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Botanical Journal of the Linnean Society, 2008, 157, 141–154. With 78 figures
A palynological study of the genus
Mentha L. (Lamiaceae)
SEVCAN CELENK*, GUL TARIMCILAR, ADEM BICAKCI, GONUL KAYNAK and
HULUSI MALYER
Department of Biology, Faculty of Science, Uludag University, Gorukle, 16059, Bursa, Turkey
Received 19 April 2007; accepted for publication 24 October 2007
The pollen morphology and exine structure of 10 Mentha L. species were investigated using light microscopy and
scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes
and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized
in M. ¥ dumetorum. The exine was bireticulate in section Pulegium, and reticulate in section Menthae. A correlation
was found between pollen size and chromosome number. The results indicate that the pollen characters of the
genus Mentha are valuable for taxonomic applications and may be useful for classification. © 2008 Uludag
University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society,
2008, 157, 141–154.
ADDITIONAL KEYWORDS: light microscopy – pollen morphology – scanning electron microscopy – Turkey
– Labiate.
INTRODUCTION branches subequal, nutlets smooth, reticulate or
tuberculate (Tutin & Heywood, 1972).
The genus Mentha L. (mint), comprising c. 25 species Mints were already grown in antiquity for the
of herbaceous perennial (rarely annual) plants, is a extraction of essential oil and for medicinal use, and
member of the subfamily Nepetoideae, tribe Men- they attained a wide distribution in the Middle
theae. Mints are distributed chiefly in the temperate Ages. Their prolonged cultivation has contributed to
regions of the Old and New World, where they are the formation of many hybrid forms; these are mostly
widespread and abundant (Shishkin, 1976; Harley & propagated vegetatively, by means of rootstock
Brington, 1977; Kokkini, 1991). The genus Mentha division, stem cuttings, and even leaf cuttings.
is grouped into five sections and is characterized The species widely occurring in cultivation include
by the following characters: flowers hermaphrodite M. ¥ piperita L., M. spicata L., M. arvensis L., and a
or female, on the same or different plants, usually few others. Most of the cultivated mints are of hybrid
in dense, many-flowered verticillasters, sometimes origin. The pollen morphology of 11 taxa, four of
forming a long spike-like inflorescence or a terminal which are hybrids, was investigated in this study.
head. Calyx actinomorphic or weakly two-lipped, They belong to two sections: section Pulegium is rep-
tubular or campanulate, 10–13-veined, with five(four) resented only by M. pulegium L. (2n = 20), and section
subequal or rarely unequal teeth. Corolla weakly two- Menthae consists of ten taxa: M. aquatica L. (2n = 96),
lipped, with four subequal lobes, the upper lobe wider M. ¥ dumetorum Schultes (2n = 60), M. longifolia (L.)
and usually emarginate; tube shorter than the calyx. Hudson ssp. longifolia (2n = 24), M. longifolia (L.)
Stamens about equal, divergent or ascending under Hudson ssp. typhoides (Briq.) Harley var. typhoides
the upper lip of the corolla, exerted (except in (2n = 24), M. ¥ piperita L. (2n = 72), M. ¥ rotundifolia
M. pulegium, some hybrids, and female flowers). Style (L.) Huds. (2n = 24), M. spicata L. ssp. spicata
L. (2n = 48), M. spicata ssp. tomentosa (Briq.) Harley
*Corresponding author. E-mail: sevcant@uludag.edu.tr (2n = 48), M. suaveolens Ehrh. (2n = 24), and
© 2008 Uludag University. Journal compilation 141
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142 S. CELENK ET AL.
