Morphology, anatomy and reproduction in Funaria

Morphology, anatomy and reproduction in Funaria

1. Morphological, anatomical and reproductive character in Funaria Sankrita Gaonkar Assistant Professor in Botany [email protected]

2. Contents Morphological, anatomical and reproductive character in Funaria References

3. Funaria Classification Class: Bryopsida ( Musci ) Order: Funariales Family: Funariaceae Genus: Funaria

4. Habit and distribution 117 species 15 spp in India Funaria hygrometrica – best known among mosses and found throughout the world Grow luxuriantly in humus rich soil and burnt soil Also occur on rocks and damp soil Some are epiphytic and grow on tree trunks

5. Gametophyte Morphology: Appear as velvety mats Gametophyte – also called as gametophore (bears sex organs) Differentiated into rhizoids, stem and leaves Green, erect and 1-3 cm in height Stem is branched – monopodial type Rhizoids – at base of gametophyte – branched, multicellular and thread-like, contain oil, but when exposed to light, develop chlorophyll and help in photosynthesis Leaves – small, ovate, bright green, spirally arranged on stem, midrib present, upper leaves bigger and lower ones smaller, sessile, broad base at point of attachment

6. Anatomy: Leaf – distinct midrib and wings Midrib – multilayered and thick Wings – single layered, cells contain chloroplast – carbon assimilation Stem – a) epidermis, b) cortex and c) central cylinder Epidermis – single layered, outermost layer, compactly arranged cells with chloroplasts – assimilatory function, cuticle and stomata absent Cortex – multilayered, parenchymatous cells, contain chloroplast in earlier stages but later disappear Central cylinder – thick walled, compactly arranged cells, acts as conducting tissue (water conduction)

7. Reproduction: Vegetative and sexual Vegetative reproduction: a) by primary protonema – spore germinate – develop into primary protonema – small buds – develop into new moss, protonema breaks up and propagate vegetatively b) by secondary protonema – protonema develop from other plant parts than spore. Detached part (leaf, stem, antheridium, rhizoids) – grow into new one c) by gemmae – small multicellular at leaf apices or sometimes on rhizoids d) by death and decay of prostrate system – decay of rhizoids – erect branch behaves as independent plant e) Apospory – develop wounds on sporophytic tissue from which protonema arise and develop into new plant – here it is by sporophytic tissue and not by spores

8. Sexual reproduction Antheridium 2 parts: stalk and main body Body surrounded by single layered jacket – contain chloroplast – turn red or brown on maturity Androcytes inside jacket layer At apical end of male branch, antheridia intermingle with several sterile paraphyses (hair-like structures) Paraphysis – multicellular, 4-5 cells arranges in uniseriate row, lower cells elongated, upper cells globular – indefinite function – assumed to hold water for developing antheridia Dehiscence – presence of moisture Rain water and dew collected in perichaetial leaves Develop apical pore – androcyte squeezes out

9. Archegonium Archegonial stalk longer than antheridial stalk Flask-shaped 3 parts: massive stalk, venter and neck Venter – 2 layered jacket – egg and venter canal cells Neck – 1 layered jacket – 6 or more neck canal cells On maturation, venter canal cells and neck canal cells disintegrate – form mucilage Cover cells separate to form passage

10. Sporophyte Foot, seta and capsule Foot – small, conical, embedded in gametophyte, poorly developed, absorb water and nutrients Seta – elongated, slender, and thread-like – bear capsule at apical end, cells elongated, mechanical function Capsule – pear-shaped 3 parts: apophysis, theca and upper region a) Apophysis – apical end of elongated seta, assimilatory function, stomata in epidermis

11. b) theca – central fertile region of capsule, many layers Outermost layer – epidermis Hypodermis below epidermis Chlorenchyma tissue next to hypodermis – contain chloroplast – photosynthesis Air spaces – transversed by trabeculae – 3-4 green cells – act as connection between chlorenchyma and outer spore sac of capsule Central region – pith like cylinder – columella – narrow at base, broad at apical end – connected to conducting strand of apophysis Columella surrounded by spore sac Spore sac – barrel-shaped, inner single layer, outer 3-4 layered In between outer an dinner spore sac are spore mother cells Spore mother cell – develop into spore tetrad of 4 spores

12. c) Upper region: Consists of operculum and peristome Operculum – 3-4 layers thick, outermost epidermal layer Rim is found in circular edge form – stretches inward from epidermis and connects peristome to epidermis of capsule Peristome – lies beneath operculum Consists of 2 incurved teeth called inner ( colourless ) and outer peristome (red) Annulus found just above rim – 5-6 epidermal cells Dehiscence – dry up on maturation Columella and outer thin walled tissues lose water and shrink up Spore sac tear off Annulus break and operculum thrown off Peristome teeth move outward hygroscopically – spores disperse

13. References Pandey B.P. (2009). Botany for degree students: B.Sc. First Year. S. Chand & Company Ltd. New Delhi.