controlling seed development through biological control and herbicide use may be effective at stopping long-distance dispersal but may not affect expansion of existing patches. Nomenclature: Russian knapweed, Acroptilon repens (L.) DC, Rhaponticum repens (L.) Hidalgo, Centaurea repens L.

Next-gen plant clonal ecology

“…Combined reproduction by seed and clonal growth can enable species to spread on two scales at once, distances of meters to hundreds of meters by seeds and over centimeters to meters by clonal growth, analogous to the spread of wildfire by airborne sparks that set small individual fires. For example, the invasive, clonal species Acroptilon repens and Phragmites australis can produce an advancing front of growing patches (Duncan et al, 2017;Gaskin and Littlefield, 2017).…”

Effect of Afghan Talkhak (Acroptilon Repens) Aqueous Extract on Blood Glucose Level in Diabetic Rats

“…This allows the plant to survive for long-term (15). A. Repens found natively in European and Asian countries, including Mongolia, Western Turkestan, Turkey, minor Asia, middle Asia, Iran, Iraq and Afghanistan (17)(18)(19)(20).…”