Peculiarities of the reproductive biology of three species of genus Colchicum from Bulgaria

Figures & data

Table 1. Origin of plant material.

Species	Floristic region/population	Coordinates	Altitude in m	Climate region
Colchicum autumnale L.	Balkan mountain range (Western part)/Balyuvitsa	N43029’897’’ E23020’117’’ʺ	270	European Continental Climatic Zone.
Colchicum bivonae Guss.	Struma valley	N41046’765’’, E23009’231’’,	142	Mediterranean climate zone
Colchicum Diampolis Delip. & Cheshm.	Tundzha hilly valley/Near the town of Yambol	N42528’18’’ E26520’55’’	134	European Continental Climatic Zone
	Tundzha hilly valley/Near the town of Karnobat	N42651’110’’, Е26980’350’’	204

Table 2. Pollen viability in studied species, analysed by acetocarmine staining.

Species	Population	Number of pollen grains analysed	Viability (%±SD)
C. autumnale	Berkovitsa	2289	85.33 ± 5.814
C. diampolis	Karnobat	2040	91.84 ± 2.392
C. diampolis	Yambol	2739	94.86 ± 4.43
C. bivonae	Kresna	3399	89.73 ± 4.564

Figure 1. Development of male gametophyte and estimation of pollen viability by acetocarmine testing: (a) mature pollen and anther wall; (b) two-celled mature pollen grains; (c) viable pollen grains; (d) nonviable pollen grain. Abbreviations: pg, pollen grain; ep, epiderma; en, endotecium; ml middle layer. Magnification: 400×.

Figure 2. Ovule and development of female gametophyte: (a) three-locular ovary; (b) mature embryo sac with nucellar cap and integumental tapetum and egg apparatus; (c) egg apparatus and two polar nuclei in the mature embryo sac; (d) egg apparatus and central cell in the mature embryo sac. Abbreviations: hyp, hypostase; it, integumental tapetum; nc, nucellar cap; pn, pollar nucleus; cc, central cell; egc, egg cell; sin, synergid. Magnification: 100× for (a), 400× for (b–d).

Figure 3. Ovule and development of female gametophyte: (a) two celled proembryo and endospermal nuclei; (b) young Asterad-type embryo in the embryo sac; (c) globular embryo; (d) mature embryo sac with podium, hypostase and egg cell, antipodals and additional synergid embryo. Abbreviations: egc, egg cell; ant, antipodal; em, embryo; endn, еndospermal nucleus; hyp, hypostase. Magnification 400×.

Figure 4. Ovule and development of female gametophyte: (a) anatropous ovule in the ovary locule; (b) mature embryo sac with integumental tapetum and legitimate, additional embryo and antipodals (c) integumental obturator; (d) two embryos – legitimate and additional at globular stage. Abbreviations: ao, anatropous ovule; io, integumental obturator; it, integumental tapetum; ant, antipodal; lem, legitimate embryo; adem, additional embryo; intint, internal integument; exint, external integument. Magnification: 100x for fig. (a), 400x for figs (b)-(d).

Figure 5. Seed viability according tetrazolium test: (a) dark red coloured viable embryo; (b) dark red coloured viable embryo with part of endosperm; (c) light red coloured viable embryo; (d) nonviable colourless embryo. Abbreviations: cot, cotyledon; end, endosperm; rt, root tip.

Figure 6. Frequency of embryos in classes depending on the stainability in the three studied species: Class I – dark red coloured embryos; Class II – light red coloured embryos; Class III – stainless embryos; 1. C. autumnale; 2. C. diampolis – population from Karnobat; 3. C. diampolis – population from Yambol; 4. C. bivonae.