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Herron, S. A.

Publications and source records attributed to Herron, S. A..

5 recordsLinked to original sources

Comparative population genomics in two sympatric species of Strophostyles (Fabaceae) with contrasting life histories

PREMISE OF THE STUDYLife history is an important predictor of population genetic variation, although this link remains unexplored in numerous important plant lineages. One such lineage is the legume genus Strophostyles, which contains both annual and herbaceous perennial vines native to eastern North America. Specifically, it remains to be determined whether Strophostyles species with different life histories show different patterns of genetic differentiation and diversity, as well as if these species hybridize across their range. METHODSHere we sampled the perennial Strophostyles helvola and annual S. leiosperma in five sites across a latitudinal transect in the central United States, including three sites where the species occur in sympatry. Using genotyping-by-sequencing, we identified 5556 polymorphic SNPs across 166 individuals. KEY RESULTSThere is no evidence that Strophostyles helvola and S. leiosperma hybridize in the populations examined. Within species, Strophostyles helvola (perennial) displays admixture among populations, while S. leiosperma (annual) does not, although both species show more genetic diversity among rather than within populations. Patterns of genetic diversity are varied across populations of both species, with both heterozygote excess and deficiency. CONCLUSIONSThe complex patterns of genetic differentiation and diversity warrant further investigation of life history and population dynamics in Strophostyles, particularly mating system and modes of gene flow. This study exemplifies the diversity of population genetic patterns even within a small genus, and it reinforces the need to characterize such diversity in non-model systems to gain a more complete understanding of how life history contributes to population genetics.

plant biology↗

The role of genus and life span in predicting seed and vegetative trait variation and correlation in Lathyrus, Phaseolus, and Vicia (Fabaceae)

PREMISE OF THE STUDYAnnual and perennial life history transitions are abundant among angiosperms, and understanding the phenotypic variation underlying life span shifts is a key endeavor of plant evolutionary biology. Comparative analyses of trait variation and correlation networks among annual and perennial plants is increasingly important as new perennial crops are being developed in a predominately annual-based agricultural setting. However, it remains unclear how seed to vegetative growth trait relationships may correlate with life span. METHODSWe measured 29 annual and perennial congeneric species of three herbaceous legume genera (Lathyrus, Phaseolus, and Vicia) for seed size and shape, germination proportion, and early vegetative height and leaf growth over three months in order to assess relative roles of genus and life span in predicting phenotypic variation and correlation. KEY RESULTSGenus was the greatest predictor of seed size and shape variation, while life span consistently predicted static vegetative growth traits. Correlation networks revealed that annual species had significant associations between seed traits and vegetative traits, while perennials had no significant seed-vegetative associations. Each genus also differed in the extent of integration between seed and vegetative traits, as well as within-vegetative trait correlation patterns. CONCLUSIONSGenus and life span were important for predicting aspects of early life stage phenotypic variation and trait relationships. Differences in phenotypic correlation may indicate selection on seed size traits will impact vegetative growth differently depending on life span, which has important implications for nascent perennial breeding programs.

plant biology↗

Comparative analysis of seed size, germination, and vegetative allocation in annual and herbaceous perennial crops and their wild relatives in Lupinus and Phaseolus (Fabaceae)

Herbaceous perennial species are receiving increased attention for their potential to provide both edible products and ecosystem services in agricultural systems. Many legumes (Fabaceae Lindl.) are of special interest due to nitrogen fixation carried out by bacteria in their roots and their production of protein-rich, edible seeds. However, herbaceous perennial legumes have yet to enter widespread use as pulse crops, and the response of wild, herbaceous, perennial species to artificial selection for increased seed yield remains under investigation. Here we compare cultivated and wild accessions of congeneric annual and herbaceous perennial legume species to investigate associations of lifespan and cultivation with seed size, germination, and first year vegetative growth patterns, and to characterize covariation among traits. We use \"cultivated\" to describe accessions with a history of human planting and use, which encompasses a continuum of domestication. Analyses focused on three annual and eight perennial Lupinus species, and three annual and four perennial Phaseolus species. We found a significant association of both lifespan and cultivation status with seed size (weight, area, length), germination proportion, node number, stem diameter, shoot dry mass, and root dry mass. Wild seed size was greater in annuals for Lupinus and greater for perennials in Phaseolus. Germination was lower in wild perennials than wild annuals in both genera, and vegetative allocation was roughly equivalent across lifespans in wild Phaseolus. Relative to wild forms, both cultivated annual and cultivated perennial accessions exhibited greater seed size, lower germination proportion, and larger overall plant size. Seed size traits were positively correlated with vegetative growth traits, and all biomass traits examined here were positively correlated. This study highlights some basic similarities and differences between annual and herbaceous perennial legumes, and provides insights into how perennial legumes might respond to artificial selection compared to annual species.