Table 1. Pollen morphological data (mean values, standard deviations, and variations) of Mentha species
Taxon P E P/E Pollen shape
M. aquatica 39.58 ± 3.01 (34.18–43.48) 39.56 ± 2.62 (32.56–44.72) 1.00 Spheroidal
M. ¥ dumetorum 42.33 ± 3.19 (38.05–48.12) 41.27 ± 3.30 (36.98–48.40) 1.03 Prolate-spheroidal
M. longifolia ssp. longifolia 30.11 ± 2.04 (26.42–32.71) 30.82 ± 2.33 (26.01–34.66) 0.98 Oblate-spheroidal
M. longifolia ssp. typhoides 31.02 ± 1.36 (29.11–33.99) 34.05 ± 3.44 (30.81–41.01) 0.91 Oblate-spheroidal
var. typhoides
M. ¥ piperita 26.97 ± 2.43 (23.61–31.50) 29.35 ± 2.96 (25.10–36.61) 0.92 Oblate-spheroidal
M. pulegium 23.47 ± 1.76 (20.53–26.78) 25.14 ± 1.64 (22.65–28.84) 0.97 Oblate-spheroidal
M. ¥ rotundifolia 23.67 ± 2.59 (20.87–29.74) 24.27 ± 3.01 (17.32–30.02) 0.98 Oblate-spheroidal
M. spicata ssp. spicata 30.01 ± 2.87 (27.35–34.70) 31.08 ± 1.55 (28.76–34.62) 0.97 Oblate-spheroidal
M. spicata ssp. tomentosa 29.02 ± 1.63 (26.85–31.10) 31.67 ± 3.70 (28.00–38.93) 0.92 Oblate-spheroidal
M. suaveolens 21.53 ± 4.66 (17.46–26.61) 20.16 ± 0.44 (19.65–20.45) 0.87 Suboblate
M. ¥ villosa-nervata 26.90 ± 1.40 (25.88–28.84) 25.72 ± 3.79 (19.83–28.38) 1.13 Prolate-spheroidal
E, equatorial axis; P, polar axis. All measurements in mm.
M. ¥ villosa-nervata Opiz (2n = 36) (chromosome MATERIAL AND METHODS
count references: Davis, 1982; Tarimcilar & Kaynak,
2004). Most of the Mentha species are characterized Pollen for examination by LM was prepared accord-
by large morphological variations, as reflected by the ing to the Wodehouse method (Wodehouse, 1935).
large number of names at different taxonomic ranks Pollen grains of the 11 recognized taxa of Mentha,
attributed by taxonomists to mints during the past M. aquatica, M. ¥ dumetorum, M. longifolia ssp.
200 years. Furthermore, intra- and interspecific longifolia, M. longifolia ssp. typhoides var. typhoides,
hybridization occurs commonly when the species of M. ¥ piperita, M. pulegium, M. ¥ rotundifolia, M. spi-
section Menthae meet sympatrically with each other, cata ssp. spicata, M. spicata ssp. tomentosa, M. sua-
leading to the complex variation patterns that char- veolens, and M. ¥ villosa-nervata, were mostly taken
acterize most wild populations. from herbarium material housed at the herbarium of
Investigations of pollen morphology in the Lami- Uludag University (BULU). The polar axis (P), equa-
aceae have been essential as an aid to classification torial axis (E), colpus length (Clg) and width (Clt),
within this family (Erdtman, 1945; Harley et al., apocolpium diameter, and mesocolpium, exine, and
1992; Abu-Asab & Cantıno, 1994). Pollen morpho- intine thickness were measured on the pollen grains.
logical studies for the Lamiaceae have been carried Measurements and light micrographs were taken
out by several authors (for example, Erdtman, 1945; with an Olympus BX 51 microscope. The measured
Abu-Asab & Cantıno, 1992, 1994; Harley, 1992; pollen diameters were based on at least 20 samples
Wagstaff, 1992), but only a few studies have been and other characters on approximately 10 samples
conducted on the genus Mentha. Jancic & Polic under the light microscope (¥ 1000). The details are
(1989) studied the pollen morphology of five Mentha given in Table 1. The collections examined are listed
species. Gocmen, Tarımcılar & Kaynak (1997) in the Appendix.
studied six Mentha species from Turkey. Perveen & For SEM, pollen grains were transferred directly to
Qaiser (2003) investigated the pollen morphology of a double-sided tape-affixed stub and micrographs
the three Mentha species from Pakistan. In addi- were obtained using an XL-30 ESEM-FEG/PHILIPS
tion, pollen grains of three Mentha species appear microscope. All of the measurements were performed
on the web pages of Paldat (a palynological data- using CARNOY 2.0. Analysis of variance (ANOVA)
base) (Ulrich, 2000). and Scheffe’s range test were applied for statistical
The objectives of this paper were to provide a evaluation (Sokal & Rohlf, 1981).
