Capsicum Phylogeny and Domestication Brian Walsh Family Subfamily Tribe Solanaceae Solanoideae Capsicinae since 1999 Estimated 25 species my count 37 Native to South and Central America Current distribution is global One of the most utilized spice in the world Part of human diet for 9000 years All diploid Typically self fertilize Most n 12 some n 13 One of the most diversely utilized plants Spice Food Dye Medicine Weapons Poison Drinks Deterrent Insecticide Pesticide Preservative Snuff Rituals Tribute Town Names Punishment Domestication Davenport 1970 proposes all five domesticated species arose from a single ancestor C frutescens L Lumper based on morphology Heiser 1971 proposes each domesticated species arose from its own unique wild ancestor Splitter hybridization studies Pickersgill 1972 agrees with Heiser different cultivated species show a combination of characters suggesting domestication by different groups of people living in different areas Eshbaugh 1983 argues at least three distinct domesticated lineages based on morphology plant breeding and enzyme analysis C chacoense is plesiomorphic Agricultural Centers of the New World and the theoretical flow of speciation View from 1000000 km above 5 18 S 63 55 W Based on C chacoense Domesticated Characters in Capsicum Domesticated Gigantism of fruit Altered fruit shape Fruit color other than red Retained on peduncle a maturity Variable capsaicin levels Wild small fruit Fruit round Red fruit Peduncle dehiscence at maturity High capsaicin levels Capsicum annuum Eshbaugh s breakdown into flower color categories why Capsicum annuum complex C annuum var annuum C annuum var avicular C frutescens white flowers C chinense C chacoense Capsicum baccatum group C baccatum var praetermissum C baccatum var pendulum C baccatum var baccatum white flowers with yellow spots Capsicum eximium complex C pubescens C eximium C cardenasii Total species 8 purple flowers C frutescens Tabasco C baccatum var praetermissum Capsicum eximium Capsicum eximium C baccatum var praetermissum Capsicum cardenasii Only species that strictly outcrosses Flower color classification of Capsicum Color categories inaccurate too many exceptions Only a fraction of total species included Doesn t agree with molecular data Current phylogenetic questions Monophyly of genus Resolving species relationships Capsicum Monophyletic Modified from Bohs Olmstead 1997 A B C A B C A A C Monophyletic A A C Not Monophyletic Walsh 2001 chloroplast atpB rbcL spacer data Walsh 2001 chloroplast atpB rbcL spacer data Walsh 2001 combined atpB rbcL spacer and waxy data n 12 13 Walsh 2001 chloroplast atpB rbcL spacer data Capsicum monophyly Intact for the time being Odd C ciliatum seems to be the weak link n 13 Mascone s missing tree Mascone 2003 Flow cytometry and Feulgen densitometry 1C value of DNA an equation for calculating genome size in absolute units Genome size in Mbp Visualization of Mascone s results Capsicum anuum complex C annuum var annuum C annuum var avicular C frutescens white flowers C chinense C chacoense United by similar DNA amount and little heterochromatin 1C G C chacoense 3 35 3273 C annuum var annuum 3 38 3312 C frutescens 3 40 3332 C chinense 3 42 3352 Capsicum baccatum group C baccatum var praetermissum C baccatum var pendulum C baccatum var baccatum C baccatum var umbilicatum white flowers with yellow spots New variety described in 1998 Domesticated status unknown Similar DNA amounts not surprising 1C G C chacoense 3 35 3273 C annuum var annuum 3 38 3312 C frutescens 3 40 3332 C chinense 3 42 3352 C baccatum var pendulum 3 69 3621 C baccatum var baccatum 3 71 3636 C baccatum var umbilicatum 3 76 3636 Interpreted from data not explicitly stated Capsicum eximium complex C pubescens C eximium purple flowers C cardenasii C parvifolium synonym with C cardenasii but description is off tree C parvifolium only compared to C campylopodium points out distantly related and nothing more C campylopodium groups with C pubescens large genome size and large amounts of heterochromatin forming complex patterns tone implies trepidation C eximium has DNA content intermediate between C baccatum and C pubescens but genome size supports close relationship to C pubescens as well as isozyme and cross studies 1C G C chacoense 3 35 3273 C annuum var annuum 3 38 3312 C frutescens 3 40 3332 C chinense 3 42 3352 C baccatum var pendulum 3 69 3621 C baccatum var baccatum 3 71 3636 C baccatum var umbilicatum 3 76 3636 C eximium 4 06 3979 C pubescens 4 47 4381 C campylopodium 5 14 5032 C parvifolium cardenasii 5 77 5655 However Mascone claims his data supports his hypothesis Increase in DNA amount is evolutionary advancement C chacoense most plesiomorphic ancestral C campylopodium most advanced n 13 in more recently evolved Mascone tree rooted Least DNA C chacoense C annuum var annuum C frutescens C chinense C baccatum var pendulum C baccatum var baccatum C baccatum var umbilicatum C eximium C pubescens Most DNA C campylopodium x 13 C parvifolium cardenasii Mascone Least DNA molecular C chacoense C annuum var annuum C frutescens C chinense C baccatum var pendulum C baccatum var baccatum C baccatum var umbilicatum C eximium C pubescens Most DNA C campylopodium x 13 C parvifolium cardenasii ancestral X 13 species C ciliatum C buforum C campylopodium C cornutum C schottianum C villosum C pereirae C friburguense 3 unnamed Capsicum Capsicum flexuosum n 13 n 12 Conclusion Capsicum needs more research Appears to be an x 12 x 13 split in distant past research hindered by incomplete sampling Difficult to study domestication when phylogeny unresolved 6 new species identified in last 8 years Naga Morich Following Photos unused in presentation Cherrape o Cherry Pepper Bolivian rainbow Chilaca Fluorescent Fredrik from Amalfi Jalape o Biker Billy Lemon black pepper Little nubian O odham Indian Piquin Peter Pepper Pimenta Doce Poblano Suryamukhi Tepin Variegata C Frutescens Naga Jolokia Tezpur PI451762 Tabasco C02466 Antillerna Paris C chinense Capsicum galapagoense C chacoense PI560944 Putapario C Pubescens Capsicum eximium praetermissum C ciliatum Capsicum Cardenasii C tovarii
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