Angiosperms. Seeded. Gymnosperms. Tracheophytes (vascular plants) Ferns Club mosses. Seedless. Fresh water alga. Mosses Hornworts

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1 Evolution

2 Seeded Angiosperms Fresh water alga Tracheophytes (vascular plants) Bryophytes (nonvascular plants) Seedless Mosses Hornworts Gymnosperms Ferns Club mosses Liverworts

3 Why did humans become farmers and not remain hunter/foragers?

4 When Did Crops Evolve Time period > 5,000 years 1,000 to 5,000 years < 1,000 years Evidence of crop cultivation pea, barley, wheat, maize, millet, lentil, beans,, rice, potato. Sugar beet, sunflower, soybean, alfalfa, onion, cotton. rapeseed, coffee, rubber, macademia nut.

5 sunflower... potato, maize, bean. cotton, rubber. sugarbeet, rapeseed.. millet, coffee barley, wheat,. lentil, pea.. alfalfa, apple. rice, soybean Macademia

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7 Potato Solanum tuberosum ssp tuberosum 2n = 4x = 48

8 South American Indian called the crop papa. The name potato comes from the Caribbean Aeawak Indian word batata Named Solanum tuberosum by Casper Banhin in 1596

9 Why are the world record potato yields in Idaho and Holland? How did the potato crop evolve so quickly?

10 How did the potato evolve from this to this is a very short period of time?

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12 1992

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14 Genetic Variability How did crop evolution happen Selection Pressure

15 Charles Darwin Born in England, educated in Scotland. The father of evolution Most famous for his travels on the Beagle to the Galapagos Islands. Survival of the fittest. Wrote The Origin of Species.

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17 Crop Domestication Wild Domesticated

18 Natural selection favors plant types which would have greatest chance of survival, reproduction, and distribution of progeny Human selection is the result of conscious decisions by the farmer or plant breeder to keep progeny from a certain parent over others

19 Greater progeny dispersal: cereals, potato, strawberry. Altered seed/tuber dormancy: oats, rice, beans, onion, carrot. Increased spininess: pineapple, lettuce, egg plant. Increased toxicity in seeds and fruits: bean, potato, tomato.

20 Less branched, fewer inflorescence more determinant growth: most cereals, sunflower, hemp. Reduced spininess: sisal, pineapple, lettuce, yams. Develop of attractive colors: most fruit, maize, pulses, peppers, potato. Development of quality for multiple uses: most crops.

21 Increased yield: all crops. Increased resistance to pests and diseases: all crops. Reduced plant size (dwarfism): wheat, barley, peach, etc. Shorter lifecycle (towards annual crop): rye, cotton, etc.

22 Ploidy describes the number of chromosome sets in each cell. Most agricultural crops are diploids. Agriculturally important crops include alloploids and autoploids.

23 Diploid X 2n = 2x = 6 2n = 2x = 6 2n = 2x = 6

24 Barley Carrot Apple Corn

25 2n = 4x = 14 Allopolyploidy X 2n = 2x = 6 2n = 2x = 8

26 Wheat Sugarcane Cotton Canola

27 Autopolyploidy X 2n = 2x = 6 2n = 2x = 6 4n = 4x = 12

28 Potato Peanut Strawberry Coffee

29 Domestication has been taking place continually for over 9000 years, at roughly constant rate

30 Where did domestication occur? Domestication and crop evolution has occurred, and is still occurring, wherever agriculture was practiced

31 All sorts of people, from early farmers, to modern-day farmers and plant breeders

32 How did these crops evolve? Selection in crops has been a combination of natural and human selection a process similar to Darwinism

33 Put things into prospective. Centers of crop origins is often associated weedy relatives. Weedy relatives have desirable traits that we introgress into our new crops. Knowing how and where are crops were developed helps to know how best to proceed in the future.

34 Food