detailed account of the pollen morphology of Mentha In general, the pollen terminology follows Faegri &
as a whole by light microscopy (LM) and scanning Iversen (1975), Harley et al. (1992), and Punt et al.
electron microscopy (SEM), and to determine the (1994).
extent to which these palynological data can be
used as a taxonomic character in the genus. This RESULTS AND DISCUSSION
paper presents a detailed account of the pollen
morphology of 11 taxa of Mentha collected from The pollen grains are monads, six-zonocolpate (very
Turkey. rarely intermixed with eight or four colpate grains) or
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PALYNOLOGY OF MENTHA L. (LAMIACEAE) 143
Figures 1–20. Light micrographs of pollen grains of Mentha. Figs 1–5. M. aquatica. Figs 6–8. M. longifolia ssp. longi-
folia. Figs 9–12. M. longifolia ssp. typhoides var. typhoides. Figs 13–16. M. ¥ piperita. Figs 17–20. M. pulegium. Figs 1, 5,
9, 13, 17. Equatorial view and high focus. Figs 2, 6, 10, 14, 18. Equatorial view and low focus. Figs 3, 7, 11, 15, 19. Polar
view and high focus. Figs 4, 8, 12, 16, 20. Polar view and low focus. Scale bars, 10 mm.
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144 S. CELENK ET AL.
Figures 21–40. Light micrographs of pollen grains of Mentha. Figs 21–24. M. ¥ rotundifolia. Figs 25–28. M. spicata ssp.
spicata. Figs 29–32. M. spicata ssp. tomentosa. Figs 33–36. M. suaveolens. Figs 37–40. M. ¥ villosa-nervata. Figs 21, 25,
29, 33, 37. Equatorial view and high focus. Figs 22, 26, 30, 34, 38. Equatorial view and low focus. Figs 23, 27, 31, 35, 39.
Polar view and high focus. Figs 24, 28, 32, 36, 40. Polar view and low focus. Scale bars, 10 mm.
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PALYNOLOGY OF MENTHA L. (LAMIACEAE) 145
Figures 41–54. Light micrographs of pollen grains of Mentha ¥ dumetorum. Figs 41, 45, 47, 49, 52. Colpus shape.
Figs 42, 43, 50, 51, 53. Polar view and high focus. Figs 44, 48. Equatorial view and high focus. Fig. 46. Equatorial view
and low focus. Fig. 54. Polar view and low focus. Scale bars, 10 mm.
heterosyncolpate, prolate-spheroidal to suboblate, of Lamiaceae pollen is often affected by the state of
with a polar axis of 21.53–42.33 mm and an equatorial hydration and/or fixation (Sebsebe & Harley, 1992).
diameter of 20.16–41.27 mm. Of the species investi- The pollen grains in this group frequently undergo a
gated, the largest pollen grains, on average, were dramatic shape change as a result of colpal mem-
observed in M. ¥ dumetorum and the smallest pollen brane loss during acetolysis. As a result of hot acid
grains, on average, were observed in M. suaveolens. treatment, oblate or suboblate grains frequently
The amb shape is circular (Figs 4, 8, 12, 16, 20, 24, 28, become subprolate or prolate, because in the absence
32, 36, 40). It is noteworthy, however, that the shape of the colpal membranes the intercolpal areas of
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146 S. CELENK ET AL.
Figures 55–65. Scanning electron micrographs of pollen grains of Mentha (equatorial view). Fig. 55. M. aquatica. Fig. 56.
M. ¥ dumetorum. Fig. 57. M. longifolia ssp. longifolia. Fig. 58. M. longifolia ssp. typhoides var. typhoides. Fig. 59.
M. ¥ piperita. Fig. 60. M. pulegium. Fig. 61. M. ¥ rotundifolia. Fig. 62. M. spicata ssp. spicata. Fig. 63. M. spicata ssp.
tomentosa. Fig. 64. M. suaveolens. Fig. 65. M. ¥ villosa-nervata. Scale bars, 10 mm.
