Abstract
In the present work, we study the ovule, seed, and fruit development in six Bulbostylis species in order to characterize the genus in a comparative approach and to identify the characteristics that can be used in taxonomy and phylogeny. Flowers and fruits at different developmental stages were analyzed using LM and SEM after processing according to standard techniques. The species studied have the following: anatropous and bitegmic ovules, weak crassinucellar ovules, obturator of integumentary origin, monosporic embryo sac of the Polygonum type, nuclear endosperm, hypostase formation, seed coat formed by tanniferous endotegmen and exotesta, and Bulbostylis-type embryo. On the other hand, the pericarp development constitutes the main variation within Bulbostylis since the cells of the exocarp may or may not present starch grains, and their inner periclinal walls may be slightly or deeply concave depending on the degree of development of the mesocarp sclereids. In a taxonomic context, the results herein obtained are in conflict with studies which suggest infrageneric groupings based on fruit micromorphology, and also with the relationship among the Bulbostylis species based on molecular analysis. This work contributes to a better understanding of the reproductive anatomy and embryology in Bulbostylis, and reveals the first insights about the origin of multiple embryos in Cyperaceae. Given the frequent presence of polyembryony in Bulbostylis, and the poor mention of this condition in the family, this work highlights an aspect in the anatomy of Cyperaceae that must be re-explored.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Barros M (1947) Cyperaceae. In: Descole H (ed) Genera et Species Plantarum Argentinarum. Guillermo Kraft, Buenos Aires, pp 273–297
Boesewinkel FD, Bouman F (1995) The seed: structure and function. In: Kigel J, Galili G (eds) Seed Development and Germination. Marcel Dekker, New York, pp 1–24
Caetano APS, Teixeira SP, Forni-Martins ER, Carmello-Guerreiro SM (2013) Pollen insights into apomictic and sexual Miconia (Miconieae, Melastomataceae). Int J Plant Sci 174:760–768. https://doi.org/10.1086/669927
Caetano APS, Cortez PA (2014) Reprodução assexuada. In: Rech AR, Agostini K, Oliveira PE, Machado IC (eds) Biologia da Polinização. Editora Projeto Cultural, Rio de Janeiro, pp 93–111
Coan AI, Alves MV, Scatena VL (2008) Comparative study of ovule and fruit development in species of Hypolytrum and Rhynchospora (Cyperaceae, Poales). Pl Syst Evol 272:181–195. https://doi.org/10.1007/s00606-007-0636-9
Cortez PA, Carmello-Guerreiro SM, Teixeira SP (2012) Understanding male sterility in Miconia species (Melastomataceae): a morphological approach. Aust J Bot 60:506–516. https://doi.org/10.1071/BT12076
Endress PK, Baas P, Gregory M (2000) Systematic plant morphology and anatomy-50 years of progress. Taxon 49:401–434. https://doi.org/10.2307/1224342
Endress PK (2011) Angiosperm ovules: diversity, development, evolution. Ann Bot 107:1465–1489. https://doi.org/10.1093/aob/mcr120
Givnish TJ, Zuluaga A, Spalink D, Soto Gomez M, Lam VKY, Saarela JM, Sass C et al (2018) Monocot plastid phylogenomics, timeline, net rates of species diversification, the power of multi-gene analyses, and a functional model for the origin of monocots. Am J Bot 105:1888–1910. https://doi.org/10.1002/ajb2.1178
Goetghebeur P (1998) Cyperaceae. In: Kubitzki K (ed) The families and genera of vascular plants, vol 4. Springer-Verlag, Berlin, pp 141–190
Goetghebeur P, Coudijzer J (1985) Studies in Cyperaceae 5. The Genus Bulbostylis in Central Africa. Bull Jard Bot Belg 55:207–259. https://doi.org/10.2307/3668016
Gonzalez AM, López MG (2010) Development and morphology of the gynoecium and nutlet in two South-American Bulbostylis (Cyperaceae) species. Flora 205:211–220. https://doi.org/10.1016/j.flora.2009.02.002
