Root sprouting in Knautia arvensis (Dipsacaceae): effects of polyploidy, soil origin and nutrient availability

Abstract

Plants able to resprout from roots have a potential bud bank that gets initiated after injury to overcome meristem limitation after loss of all stem parts and to facilitate regeneration. Knautia arvensis is reportedly able to sprout from its roots on arable land, but information is missing regarding such ability in serpentine populations or how it might differ between diploids and tetraploids. We hypothesized that (1) 'ruderal' non-serpentine populations better tolerate severe disturbance than relic, serpentine ones; (2) tetraploid populations resprout more readily than diploids due to enhanced growth of higher ploidy levels; and (3) plants of different ploidy levels from serpentine soils are, for evolutionary reasons, more similar in their response to disturbances than plants from non-serpentine soils. To test these hypotheses, we conducted a pot experiment. Its results do not support our hypothesis that the ability to sprout from roots is a factor driving the spread of new weedy taxa into central Europe or the hypothesis that it is related to polyploidization in the genus Knautia. Both tetraploids and plants from non-serpentine populations regenerated less vigorously than diploids and plants from serpentine populations. However, the genetically closer populations of serpentine origin were more similar in their response to experimental manipulations than their genetically distinct non-serpentine counterparts. The success of non-serpentine taxa in disturbed habitats of central Europe might be related to traits other than the ability to resprout.

Rapid transgenerational effects in Knautia arvensis in response to plant community diversity

“…) with pronounced differences between serpentine or non‐serpentine origins (Martínková et al . ). In a recent genetic study testing K. arvensis seed material of the same commercial seed supplier, Durka et al .…”

The effect of injury on whole-plant senescence: an experiment with two root-sproutingBarbareaspecies

“…The amount of available reserves is closely related to the severity of injury and also to the phenological phase during which the plant is injured. A less advanced life history stage at the time of injury and a larger remaining plant body can provide higher amounts of stored reserves for resprouting (Martínkov a et al, 2008(Martínkov a et al, , 2015Sosnov a et al, 2014). Therefore, more severely injured plants and plants injured during reproduction will form weaker adventitious shoots without strict dominance, in contrast to less severely injured vegetative rosettes in which one adventitious shoot will dominate.…”

“…Apart from the effect of phenology, injury severity can have an effect on further growth of monocarpic plants (Huhta et al, 2003) due to the reduction of apical dominance. A monocarpic plant that has lost part of a dominant shoot will retain apical dominance and thus the main carbohydrate sink to a higher degree than a plant losing the whole shoot and forced to resprout from a root fragment (Martínkov a et al, 2008(Martínkov a et al, , 2015; Bartuškov a and Klimešov a, 2010). Therefore, we could expect that after injury, a monocarpic plant will have a tendency to prolong its life and spread its reproduction over several, more equal reproductive events as is typical for a perennial plant.…”

Evolutionary associations between polyploidy, clonal reproduction, and perenniality in the angiosperms

“…Studies comparing clonal reproduction between ploidy levels within species often do not find that polyploids are more clonal, or more likely to be clonal, than their diploid relatives (e.g. polyploid > diploid: Schlaepfer et al ., ; Van Drunen & Husband, ; polyploids < diploid: Schulze et al ., ; Baldwin & Husband, ; Hanzl et al ., ; Martínková et al ., ; Van Drunen & Husband, ; equivocal: Keeler, ). These discrepancies may reflect how different modes and roles of clonality (Klimeš et al ., ; Vallejo‐Marín et al ., ) can alter the effect of clonal reproduction on polyploid establishment, as well the effect of WGD itself on clonality.…”