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PALYNOLOGY OF MENTHA L. (LAMIACEAE) 147
Figures 66–71. Scanning electron micrographs of pollen grains of Mentha (surface details, mesocolpium, and colpus
margin). Fig. 66. M. aquatica. Fig. 67. M. ¥ dumetorum. Fig. 68. M. longifolia ssp. longifolia. Fig. 69. M. longifolia ssp.
typhoides var. typhoides. Fig. 70. M. ¥ piperita. Fig. 71. M. pulegium. Scale bars: Fig. 70, 5 mm; remainder, 2 mm.
the tectum tend to close in (Harley, 1992). In order absent. In the reticulate ornamentation, some of the
to retain the natural form of the pollen grains, the reticulum is subdivided into a few smaller units. The
Wodehouse method was used in our study. average diameter of the small perforations is less
The exine sculpture is bireticulate (section than 1.50 mm. The exine thickness is 0.75–1.56 mm,
Pulegium) or reticulate (section Menthae) (the termi- and the intine thickness is 0.68–1.13 mm.
nology follows Harley et al., 1992). In the bireticulate Cantıno, Harley & Wagstaff (1992) placed the genus
ornamentation, which only distinctly occurs in Mentha into the subfamily Nepetoideae, tribe Men-
M. pulegium, the muri of the primary reticulum are theae. Based on a study of 128 species of this tribe,
shallow and usually rounded or occasionally more or Wagstaff (1992) produced a phylogenetic interpreta-
less polygonal (Figs 66, 70, 71, 74, 76), and the tion of pollen morphology. Our results are a confir-
lumina size is small, the secondary reticulum is finely mation of the concept of the genus position used until
reticulate, with the number of perforations not now. Hexazonocolpate pollen probably represents a
exceeding six per larger lumen of the primary reticu- synapomorphy in this order comprising the subfamily
lum, or the secondary reticulum is more or less Nepetoideae (Cantıno & Sanders, 1986; Abu-Asab &
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148 S. CELENK ET AL.
Figures 72–76. Scanning micrographs of pollen grains of Mentha (surface details, mesocolpium, and colpus margin).
Fig. 72. M. ¥ rotundifolia. Fig. 73. M. spicata ssp. spicata. Fig. 74. M. spicata ssp. tomentosa. Fig. 75. M. suaveolens.
Fig. 76. M. ¥ villosa-nervata. Scale bars, 2 mm.
Cantıno, 1992, 1994); furthermore, pollen with a resentative pollen grains are illustrated in LM and
tectate-perforate to reticulate exine structure and a SEM (Figs 1–76). The tendency towards reduction of
surface ornamented with a network of supratectal the tectum is characteristic of many other genera and
ridges surrounding polygonal lumina is hypothesized species in the tribe Mentheae [for example, Origanum
to be a plesiomorphic condition within the subfamily L. (Husain & Heywood, 1982), Thymbra L. (Morales-
Nepetoideae, where it occurs, for example, in the tribe Valverde, 1987), Micromeria L. (Morales-Valverde,
Mentheae: Perilla L., Elshohzia Willd., Perillula 1990), and Nepeta L. (Celenk, 2006)], and is generally
Maxim., Hyssopus L., Monardella Benth., and interpreted as an evolutionary trend.
Satureja mimoloides Briq. (Wagstaff, 1992). It is char- The ectocolpi are distributed symmetrically, elon-
acteristic of Mentha pollen that it has two different gated, usually shallow, and narrowing at the poles,
exine structures and a surface ornamentation char- except in M. ¥ dumetorum. In all the investigated
