Abstract Detail

Botanical foundations for perennial agriculture: Evolution and ecology of perennial herbaceous plants

Herron, Sterling [1], Ciotir, E. Claudia [1], Miller, Allison [1].

Evolution of annual and perennial herbaceous papilionoid legumes under natural and artificial selection.

Life history strategies involve suites of organismal reproductive, growth, and survival decisions which govern future evolutionary trajectories and can shed light on past adaptive drivers. In plants this is often characterized as the annual, monocarpic form and the perennial, polycarpic form. Relative differences in these forms have become agronomically relevant with the novel domestication of herbaceous perennial grains in efforts for ecological intensification of agroecosystems, attributed to perennials’ pervasive root systems, high resource capture, and stress-resilience. While the domestication syndrome of herbaceous annual and woody perennial species is well characterized, it is virtually unknown in herbaceous perennial grains. Major questions in this regard are whether herbaceous perennials can match or exceed conventional annual grains in reproductive output, multi-year yield stability, and if this strong selective pressure will expose unreconcilable growth allocation trade-offs between reproductive and perennating, vegetative organs. In the legume family (Fabaceae), there is a broad diversity of both annual and perennial herbaceous species, primarily within subfamily Papilionoideae. Repeated evolution of these forms presents the opportunity to test whether similar evolutionary changes have occurred with analogous selective pressures across diverse lineages. This study seeks to compare relative changes in germination patterns, growth rate, biomass allocation / tradeoff, and reproductive effort for 1) congeneric wild annual and perennial species and 2) congeneric domesticated annual and perennial species relative to their wild progenitors. We hypothesized that relative differences between annual and perennial congeners will be largely divided along the theoretical plant economics spectrum (PES), with annuals showing characteristically acquisitive growth (high relative growth rate and reproductive effort) and perennials conservative growth (low relative growth rate and reproductive effort), with both annuals and perennials becoming more acquisitive with domestication. We grew out multiple populations of three to twelve annual and perennial species from each of the economically important genera Astragalus, Glycine, Lathyrus, Lupinus, Phaseolus, and Vicia under constant conditions. Trends are idiosyncratic for each genus, with germination percentage being similar but typically higher for annuals, and seed size typically higher for annuals, except in the case of tropical Phaseolus. Germination and seed size generally decrease and increase, respectively, with domestication in both annuals and perennials, although differences may be impacted by germplasm age, geographic origin, and targets of selection. Future work will follow reproductive effort of perennial plants in a field setting over three years, as well as the population genetics of annual and perennial congeneric Strophostyles species.

1 - Donald Danforth Plant Science Center, Miller Lab Group, 975 N Warson Road , St Louis, MO, 63132, USA

plant life history
life history
life history strategy
herbaceous perennial
perennial agriculture
perennial crop
perennial evolution
annual and perennial
perennial herbaceous
perennial grains
sustainable agriculture
ecological intensification
plant economics spectrum
domestication syndrome
artificial selection
legume crop
crop wild relative

Presentation Type: Colloquium Presentations
Number: 0010
Abstract ID:344
Candidate for Awards:None

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