Govaerts R, Jimenez-Mejias P, Koopman J, Simpson D, Goetghebeur P, Wilson K, Egorova T, Bruhl J (2020) World checklist of Cyperaceae. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet http://wcsp.science.kew.org/. Accessed 30 Jan 2020
Johansen DA (1940) Plant microtechnique. McGraw-Hill Book Co, New York
Johri BM, Ambegaokar KB, Srivastava PS (1992) Comparative embryology of angiosperms, vol 2. Springer-Verlag, Berlin, pp 974–981
Juguet M (1967) Polyembryonie chez le Kobresia bellardii (All.) Degld. Bull Soc Bot Fr 114:7–8, 277–279. https://doi.org/10.1080/00378941.1967.10838360
Kellogg EA (2015) Embryology. In: Kubitzki K (ed) Flowering Plants. Monocots. The Families and Genera of Vascular Plants, vol 13. Springer, Cham, pp 45–53. https://doi.org/10.1007/978-3-319-15332-2_4
Kern JH (1974) Cyperaceae. In: van Steenis CGGJ (ed) Flora Malesiana I, Noordhoff International Publishing, Leiden, pp 7:107–187
Khanna P (1965) A contribution to the embryology of Cyperus rotundus L., Scirpus mucrinatus L., and Kyllinga melanospora Nees. Can J Bot 43:1539–1547. https://doi.org/10.1139/b65-163
Kral R (1971) A treatment of Abildgaardia, Bulbostylis and Fimbristylis (Cyperaceae) for North America. Sida 4:57–227
López MG (2012) Citología, morfología y taxonomía del género Bulbostylis (Cyperaceae) para América Austral. Ph Thesis, Universidad Nacional del Nordeste, Corrientes, Argentina
López MG, Gonzalez AM (2017) Micromorfología y estructura de los frutos en Bulbostylis (Cyperaceae) y su valor sistemático en las especies de América Austral. Bol Soc Argent Bot 52:69–87. https://doi.org/10.31055/1851.2372.v52.n1.16909
Luque R, Sousa HC, Kraus JE (1996) Métodos de coloração de Roeser (1972) -modificado- e Kropp (1972) visando a substituição do azul de astra por azul de alcião 8 GS ou 8GX. Acta Bot Bras 10:199–212. https://doi.org/10.1590/S0102-33061996000200001
Maheshwari P (1950) An introduction to the embryology of angiosperms. McGraw-Hill, New York
Makde KH, Bhuskute SM (1987) Embryology of Kyllinga monocephala (Cyperaceae) and its systematic position. Plant Syst Evol 156:143–150. https://doi.org/10.1007/BF00936069
Metcalfe CR (1971) Anatomy of the monocotyledons: V. Cyperaceae. Oxford University Press, Oxford
Murty YS, Kumar V (1967) Development of the female gametophyte and embryo in Fimbristylis diphylla Vahl. Proc Indian Acad Sci 65B:185–191. https://doi.org/10.1007/BF03052209
Nagaraj M, Nijalingappa BHM (1973) Embryological studies in Cyperus alopecuroides Rottb. Proc Indian Acad Sci 77B:252–263. https://doi.org/10.1007/BF03045598
Nijalingappa BHM (1976) Sporogenesis and gametogenesis in some Cyperaceae. Proc Indian Acad Sci 83:66–72
Nijalingappa BHM (1977) Post-pollination studies in some Cyperaceae. Proc Indian Acad Sci 85:391–398. https://doi.org/10.1007/BF03052247
Nijalingappa BHM (1986) Embryology of Scleria foliosa (Cyperaceae). Plant Syst Evol 152:219–230. https://doi.org/10.1007/BF00989429
Nijalingappa BHM, Palakshaiah CR (1998) Embryological studies in Rhynchospora wightiana (Cyperaceae). In: BhatiaShukla BAK, Sharma HL (eds) Plant Form and Function. Angkor Publishers, New Delhi, pp 225–236
Oriani A, Scatena VL (2012) Floral anatomy of Xyrids (Poales): contributions to their reproductive biology, taxonomy, and phylogeny. Int J Plant Sci 173:767–779. https://doi.org/10.1086/666664
Ornduff R (1978) Reproductive characters and taxonomy. Syst Bot 3:420–427. https://doi.org/10.2307/2418754
Padhye MD (1960) A contribution to the life history of Kyllinga triceps Rottb. Bot Soc Coll Sci, Nagpur, Bull 1:1–15
Padhye MD (1968) Male and female gametophytes of Eleocharis geniculata Roem. et Schult. Proc Indian Acad Sci 67B:54–60. https://www.ias.ac.in/article/fulltext/secb/067/02/0054-0060
Padhye MD (1971) Studies in Cyperaceae. III. Life history of Kyllinga brevifolia Rottb. with a brief discussion on systematic position of Kyllinga. Bot Gaz 132: 172–179. https://www.jstor.org/stable/2474090
Padhye MD, Kasture SW (1970) Studies in Cyperaceae. V. Gametophytes and fertilization in Pycreus globossus (All.) var. niligiricus (Stead) CBCl. J Biol Sci 13:37–42
