Breadfruit A Tale of Two Domesticates?

Outline Artocarpus altilus Artocarpus altilus Biology and Distribution Biology and Distribution The Relatives The Relatives Methods of Determination Methods of Determination Origins… Origins…

Artocarpus altilus Moraceae Tree Crop Variety of uses Grown for infructescence rather than vegetative storage structures Staple of Oceania 2 “generalized” cultivars Seedless Few-->Many Seeded High productivity Seasonal Mmm…just like potatoes A. altilus (Ken Sytsma)

Breadfruit Biology Monoecious Pollen quantity varies Parthenocarpic fruit development in seedless Pollination mechanism unknown

Distribution

Fruiting Season Fruit Shape Fruit Color & Texture Infructescence surfaces Flavor Sections Leaves Seeds SEMs of trichomes Infertility 2n=3x=˜84; 2n=2x=56

Ranges of Close Relatives A. mariannensis A. camansi Fig 2. Zerega et al. (2005)

Methods of Determination Morphology, ITS and trnL-F region Morphology, ITS and trnL-F region AFLPs AFLPs Isozymes Isozymes Fig 10.2

AFLP Data Fig. 10.4

Fig. 3 Zerega et al. (2005) NJ TreeFig. 4

AFLP (cont.) Fig Fig. 3 Zerega et al. (2004)

MDH isozyme phenotypes & AFLP markers Fig. 10.3

What trends are seen in the data? Melansian and Polynesian breadfruit cultivars are more closely related to A. camari Melansian and Polynesian breadfruit cultivars are more closely related to A. camari Micronesian cultivars are closely related to Polynesian and Melanesian A. camansi- derived breadfruit and to A. mariannensis Micronesian cultivars are closely related to Polynesian and Melanesian A. camansi- derived breadfruit and to A. mariannensis Micronesia has the greatest genetic diversity; however, Polynesia cultivars are most genetically differentiated Micronesia has the greatest genetic diversity; however, Polynesia cultivars are most genetically differentiated Dependent on mode of reproduction and human selection Dependent on mode of reproduction and human selection

Analysis of Molecular Variance Based on AFLP Individual Islands Serve as Repositories for Genetic Diversity

Pattern and Process and Man’s Migrations

Melanesia and Polynesia Assumption: Assumption: High genetic variability=Region of Origin High genetic variability=Region of Origin Colonization during Pleistocene (40,000 yrs ago), dispersal of A. camansi to “near” Oceania, and human selection Colonization during Pleistocene (40,000 yrs ago), dispersal of A. camansi to “near” Oceania, and human selection Lapita cultural complex shifted to vegetative propagation for longer voyages (4,000 yrs ago) Lapita cultural complex shifted to vegetative propagation for longer voyages (4,000 yrs ago)

From Fig 1. Zerega et al (2004)

Micronesia Triploid A. camansi-derived “E Polyn” Triploid A. camansi-derived “E Polyn” Hybrid cultivars Hybrid cultivars Fertile and sterile diploids and sterile triploids Fertile and sterile diploids and sterile triploids Human involvement a must as ranges of A. camansi and A. mariannensis do not overlap Human involvement a must as ranges of A. camansi and A. mariannensis do not overlap Settled from multiple directions many times… Settled from multiple directions many times…

From Fig 1. Zerega et al (2004)

What about the rest of the World?

Travels of the HMS Bounty X

Captain Bligh Transport Breadfruit to the Caribbean from Tahiti on the HMS Bounty Transport Breadfruit to the Caribbean from Tahiti on the HMS Bounty The “No Paradise” rule The “No Paradise” rule Mutiny Mutiny Navigated 3600 nautical miles using a sextant and a pocket watch Navigated 3600 nautical miles using a sextant and a pocket watch Pitcairn Island Pitcairn Island Returned and took 347 breadfruit plants to St. Vincent and Jamaica on February 5th, 1793 Returned and took 347 breadfruit plants to St. Vincent and Jamaica on February 5th, 1793

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