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The upcoming discussion will update you about the difference between Welwitschia and Gnetum.
Difference # Welwitschia:
1. In welwitschia, plants are highly restricted in their distribution and found only in a narrow coastal belt in south-west Africa.
2. Plants occur only in extremely xerophytic conditions in welwitschia.
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3. Plant resembles a gigantic turnip in welwitschia and trees and shrubs are absent.
4. In welwitschia, tap root is very long which enables the plants to absorb subsurface water.
5. Distinct nodes and internodes on the stem are absent in it.
6. The stem is un-branched in it.
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7. Only two opposite leaves, which persist throughout the life, are present in welwitschia.
8. Scaly leaves are absent in it.
9. In welwitschia, both the leaves are thick, leathery, ribbon like, persistent, and reach up to 2 metres or more in length.
10. Leaves bear parallel venation in welwitschia .
11. Leaves split at maturity in welwitschia .
12. In welwitschia, a deep groove is present in the shoot apex.
13. The strobili are borne terminally on the dichasially branched inflorescence axis in it.
14. The male flowers are bisexual in welwitschia, each bearing an abortive ovule in the centre along with six stamens.
15. Male prothallial cells are absent in the male gametophyte of welwitschia.
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16. Over one thousand free nuclei are distributed evenly in the cytoplasm of female gametophyte of wetwitschia.
17. in welwitschia, prior to fertilization the female gametophyte becomes completely cellular.
18. A tent-pole is absent in it.
19. Prothallial tubes develop in the female gametophyte during fertilization of welwitschia.
Difference # Gnetum:
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1. In gnetum, plants and widely distributed in the tropical and subtropical forests of Malaysia, China, India, West Africa, etc.
2. Plants occur in moist and humid regions of tropical forests in gnetum.
3. Most of the gnetum species are lianes, a few are trees and some are shrubs.
4. Tap root is comparatively less developed in it.
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5. Nodes and internodes are well-marked on the stem of gnetum.
6. The stem is extensively branched in gnetum.
7. In gnetum, numerous leaves are present.
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8. Scaly leaves are also present along with foliage leaves in it.
9. Foliage leaves are small, thin, possess a broad lamina, and are angiosperm like in gnetum.
10. In gnetum, leaves bear unicostate reticulate venation.
11. Foliage leaves never split in gnetum.
12. The shoot apex has no groove in it.
13. The strobili are only very rarely terminal in gnetum. They arise generally singly in the leaf axil.
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14. The male flowers are unisexual in it.
15. In gnetum, the male gametophyte bears a single male prothallial cell.
16. Free nuclei in the female gametophyte of gnetum are peripherally arranged.
17. The female gametophyte is only partly cellular before fertilization in gnetum.
18. A tent-pole is present in the female gametophyte in some species of gnetum.
19. Prothallial tubes are not formed in it.
