**4.** *Solidago niederederi*

We have set ourselves the task to study the features of *Solidago* hybrids in northwest Russia, because in contemporary publications the most numerous references to *S. niederederi* are in the northeastern part of Europe and the Pskov region is the closest region of Russia to it. Previously, on the basis of the analysis of the highly variable noncoding chloroplast region rpl32-trnL by Polish botanists, it was found that hybridization between *S. canadensis* and *S. virgaurea* can occur in both

directions and both species can be both mother and father plants [28]. We aimed to determine the situation with respect to parental taxa in the Pskov populations of these species.

The main difference between the hybrid *S. niederederi* and its parents is the structure of shoot systems (mainly the inflorescence structure, **Figure 5**). In *S. canadensis* numerous heads are collected in a compound raceme, and in *S. niederederi* the number of heads is smaller and is collected in a compressed compound raceme, whereas in *S. virgaurea* the number of heads is smaller, and the branches of the compound raceme are so short that the inflorescence is more like a spike.

The size of the heads themselves also varies (**Figure 6**). *S. niederederi* heads have an oval shape and occupy an intermediate position in diameter between parental species, 2201 45 μm (mean error average) with a maximum spread of 1762 to 2728 μm, while for *S. virgaurea* and *S. canadensis*, these values are 3132 30 μm (2874–3548 μm) and 1591 22 μm (1428–1939 μm), respectively [29].

With regard to the length of the head, *S. niederederi* plants in Pskov cannot be clearly distinguished from *S. canadensis* due to the high variability of this indicator in *S. canadensis*. However, in terms of average head lengths, the hybrid also occupies an intermediate position between parent species (**Figure 6**). *S. canadensis* and *S. niederederi* shoots are pubescent, while *S. virgaurea* shoots are glabrous, glossy, and sometimes reddish. The leaves of *S. niederederi* in the middle part of the shoot are linear-lanceolate and dentate along the edge, with three distinct veins (as in *S. canadensis*), while in the basal part of the shoot large, ovate, with reticulate veins (as in *S. virgaurea*). To confirm hybrid origin of S*. niederederi* population in the vicinity of Pskov, nucleotide sequences of nuclear and chloroplast DNA of Pskov individuals (both parent and hybrid species) as well as individuals of parent species from Moscow region were analyzed. The analysis of the ITS1-ITS2 site showed that in all cases of nucleotide substitutions differentiating *S. virgaurea* and *S. canadensis*, *S. niederederi* has ambiguous readings (**Table 2**), indicating heterozygosity, which confirms the hybrid origin of individuals from this population. One sample of *S. canadensis* (c\_3c) showed heterozygosity in three cases of nucleotide substitutions out of four, although morphologically this sample did not differ from other individuals of *S. canadensis,* which indicates the presence of introgressive hybridization

**Figure 5.** *Panicles of* Solidago niederederi *and its parental species.*

**4.** *Solidago niederederi*

*nucleotides are coded using IUPAC nomenclature.*

**Figure 4.**

**102**

**Figure 3.**

We have set ourselves the task to study the features of *Solidago* hybrids in northwest Russia, because in contemporary publications the most numerous references to *S. niederederi* are in the northeastern part of Europe and the Pskov region is the closest region of Russia to it. Previously, on the basis of the analysis of the highly variable noncoding chloroplast region rpl32-trnL by Polish botanists, it was found that hybridization between *S. canadensis* and *S. virgaurea* can occur in both

*Fragment of the trnL-trnF intergenic spacer of chloroplast DNA of various taxa of* Bidens *genus. The*

*Dendrogram based on analysis of the ITS region of DNA of various* Bidens *taxa with bootstrap support data.*

*Invasive Species - Introduction Pathways, Economic Impact, and Possible Management Options*

#### **Figure 6.**

*Parameters of flower heads of* Solidago niederederi *and its parental species: quartiles (first and third), median, maximum, and minimum values are indicated.*


#### **Table 2.**

*ITS1-ITS2 polymorphism for the* Solidago niederederi *hybrid and parental species.*

within the *Solidago* genus. It is likely that this sample is a backcross (result of crossbreeding *S. niederederi* with the parent species *S. canadensis*).

