| Multiplication - predominantly vegetative. Intensive growth
occurs from June through August. Plants double the mass of their
body in 1 - 6 days, and the doubling of frond number occurs in 2 - 3 days.
Mode of pollination - cross-fertilization, with the aid of the wind or
insects.
Flowering of duckweeds
At the initiation of flowering, fronds are always located on the surface
of the water, with air chambers more developed than in the vegetative state.
Vegetative fronds of Lemna gibba. |
Flowering fronds of Lemna gibba. |
The period of flowering, from the moment of the initiation of flowering
fronds to the end of floral development, is about 20 days.
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| As duckweed prepares for flowering,
the volume of the fronds increases. |
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Flowering fronds of Lemna, Krasnodar, 1995 |
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| Common form of inflorescence of Lemna
minor |
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Common form of inflorescence of Lemna
trisulca. |
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| Stigma of the first flower of Lemna gibba. |
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| The stigma and the stamen of the 2nd male
flower of Lemna. |
Bottom view of flowering fronds of Lemna gibba. |
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Newly emerging fronds in flowering duckweed
are as ready for flowering as the maternal
frond. Evidence for this is the swollen air cavities in the young
frond. |
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Flowering fronds of Lemna minor.
In contrast to L. gibba, flowering
L. minor does not increase the dimensions of its fronds. |
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Modes of Multiplication 
