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Urban Forestry project continues!!!

Discussion on reading.

Reading

Natural shattering of seed in rice.

Genes of large effect vs. many genes of small effect

QTL analysis – what is it?

Crossing studies –

Regulation of abscission very important to plants

What do you think are the What do you think are the most important questions?most important questions?

How can the many How can the many challenges we face be challenges we face be

resolved?resolved?

Conservation BiologyConservation Biology

Plant diversity

Will start following the book much more closely.

Would be useful to bring your books to class.

Chapter 7 for today's lecture

Evolution of plant diversity

Endosymbiosis has evolved several times, including several separate events creating 'chloroplasts'

Figure 7.1

Figure 7.2

Algae

Red Algae (Rhodopytes)

Brown Algae (Phaeophytes)

Diatoms (Bacillariophytes)

Dinoflagellates

Chlorophytes– Chara

Red Algae

Red Algae

Typically in deep water

Often 'crustose'

Quite poorly known with very complicated life cycles

Brown Algae

Brown Algae

Kelp forests

'Plant-like' growth forms

Middle depth and often have organs that allow them to float.

Diatoms

Diatoms

Abundant and diverse in both marine and freshwater environments

Must go through sexual reproduction to restore size because of morphology.

Diatomaceous earth – an effective way to get rid of a flea infestation.

Dinoflagellates

Dinoflagellates

Unique morphology with two flagellae located in grooves.

Form important symbioses with reefs, sponges, and squids – zooxanthellae.

Diatomaceous earth – an effective way to get rid of a flea infestation.

Chara - “muskgrass”

A likely ancestor of all land plants

Algae as biofuels.

Many of the major players in the energy industry are moving away from this idea though.

Craig Venter has a team working on it.

Evolution of plant diversity

Figure 7.6

Invasion of land

“Bryophytes”?

Liverworts, Hornworts, and Mosses

Liverworts

Liverworts - Marchantia

Thallus – flattened body

Hornworts

Hornworts

Evolution of plant diversity

Figure 7.8

Tracheophytes

Lycophytes

Monilophytes – Psilotum, Ophioglossus, Equisetum

Algaophyton

Lycophytes – Lepidodendron

Lycophytes - Selaginella

Lycophytes - Lycopodium

Equisetum