acterized by the partial reduction of the tectum. Rep- species, the colpus membrane is finely or coarsely
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PALYNOLOGY OF MENTHA L. (LAMIACEAE) 149
Table 2. Pollen morphological data (mean values, standard deviations, and variations) of Mentha species
Mesocolpium Apocolpium Exine Intine
Taxon Clg Clt thickness diameter thickness thickness
M. aquatica 32.29 ± 2.04 5.43 ± 0.97 11.61 ± 1.11 14.32 ± 1.46 1.52 ± 0.30 1.05 ± 0.20
(25.74–34.26) (3.03–7.14) (8.98–13.1) (11.27–16.39)
M. ¥ dumetorum 32.08 ± 1.89 4.76 ± 1.35 13.16 ± 2.07 6.65 ± 1.55 1.56 ± 0.32 1.05 ± 0.22
(29.05–35.35) (2.78–10.36) (10.17–17.96) (7.41–16.43)
M. longifolia ssp. longifolia 24.73 ± 2.31 4.60 ± 0.76 10.00 ± 1.67 10.61 ± 1.29 1.23 ± 0.27 1.00 ± 0.22
(19.47–27.79) (3.15–6.63) (7.13–12.94) (8.99–13.33)
M. longifolia ssp. typhoides 24.32 ± 2.40 4.50 ± 1.00 12.29 ± 1.93 11.94 ± 0.46 1.40 ± 0.40 1.13 ± 0.26
var. typhoides (21.32–28.66) (3.90–7.55) (9.19–15.93) (11.22–12.53)
M. ¥ piperita 19.78 ± 3.62 4.02 ± 0.58 9.40 ± 4.82 10.22 ± 0.82 1.27 ± 0.19 0.81 ± 0.17
(16.06–27.71) (3.14–5.08) (7.58–11.68) (8.87–11.32)
M. pulegium 22.25 ± 1.11 4.89 ± 2.14 7.65 ± 1.33 7.00 ± 0.48 0.75 ± 0.10 0.68 ± 0.08
(16.83–23.04) (3.30–9.83) (6.07–9.73) (5.47–7.54)
M. ¥ rotundifolia 20.95 ± 2.94 3.69 ± 0.86 8.54 ± 0.95 9.49 ± 1.07 1.16 ± 0.16 0.77 ± 0.18
(16.01–25.51) (2.14–6.23) (6.91–11.43) (8.30–11.30)
M. spicata ssp. spicata 24.51 ± 3.64 3.65 ± 0.78 10.99 ± 1.63 11.35 ± 0.66 1.43 ± 0.29 1.12 ± 0.33
(21.51–30.17) (2.61–5.34) (8.28–13.17) (10.26–12.27)
M. spicata ssp. tomentosa 25.21 ± 6.44 3.68 ± 1.04 10.42 ± 2.55 12.06 ± 1.83 1.23 ± 0.24 1.08 ± 0.23
(15.21–32.48) (1.98–5.13) (9.43–10.77) (9.87–10.64)
M. suaveolens 18.19 ± 0.77 3.11 ± 1.40 6.17 ± 1.04 9.85 ± 1.19 1.18 ± 0.29 0.87 ± 0.11
(17.24–24.43) (1.16–5.02) (4.85–7.43) (8.09–11.12)
M. ¥ villosa-nervata 21.14 ± 3.20 4.07 ± 0.71 8.79 ± 1.67 8.77 ± 1.19 1.29 ± 0.34 0.85 ± 0.13
(15.10–25.85) (2.94–5.74) (9.50–10.16) (9.59–11.15)
Clg, colpus length; Clt, colpus width. All measurements in mm.
Table 3. Pollen morphological data of Mentha L. species
Taxon MN Mesh diameter (mm) Sculpture
M. aquatica 1–3 0.40–1.40 Reticulate
M. ¥ dumetorum 3–4 0.20–1.85 Reticulate
M. longifolia ssp. longifolia 3–5 0.20–0.85 Reticulate
M. longifolia ssp. typhoides var. typhoides 2–5 0.20–0.90 Reticulate
M. ¥ piperita 1–5 0.10–1.40 Reticulate
M. pulegium 4–7 0.20–0.80 Bireticulate
M. ¥ rotundifolia 2–6 0.10–1.20 Reticulate
M. spicata ssp. spicata 1–3 0.20–1.20 Reticulate
M. spicata ssp. tomentosa 1–3 0.25–1.20 Reticulate
M. suaveolens 4–5 0.15–0.85 Reticulate
M. ¥ villosa-nervata 4–7 0.15–0.80 Reticulate
MN, mesh number in 2 mm2.
granular, visible in LM (for example, Figs 1, 5, 9, 13, pate to c. 60% for hexacolpate. In half (c. 50%) of the
17, 21, 25, 29, 33, 37, 42). The range of colpus length hexacolpate pollen grains, the colpi present a round
of all the studied taxa is 18.19–32.29 mm (Table 1). amb with three large and three slightly smaller meso-
The length of the colpus is not correlated with the colpia (Figs 44, 48, 51, 53), like many hexacolpate
whole pollen size. The range of colpus width of all Lamiaceae pollen grains, as discussed by Pozhidaev
the studied taxa is 3.11–5.43 mm (Table 1). In (1992).
