Embryology of two mycoheterotrophic orchid species, Gastrodia elata and Gastrodia nantoensis: ovule and embryo development

Botanical Studies

Table 2 Changes in cell dimensions during embryo sac development of G. elata and G. nantoensis

Developmental stage	Taxon	X-axis^a	Y-axis^a
Megasporocyte	G. elata	21.7 ± 0.7	29.4 ± 1.3
Megasporocyte	G. nantoensis	20.4 ± 0.6	29.1 ± 1.5
Functional dyad	G. elata	20.8 ± 1.0	26.6 ± 1.7
Functional dyad	G. nantoensis	20.5 ± 0.8	28.7 ± 1.1
2-nucleate embryo sac	G. elata	25.1 ± 1.7	35.7 ± 2.5
2-nucleate embryo sac	G. nantoensis	26.4 ± 1.1	36.1 ± 2.2
4-nucleate embryo sac	G. elata	28.5 ± 1.2	42.8 ± 1.8
4-nucleate embryo sac	G. nantoensis	27.3 ± 1.7	44.6 ± 2.6
Mature embryo sac	G. elata	31.0 ± 1.1	53.1 ± 2.4
Mature embryo sac	G. nantoensis	31.7 ± 1.5	54.6 ± 1.9