Padhye MD, Makde KH (1982) Embryogeny in some Cypereae. Plant Syst Evol 139:279–287. https://doi.org/10.1007/BF00989330
Padhye MD, Chaube SN, Iyer AV (1970) Studies in Cyperaceae. VIII. Gametophytes and fertilization in two members of Cyperaceae. J Indian Bot Soc 49:86–91
Pedersen TM (1969) Cyperaceae. In: Cabrera AL (ed) Flora de la Provincia de Buenos Aires. Colección Científica del INTA, Buenos Aires, pp 315–421
Reutemann AG, Lucero LE, Guarise NJ, Vegetti AC (2012) Structure of the Cyperaceae inflorescence. Bot Rev 78:184–204. https://doi.org/10.1007/s12229-012-9098-z
Reutemann AG, Ardissone RE, López MG, Muchut S, Boldrini I, Vegetti AC, Giussani L (2018) Phylogenetic relationships in Bulbostylis (Cyperaceae: Abildgaardieae) inferred from nuclear and plastid DNA sequence data. System Biodivers 16:441–452. https://doi.org/10.1080/14772000.2018.1442885
Reynders M, Vrijdaghs A, Larridon I, Huygh W, Leroux O, Muasya M, Goetghebeur P (2012) Gynoecial anatomy and development in Cyperoideae (Cyperaceae, Poales): congenital fusion of carpels facilitates evolutionary modifications in pistil structure. Plant Ecol Evol 145:96–125. https://doi.org/10.5091/plecevo.2012.675
Rocha DM, Andrade CGTJ, Vanzela ALL (2015) Female gametophyte development in Eleocharis sellowiana (Cyperaceae): a species with atypical nuclear staining and polarity of the megaspore mother cell. Plant Syst Evol 301:1287–1292. https://doi.org/10.1007/s00606-014-1145-2
Rudall PJ (1997) The Nucellus and Chalaza in monocotyledons: structure and systematics. Bot Rev 63:140–181. https://doi.org/10.1007/BF02935930
Ruzin SE (1999) Plant microtechnique and microscopy. Oxford University Press, New York
Semmouri I, Bauters K, Léveillé-Bourret É, Starr JR, Goetghebeur P, Larridon I (2019) Phylogeny and systematics of Cyperaceae, the evolution and importance of embryo morphology. Bot Rev 85:1–39. https://doi.org/10.1007/s12229-018-9202-0
Shah CK (1965) Embryogeny in some Cyperaceae. Phytomorphology 15:1–9
Shah CK (1967) A taxonomical evaluation of the families Cyperaceae and Juncaceae. Symp Newer Trends in Taxonomy. Nat Inst Sci India, New Delhi 34:248–256
Singh V (1981) Taxonomy of angiosperms. Rastogi Publications, New Delhi
Svenson HK (1957) Poales-Cyperaceae. North American. Flora 18:540–556
Tiwari DK (1969) Embryological studies in the Cyperaceae. A contribution to the embryology of Pycreus sanguinolentus Nees. J Biol Sci 12:21–30
Tobe H (1989) The embryology of angiosperms: its broad application to the systematic and evolutionary study. Bot Mag Tokyo 102:351–367. https://doi.org/10.1007/BF02488572
Van der Veken P (1965) Contribution a l’embryographie systématique des Cyperaceae-Cyperoideae. Bulletin du Jardin botanique de l’État a Bruxelles 35:285–354. https://www.jstor.org/stable/3667185
Vrijdaghs A, Muasya AM, Goetghebeur P, Caris P, Nagels A, Smets E (2009) A floral ontogenetic approach to questions of homology within the Cyperoideae (Cyperaceae). Bot Rev 75:30–51. https://doi.org/10.1007/s12229-008-9021-9
Acknowledgements
The authors are grateful to the staff of Bernardino Rivadavia Museum (Buenos Aires, Argentina) for their technical assistance during SEM sessions. We are also grateful to the anonymous reviewers whose comments and suggestions were helpful in improving the manuscript.
Funding
This work was supported by the Agencia Nacional de Promoción Científica y Tecnológica, Argentina (PICT 2013–0473 to A.R., and PICT 2019–01678 to A.R.), and Universidad Nacional del Litoral, Santa Fe, Argentina (CAI + D2020-50520190100078LI to A.R.).
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Ethics approval and consent to participate
Ethics approval not applicable.
All authors have seen and agree with the content of this manuscript.
Consent for publication
All authors agree with the publication of this manuscript.
Conflict of interest
The authors declare no competing interests.
Additional information
Handling Editor: Dorota Kwiatkowska.