M. ¥ dumetorum, different colpus shapes were recog- The ranges of the mesocolpial area and apocolpium
nized (Figs 41–54). The colpi of pollen grains in diameter of the studied taxa are 6.17–13.16 mm and
M. ¥ dumetorum varied from c. 40% for heterosyncol- 6.65–14.32 mm, respectively. All palynological data
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150 S. CELENK ET AL.
Table 4. Results of analysis of variance (ANOVA) for the characters studied in Mentha L. pollen grains
Polar axis Equatorial axis
Analysed level F-ratio d.f. s.l. F-ratio d.f. s.l.
Amongst all taxa 171.26 10 * 112.40 10 *
237 248
Amongst ploidy levels 78.00 2 * 53.43 2 *
(2n = 20, 24, 36, 48–96) 245 256
d.f., degrees of freedom; s.l., significance level.
*Significant at 0.005.
45
35
25
15
Figure 77. Maximum, minimum, and average size of polar axis (P) of Mentha species.
of the investigated Mentha species are given in grains is obvious. The smallest pollen grains are
Tables 1–3. found in M. suaveolens (section Menthae), with a chro-
The genus Mentha is taxonomically complex and mosome number of 2n = 24. This species is part of an
characterized by a high level of reticulate evolution. individual ploidy line with a basic chromosome
Only a few, frequently overlapping, characters are of number of x = 12. The largest pollen grains are found
value in taxonomy. Pollen data were evaluated sta- in M. ¥ dumetorum (tetraploid with 2n = 60) (Figs 77,
tistically to ascertain the value of pollen characters in 78). The tendency to larger pollen grains with an
the taxonomy of Mentha (Tables 4 and 5). The results increase in chromosome number has also been
of ANOVA and Scheffe’s range tests allow the selec- described in the genus Thymus L. (Lamiaceae) by
tion of homogeneous groups within the data set Martonfi (1997).
analysed. Results from ANOVA tests show statisti- The pollen grain sizes obtained were compared with
cally significant differences both amongst samples of a few previously published data. Jancic & Polic (1989)
the same species and amongst samples with different reported the following pollen sizes: M. aquatica,
chromosome numbers. Scheffe’s test clearly shows P = 37.71, 35.29 mm, E = 27.90, 26.57 mm; M. spicata
that there are three different groups on the basis of ssp. tomentosa, P = 36.96, 38.84 mm, E = 25.96,
polar axis size and two different groups on the basis 28.87 mm; M. pulegium, P = 30.79 mm, E = 17.82 mm.
of equatorial diameter in the data set studied, and, Perveen & Qaiser (2003) reported the following
furthermore, that these groups correspond to chromo- pollen sizes: M. longifolia, P = 29.11 mm, E = 28.29 mm;
some number (Tables 4 and 5). With an increase in M. spicata, P = 27.50 mm, E = 25.70 mm. Gocmen et al.
chromosome number, the tendency to larger pollen (1997) provided brief pollen data of six Mentha taxa
© 2008 Uludag University. Journal compilation
© 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 141–154
suaveolens
pulegium
rotundifolia
piperita
villosa-nervata
longifolia ssp.
longifolia
spicata ssp.
tomentosa
spicata ssp.
spicata
longifolia ssp.
typhoides
aquatica
dumetorum
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PALYNOLOGY OF MENTHA L. (LAMIACEAE) 151
© 2008 Uludag University. Journal compilation
© 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 141–154
Table 5. Mean and results of Scheffe’s test for P and E in Mentha L. pollen grains
Polar axis Scheffe’s test Equatorial axis Scheffe’s test
2n Taxon (mean in mm) (P < 0.05) 2n Taxon (mean in mm) (P < 0.05)
24 M. suaveolens 21.53 1 24 M. suaveolens 20.16 1
20 M. pulegium 23.47 1 2 24 M. ¥ rotundifolia 24.27 1 2
24 M. ¥ rotundifolia 23.66 1 2 20 M. pulegium 25.14 1 2 3
36 M. ¥ villosa-nervata 26.90 2 3 36 M. ¥ villosa-nervata 25.72 2 3
72 M. ¥ piperita 26.97 2 3 72 M. ¥ piperita 29.35 3 4
48 M. spicata ssp. 29.02 3 24 M. longifolia ssp. 30.82 4
tomentosa longifolia
48 M. spicata ssp. 30.01 3 48 M. spicata ssp. 31.08 4
spicata spicata
24 M. longifolia ssp. 30.11 3 48 M. spicata ssp. 31.67 4
longifolia tomentosa
24 M. longifolia ssp. 31.02 3 24 M. longifoiai ssp. 34.05 4
typhoides typhoides
var. typhoides var. typhoides
96 M. aquatica 39.58 4 96 M. aquatica 39.56 5
60 M. ¥ dumetorum 42.33 4 60 M. ¥ dumetorum 41.27 5
Chromosome number Chromosome number
2n = 20–24 26.97 I 2n = 20–24 28.65 I
2n = 36–48 29.61 II 2n = 36–48 31.08 I
2n = 60–96 36.18 III 2n = 60–96 36.04 II
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152 S. CELENK ET AL.
