Biology subjects

Crews, T. E.

Publications and source records attributed to Crews, T. E..

3 recordsLinked to original sources

bioRxiv2026

Alfalfa intercropping maintains intermediate wheatgrass grain yield relative to nitrogen fertilization across site conditions and stand ages

Intermediate wheatgrass (IWG; Thinopyrum intermedium) is a promising perennial grain crop, but yield instability remains a major challenge. We compared effects of nitrogen fertilization and intercropping with alfalfa (Medicago sativa L.) on IWG biomass, grain yield, and root traits across three stand ages at two nearby sites in eastern Missouri differing in soil properties (Planthaven Farms and Danforth Center Field Research Site). Four treatments (unfertilized IWG, fertilized IWG, IWG-alfalfa intercrop, and alfalfa monoculture) were established in a randomized complete block design with four replications per site. Biomass and grain yield were evaluated at per-row and field scales, while roots were measured to 1 m depth during the second stand age. Alfalfa intercropping maintained IWG grain yield without synthetic N fertilizer, although treatment responses varied by site and stand age. At Planthaven, differences became more pronounced as stands matured, with intercropped IWG producing the greatest per-row biomass and grain yield in stand age three. At the Danforth Center Field Research Site, intercropped IWG produced greater per-row biomass and grain yield than monocultures, whereas fertilized IWG tended to produce greater field-scale biomass; grain yield declined across treatments with stand age. Across sites, nitrogen fertilization increased vegetative biomass more consistently than grain yield. Despite having fewer IWG rows, intercrops maintained field-scale grain yield comparable to fertilized IWG in several site-years. Root traits responded weakly to management and were structured primarily by soil depth. These findings highlight the importance of site conditions, and stand age, when evaluating management strategies for perennial grain production.

plant biology↗

bioRxiv2019

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↗

bioRxiv2019

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↗