Publisher's note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
709_2021_1649_MOESM1_ESM.pdf
Supplementary file1 Megasporogenesis and megagametogenesis in Bulbostylis communis, in longitudinal sections. (A-D) megasporocyte formation (E) megaspores dyad (F) megaspores tetrad (G-J) successive stages of megagametophyte formation (K) and (L) mature megagametophyte, where the fusion of both polar nuclei has already occurred. Abbreviations: ac archesporial cell, c carpel, ch chalaza, chp chalazal pole, dc dyad cells, dm degenerate megaspores, f funiculus, fm functional megaspore, ii inner integument, m micropyle, mc megasporocyte, mp micropylar pole, n nucellus, o ovule, ob obturator, oi outer integument, ov ovary wall, s embryo sac, te megaspores tetrad. Scale bars: A, B, D-J, L = 10 µm; C, K = 50 µm (PDF 9106 KB)
709_2021_1649_MOESM2_ESM.pdf
Supplementary file2 Embryogenesis and endospermogenesis in Bulbostylis communis, in longitudinal sections. (A-B) zygote, and endosperm with a few free nuclei (C) endosperm after some free-nuclear divisions and detail of the hypostase in the chalazal region (D) and (E) embryo after the first division of the zygote (F) and (G) embryo at globular stage, and nuclear endosperm; the obturator is observed in the micropylar region (H) globular embryo at later stage of development, and endosperm cellularization (I-M) mature seed with mature embryo, and endosperm. Abbreviations: chp chalazal pole, e embryo, ed endosperm, hy hypostasis, mp micropylar pole, n nucellus, ob obturator, pe pericarp, tg tegmen, ts testa, z zygote. Scale bars: A, C-M = 50 µm; B = 10 µm (PDF 283 KB)
709_2021_1649_MOESM3_ESM.pdf
Supplementary file3 Megasporogenesis and megagametogenesis in Bulbostylis juncoides, in longitudinal sections. (A) megasporocyte stage (B) megaspores tetrad with the three micropylar megaspores degenerating (C) chalazal megaspore before mitotic division (D) early stage of the megagametophyte formation (E-I) mature megagametophyte (J) and (K) megagametophyte immediately after triple fusion and syngamy. Abbreviations: chp chalazal pole, em endosperm mother cell, fm functional megaspore, ii inner integument, mc megasporocyte, mp micropylar pole, n nucellus, oi outer integument, ov ovary wall, pe pericarp, s embryo sac, te megaspores tetrad, tg tegmen, ts testa, z zygote. Scale bars = 10 µm (PDF 7922 KB)
709_2021_1649_MOESM4_ESM.pdf
Supplementary file4 Embryogenesis and endospermogenesis in Bulbostylis juncoides, in longitudinal sections. (A-D) early stages of embryo and endosperm formation (E-K) successive stages of globular embryo and nuclear endosperm maturation; notice the development of several apomictic embryos (L) and (M) early stage of seed development where only sexual embryo occurs (N) mature seed with mature embryo, and endosperm with polygonal reserve cells. Abbreviations: e embryo, ed endosperm, em endosperm mother cell, n nucellus, ob obturator, pe pericarp, se seed, tg tegmen, ts testa. Scale bars: A, E, H, L, N = 100 µm; B-D, F, G, I-K, M = 10 µm (PDF 6448 KB)
709_2021_1649_MOESM5_ESM.pdf
Supplementary file5 Megasporogenesis, megagametogenesis, embryogenesis, and endospermogenesis in Bulbostylis conifera, in longitudinal sections. (A-C) megasporocyte formation (D-G) megaspores tetrad with the three micropylar megaspores degenerating, and the chalazal one enlarged (H) and (I) mature megagametophyte, where the fusion of both polar nuclei occurred (J) and (K) megagametophyte after triple fusion and syngamy (L) and (M) general view of the seed in the fruit (N) free-nuclear endosperm (O) seed and fruit at later stages of development. Abbreviations: c carpel, ch chalaza, chp chalazal pole, dm degenerate megaspores, e embryo, ed endosperm, em endosperm mother cell, f funiculus, fm functional megaspore, hy hypostasis, ii inner integument, mc megasporocyte, n nucellus, o ovule, oi outer integument, ov ovary wall, pe pericarp, s embryo sac, se seed, te megaspores tetrad, tg tegmen, ts testa, z zygote. Scale bars: A-C, E, F, H, I, K, N = 10 µm; D and G = 50 µm; J, L, M, O = 100 µm (PDF 6199 KB)