45
35
25
15
Figure 78. Maximum, minimum, and average size of equatorial axis (E) of Mentha species.
using LM. Most of the taxa investigated by Gocmen ACKNOWLEDGEMENTS
et al. (1997) had more or less similar pollen morpholo-
gies to those examined by us, except for the differences This research was supported by Uludag University
in size, ratio of the polar axis to equatorial diameter, Research Foundation Centre (project number F-2003/
and sculpture types. The values are a little different 3).
from those given in the present paper. It is possible
that the slight variation is a result of differences in
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APPENDIX
SPECIMENS EXAMINED
Taxon Locality (from Turkey)
Mentha aquatica 1. A1: Kirklareli; Babaeski, Mimar Sinan bridge, streambed, 60 m, 23.viii.2003,
G. Tarimcilar
2. Balikesir; Balya way-out, Balikesir to Ivrindi crossroads, 40 km below
Balikesir, watery places, 280 m, 26.viii.2004, G. Tarimcilar
Mentha ¥ dumetorum A1: Kirklareli; Babaeski, Mimar Sinan bridge, streambed, 60 m, 23.viii.2003,
G. Tarimcilar
Mentha longifolia ssp. longifolia A1: Kirkpinar, 4 km above İnece, waterway sides, 160 m, Typha sp., 23.viii.2003,
G. Tarimcilar
Mentha longifolia ssp. Balikesir; Balya way-out, Balikesir to İvrindi crossroads, 40 km below Balikesir,
typhoides var. typhoides watery places, 280 m, 26.viii.2004, G. Tarimcilar
Mentha ¥ piperita Istanbul, Sile-Omerli, dam way, road side, grassland, 15.viii.2005 G. Tarimcilar
© 2008 Uludag University. Journal compilation
© 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 141–154
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154 S. CELENK ET AL.
APPENDIX Continued
Taxon Locality (from Turkey)
Mentha pulegium A2: Istanbul; Catalca, 15.ix.2003, H. Malyer
B2: Balikesir; Bandirma, Manyas Kus cenneti, lake sides, 190 m, 27.viii.2004,
G. Tarimcilar
Mentha ¥ rotundifolia B2: Balikesir; Bandirma to Erdek, Duzler way-out, grassland, 130 m,
27.viii.2004, G. Tarimcilar
Mentha spicata ssp. spicata A1: Kirklareli; 22 km below Kirklareli, Urunlu village, stream sides, 120 m,
23.viii.2003, G. Tarimcilar
Mentha spicata ssp. tomentosa A1: Edirne; Edirne to Istanbul, 15 km below Ogulpasa village, damp places,
70 m, 23.viii.2003, G. Tarimcilar
B1: Canakkale; Bayramic, 2 km below Cırpıcılar, stream sides, Juncus sp.,
350 m,
26.viii.2004, G. Tarimcilar
Mentha suaveolens A2: Bursa; Gorukle, Uludag University, campus, 155 m, 30.viii.1992,
G. Tarimcilar
Mentha ¥ villosa-nervata A1: Canakkale; Saros bay, Kocacesme village, streambed that dries up in
summer, 35 m, 25.viii.2004, G. Tarimcilar
A1: Canakkale; Lapseki to Beycayiri, Sahinli village, road sides, dry places,
220 m, 25.viii.2004, G. Tarimcilar
© 2008 Uludag University. Journal compilation
© 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157, 141–154
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