The analysis of the rpl32-trnL high-variable intergenic spacer made it impossible to give an unambiguous answer which species is maternal to *S. niederederi* and which is paternal. In contrast to the results obtained by A. Plizhko and J. Zalevska-Galosh [30], our samples of *S. canadensis* have a higher variability of this section of chloroplast DNA. For example, a sample of s\_3a from the Pskov region has a DNA fragment that is absent in other plants of *S. canadensis* not only in the Pskov region but also near Moscow (242–264 nucleotides, **Table 3**). The area occupying positions 271–306 in the alignment of our sequences (292–330 for sample c\_3a, **Table 3**) and differentiating parental species in Polish populations [30] may differ not only in *S. niederederi* but also in both parental species. The analysis of another noncoding site of chloroplast DNA, trnL-trnF, also failed to answer this question because all the samples examined were identical in this site. Based on the data obtained, we can only

**Sample no.**

**105**

**191**

v\_1a

v\_1b v\_1c n\_2a n\_2b n\_2c c\_3a c\_3b

c\_3c

v\_4 c\_5a c\_5b

*The nucleotides are coded using IUPAC* 

**Table 3.** *Polymorphism*

 *of the rpl32-trnL*

 *region for the Solidago* 

*niederederi*

 *hybrid and parental species.*

A

—

*nomenclature.*

C

—

 —

 —

C

—

C

—

 —

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

A

—

A

GAATCTTAATGTTATGTCTAAA

TGTCTAAAAGAATAATTCTTGTATTTCTT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

C

—

C

—

C

—

C

—

C

—

A

—

**242–264**

**Position in the alignment**

**271–306 (292–330)** TGTCTAAAAGAATAATTCTTGTATTTCTT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

TGTCTAAAAGAATAATTCTTGTATTTCTTGAATTCT

**739–741 (746–748, 709–714)**

T

 T —

—

 T

 T T

 TTTT

—

 TT

T

TTTT

 **894 (900, 923)**

C

*Hybridogenic Activity of Invasive Species of Asteraceae DOI: http://dx.doi.org/10.5772/intechopen.91370*

C

C

C

C

C

A

A

C

C

 C A


*Hybridogenic Activity of Invasive Species of Asteraceae DOI: http://dx.doi.org/10.5772/intechopen.91370*

> **Table 3.**

 *Polymorphism of the rpl32-trnL region for the Solidago niederederi hybrid and parental species.*

within the *Solidago* genus. It is likely that this sample is a backcross (result of

to give an unambiguous answer which species is maternal to *S.*

 *niederederi* with the parent species *S. canadensis*). The analysis of the rpl32-trnL high-variable intergenic spacer made it impossible

niederederi *and its parental species: quartiles (first and third),*

C

C

C

Y

Y

T

T

T

T

C

C

niederederi *hybrid and parental species.*

**384 431 508 549**

A

*Invasive Species - Introduction Pathways, Economic Impact, and Possible Management Options*

A

A

M

M

C

C

M

C

A

A

–306 in the alignment of our sequences (292–330 for sample c\_3a, **Table 3**) and differentiating parental species in Polish populations [30] may differ not only in *S.*

*niederederi* but also in both parental species. The analysis of another noncoding site of chloroplast DNA, trnL-trnF, also failed to answer this question because all the samples examined were identical in this site. Based on the data obtained, we can only

which is paternal. In contrast to the results obtained by A. Plizhko and J. Zalevska-Galosh [30], our samples of *S. canadensis* have a higher variability of this section of chloroplast DNA. For example, a sample of s\_3a from the Pskov region has a DNA fragment that is absent in other plants of *S. canadensis* not only in the Pskov region but also near Moscow (242–264 nucleotides, **Table 3**). The area occupying positions

*niederederi* and

A

A

A

R

R

G

G

R

G

A

A

crossbreeding *S.*

**Figure 6.**

v\_1a

v\_1b

v\_1c

n\_2a

n\_2b

c\_3a

c\_3b

c\_3c

c\_5a

v\_6a

v\_6b

**Table 2.**

*Parameters of flower heads of* Solidago

*median, maximum, and minimum values are indicated.*

**Sample no. Position in the alignment**

T

T

T

Y

Y

C

C

Y

C

T

T

*The nucleotides are coded using IUPAC nomenclature.*

*ITS1-ITS2 polymorphism for the* Solidago

271

**104**

assume that hybridization occurs in both directions in the Pskov population, but there is also a possibility that only one species may be maternal and the other paternal, and it is necessary to search for other, more variable sites of chloroplast DNA.