709_2021_1649_MOESM6_ESM.pdf
Supplementary file6 Megasporogenesis and megagametogenesis in Bulbostylis hirtella, in longitudinal sections. (A-D) successive stages of megasporocyte formation (E-H) megaspores tetrad with the three micropylar megaspores degenerating (I) early stage of the megagametophyte (J-L) mature megagametophyte. Abbreviations: ac archesporial cell, c carpel, ch chalaza, dm degenerate megaspores, e egg cell, f funiculus, fm functional megaspore, ii inner integument, mc megasporocyte, mp micropylar pole, n nucellus, o ovule, ob obturator, oi outer integument, ov ovary wall, s embryo sac, sy synergid cell, te megaspores tetrad. Scale bars: A-D, F, H, I, K, L = 10 µm; E, G, J = 50 µm (PDF 7058 KB)
709_2021_1649_MOESM7_ESM.pdf
Supplementary file7 Embryogenesis and endospermogenesis in Bulbostylis hirtella, in longitudinal sections. (A) and (B) embryo after the first division of the zygote (C) free-nuclear endosperm, and detail of the hypostase in the chalazal region (D) and (E) successive stages of globular embryo maturation (F) and (G) mature seed with mature embryo, and endosperm with polygonal cells (H) mature endosperm, and detail of the hypostase in the chalazal region. Abbreviations: e embryo, ed endosperm, hy hypostasis, n nucellus, pe pericarp, tg tegmen, ts testa. Scale bars: A, C-H = 50 µm; B = 10 µm (PDF 280 KB)
709_2021_1649_MOESM8_ESM.pdf
Supplementary file8 Megasporogenesis and megagametogenesis in Bulbostylis brevifolia, in longitudinal sections. (A-F) successive stages of megasporocyte formation (G) megaspores dyad (H) megaspores tetrad (I) and (J) early stage of the megagametophyte (K-O) mature megagametophyte. Abbreviations: ac archesporial cell, an antipodal cell, c carpel, ch chalaza, dc dyad cells, f funiculus, ii inner integument, mc megasporocyte, m micropyle, n nucellus, o ovule, oi outer integument, ov ovary wall, s embryo sac, te megaspores tetrad. Scale bars: A-C, E, G, H, J, K = 10 µm; D, F, I, L-N, O = 50 µm (PDF 4741 KB)
709_2021_1649_MOESM9_ESM.pdf
Supplementary file9 Embryogenesis and endospermogenesis in Bulbostylis brevifolia, in longitudinal sections. (A-G) megagametophyte immediately after triple fusion and syngamy (H) mature seed, endosperm and hypostase are observed. (I) mature fruit and seed; endosperm, embryo, hypostase, and pericarp are observed (J) detail of mature pericarp (K) and (L) mature embryo. Abbreviations: ch chalaza, e embryo, ea egg apparatus, ed endosperm, em endosperm mother cell, hy hypostasis, n nucellus, pe pericarp, s embryo sac, tg tegmen, ts testa, z zygote. Scale bars: A, C, E, G, H, J, L = 50 µm; B, D, F = 10 µm; I, K = 100 µm (PDF 245 KB)
709_2021_1649_MOESM10_ESM.pdf
Supplementary file10 Megasporogenesis, megagametogenesis, embryogenesis, and endospermogenesis in Bulbostylis wanderleyana, in longitudinal sections. (A) megasporocyte (B) and (C) mature megagametophyte (D) and (E) seed initiation showing the zygote and the primary endosperm nucleus (F-I) early stage of embryo and nuclear endosperm formation; notice the presence of polyembryony (J) Detail of two embryos in the micropylar region (K) Pericarp in differentiation (L) and (M) four globular embryos (N) Detail of mature pericarp (O) and (P) mature seed with mature embryo and endosperm. Abbreviations: c carpel, ch chalaza, e embryo, ed endosperm, em endosperm mother cell, f funiculus, hy hypostasis, ii inner integument, mc megasporocyte, mp micropylar pole, n nucellus, o ovule, ob obturator, oi outer integument, ov ovary wall, pe pericarp, s embryo sac, se seed, tg tegmen, z zygote. Scale bars: A, D, H, J = 10 µm; B, L, P = 100 µm; C, E-G, I, K, M-O = 50 µm (PDF 5354 KB)
Rights and permissions
About this article
Cite this article
Reutemann, A.G., Muchut, S.E., Manassero, N.G.U. et al. A comparative approach to understanding the ovule, seed, and fruit development in Bulbostylis (Cyperaceae: Cyperoideae: Abildgaardieae). Protoplasma 259, 141–153 (2022). https://doi.org/10.1007/s00709-021-01649-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00709-021-01649-7