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Native Forb Seed Production in Florida Genetics / Seed Dormancy Dave Czarnecki II, Zhanao Deng, Jeffrey G. Norcini*, Sarah Smith, Fred Gmitter, and M. Nageswara Rao
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Plant Material What matters? Sustainability Seed / plant origin (ecotype) Genetic diversity : sustainability
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AAAAAABABAAAAAAA AAAAAAAAAAAAAAAA ABACAAAAAACBAAAA AAAAAAAAAAAAAABA AAAABAAAAAAAAAAA AAAAAAAAAAAAAAAA AAAAACAABAAAAACA ABAAAAAAAAAAAAAA AAAABAAAAAABAAAA AAAAAAAAAAAAAAAA AAAAAAAABAAAAAAA AAAAAAAAAAAAAAAA AACAAABAAAAAAABA AAAAAAAAAAABAAAA AAAAAAAAABAAAAAA AAAAAAAAAAAAAAAC Gen. Diversity – Cultivar/Selection Genotypes of population – mostly A, some B and C
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B B B C CB B B C B C B B B B C B B B B C Gen. Diversity – Cultivar/Selection A is susceptible to a biotic or abiotic stress
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AAHAICB AB AILCMHI DCDMDBLCJBDBDADC ABACAIMDKIAIMBAD EIELDFCMLFDFEIEA MDADBADEILBMADFE DAMAFDFGMCFIDLMJ AKDEJCGGBCJCFCDG KBAIDA AEAADAMBAJ FJDCBGLMJGBGFJDM AFJDGCJKEIG AJFJK MKAGAHMLBHLHLKLL DDGCDIFGFCDEDDGG JACHJJB AKJDJEICH GLKAMKKDCKMKGLMD FMIKDLCBDLDLIMKB HADAJIDC ABJDHADC Genotypes of population – A to M Gen. Diversity – Natural/No selection
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HICBBILCMHI DCDMDBLCJBDBDDC BCIMDKIIMBD EIELDFCMLFDFEIE MDDBDEILBMDFE DMFDFGMCFIDLMJ KDEJCGGBCJCFCDG KBIDE DMBJ FJDCBGLMJGBGFJDM FJDGCJKEIGJFJK MKGHMLBHLHLKLL DDGCDIFGFCDEDDGG JCHJJBKJDJEICH GLKMKKDCKMKGLMD FMIKDLCBDLDLIMKB HDJIDCBJDHDC A is susceptible to a biotic or abiotic stress
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http://edis.ifas.ufl.edu/ep297
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Wildflower Seed Production Floridawildflowers.com
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Minimal weeds Maximizes yield Maintains genetic diversity Landscape Fabric System
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Seed Harvesting Vacuuming
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Genetics
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Coreopsis leavenworthii
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Prod. Pops.
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Leaf type Growth habit Plant survival through winter Days to bloom Flower color Flower size Phenotypic Diversity
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Molecular Diversity – advantages Insensitive to environmental changes Many data points generated 246 plants X 320 loci = 78,720 vs. 1,476 (Morphology) Screen large number of loci Relatively fast More accurate interpretation of population diversity DNA Markers and Diversity
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PCA Results Phenotypes Production and Natural C. Fla. Populations Genotypes
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Maintained identity even at locations distant from origin Also, noted that: High level of diversity within populations Low level of diversity among populations Possible to produce highly diverse seed in locations other than the area of origin Production Populations
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C. leavenworthiiC. tinctoria
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Can hybridize C. leavenworthii is narrowly endemic C. tinctoria is present in much of the US but only 6 Florida counties Escambia, Lake, Highlands, Miami-Dade, Madison and Leon counties C. tinctoria present in 3 of the same counties as C. leavenworthii Lake, Highlands, Miami-Dade C. leavenworthii and C. tinctoria
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C. tinctoria has trichomes on leaf petiole. Hybrids too? Morphological Markers C. tinctoria and hybrids have red spot. Hybrid
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One of the three field blocks for study of natural gene flow from C. tinctoria to C. leavenworthii. Seeds were being collected from one of the 27 pollen trap plots.
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Seed Dormancy
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Germination and emergence - weed interference - erosion Sustainability - seed bank reserves Seed Dormancy - Importance
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Seed origin (genetics) Harvest season (environment) - temp., light, water, nutrition Storage conditions Seed Dormancy
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After-ripening to break dormancy Afterripening is loss of the dormant state over some period of time through exposure of the seeds to a set of environ- mental conditions after maturation and separation from the parent plant. Foley, M.E. 2001. Weed Science 49:305-317 Coreopsis after-ripening study 1-24 weeks @ 59 or 90 o F - 33% RH, except 23% RH for C. lanceolata Then 24 weeks in commercial, cool storage unit - 23% RH and 63-66 o F Seed Dormancy
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cotyledon pericarp testa endosperm Coreopsis floridana
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Coreopsis basalis AR – 59 o F, 33% RH Results for seeds AR 12 wk, stored 24 wk @ 63-66 o F, 23% RH AR – 90 o F, 33% RH
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Coreopsis floridana AR – 59 o F, 33% RH Results for seeds AR 2 wk, stored 24 wk @ 63-66 o F, 23% RH AR – 90 o F, 33% RH *72% for seeds AR 24 wk, and then stored 24 wk * **75% for seeds AR 24 wk, and then stored for 24 wk **
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Coreopsis lanceolata AR – 59 o F, 23% RH Results for seeds AR 24 wk, stored 24 wk @ 63-66 o F, 23% RH AR – 90 o F, 23% RH
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Coreopsis leavenworthii AR – 59 o F, 33% RHAR – 90 o F, 33% RH Results for seeds AR 12 wk, stored 24 wk @ 63-66 o F, 23% RH
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Coreopsis after-ripening study C. basalis - AR at 59 and 90 o F; viability maintained C. lanceolata - best AR after 25-48 wk of cool temps. - maybe AR at 90 o F for 24+ wk - viability maintained C. floridana - slight AR but store cold/dry or lose viability C. leavenworthii - 90 o F increases germ but slight loss in viability Seed Dormancy
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Cool, dry environment temp. + RH 100 ex.: 35 o F, 40% RH 35+40 = 75 (best is RH < 50%, and total < 75) *** As temp. RH *** (must cool AND dehumidify air) Protect against insects and rodents Seed Storage
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Labs Specializing in Testing Seed of Native Species Ransom Seed Laboratory, Inc. PO Box 300 Carpinteria, CA 93014-0300 (805) 684-3427 Ransomsl@silcom.com http://www.ransomseedlab.com Mid-West Seed Services, Inc. 236 32nd Avenue Brookings, South Dakota 57006 (877) 692-7611 info@mwseed.com http://www.mwseed.com
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Leaf Type North: most complex Central: moderately complex South: most simple Growth Habit North, CP1, and C2: mostly all upright C3: mostly semi-upright or decumbent S1: almost entirely semi-upright or decumbent Plant Survival Little differentiation among populations Days to Bloom North: most days to bloom South: fewest days to bloom Flower Color and Size Possible gradient of size and color from north to south Phenotypic Diversity – Natural Populations
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Extremely uniform Very similar to a natural pop. from central Fla. Almost upright Correlation analysis Leaf, flower, and origin were highly correlated Phenotypic Diversity – Production Populations
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