plant biology↗

Comparative analysis of perennial and annual Phaseolus seed nutrient concentrations

Malnutrition is a global public health concern and identifying mechanisms to elevate the nutrient output of crops may minimize nutrient deficiencies. Perennial grains within an agroforestry context offers one solution. The development and integration of perennial crops for food has critically influenced dialogue on the ecological intensification of agriculture and agroforestry. However, the nutrient compositions of wild, perennial, herbaceous species, such as those related to the common bean (Phaseolus vulgaris) are not well known. In this study, seed amino acid and ion concentrations of perennial and annual Phaseolus species were quantified using ionomics and mass spectrometry. No statistical difference was observed for Zn, toxic ions (e.g. As) or essential amino acid concentrations (except threonine) between perennial and annual Phaseolus species. However, differences were observed for some nutritionally important ions among and within lifespan groups. Ca, Cu, Fe, Mg, Mn, and P concentrations were higher in annual species. Intraspecific variability in ion concentrations and amino acids was observed within species; further, ion concentrations and amino acids differ among annual species and among perennial species. Ion and amino acid concentration appear to be largely independent of each other. These results suggest variability in ion and amino acid concentrations exist in nature. As new crop candidates are considered for ecological services, nutritional quality should be optimized to maximize nutrient output of sustainable food crops.

plant biology↗

Building a botanical foundation for perennial agriculture: Global inventory of wild, perennial herbaceous Fabaceae species

O_LIConcerns about soil health and stability are focusing attention on crops that deliver both agricultural products and ecological services. Deep rooted, perennial plants that build soil organic matter, support diverse below-ground microbial communities, and produce edible seeds are key components underpinning ecological intensification; however few perennial, herbaceous crops have been domesticated for food.\nC_LIO_LITo facilitate development of edible, perennial, herbaceous crops, including perennial grains, we constructed an online resource of wild, perennial, herbaceous species - the Perennial Agriculture Project Global Inventory (PAPGI; http://www.tropicos.org/Project/PAPGI). The first component of this project focuses on wild, perennial, herbaceous Fabaceae species. We extracted taxonomic names and descriptors from the International Legume Database and Information Service. Names were added to PAPGI, a special project within the botanical database TROPICOS, where they link to specimen records and ethnobotanical and toxicological data. PAPGI includes 6,644 perennial, herbaceous Fabaceae species. We built a searchable database of more than 60 agriculturally important traits. Here we highlight food and forage uses for 314 legume species, and toxicological data for 278 species.\nC_LIO_LIThe novel contribution of PAPGI is its focus on wild, perennial herbaceous species that generally have not entered the domestication process but that hold promise for development as perennial food crops. By extracting botanical information relevant for agriculture we provide a dynamic resource for breeders and plant scientists working to advance ecological intensification of agriculture, and for conservation managers working to preserve wild species of potential agricultural importance.\nC_LI\n\nSocietal Impact StatementAgroecosystems are constantly evolving to meet the needs of a growing population in a sustainable manner. Perennial, herbaceous crops deliver both agricultural products and ecological services. Until recently, edible, perennial, herbaceous crops, including perennial grains, were absent from agriculture. Perennial, herbaceous crops can be developed through wide hybridization between annual crops and perennial relatives or by de novo domestication of wild species. The diversity of wild, perennial, herbaceous legume species documented by the PAPGI increases resources available to breeders of perennial, herbaceous legumes, and raises awareness about previously untapped wild plant diversity in future crop development.

evolutionary biology↗