Selecting crops that express certain reproductive, leaf, and root traits has formed detectable, albeit diverse, crop domestication syndromes. However, scientific and informal on-farm research has primarily focused on understanding and managing linkages between only certain domestication traits and yield. There is strong evidence suggesting that functional traits can be used to hypothesize and detect trade-offs, constraints, and synergies among crop yield and other aspects of crop biology and agroecosystem function. Comparisons in the functional traits of crops vs. wild plants has emerged as a critical avenue that has helped inform a better understanding of how plant domestication has reshaped relationships among yield and traits. For instance, recent research has shown domestication has led important economic crops to express extreme functional trait values among plants globally, with potentially major implications for yield stability, nutrient acquisition strategies, and the success of ecological nutrient management. Here, we present an evidence synthesis of domestication effects on crop root functional traits, and their hypothesized impact on nutrient acquisition strategies in organic and low input agroecosystems. Drawing on global trait databases and published datasets, we show detectable shifts in root trait strategies with domestication. Relationships between domestication syndromes in root traits and nutrient acquisition strategies in low input systems underscores the need for a shift in breeding paradigms for organic agriculture. This is increasingly important given efforts to achieve Sustainable Development Goal (SDG) targets of Zero Hunger via resilient agriculture practices such as ecological nutrient management and maintenance of genetic diversity.

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Involving farmers directly in early‐generation selection may contribute to the development of well‐adapted organic wheat (Triticum aestivum L.) germplasm. This project involved a partnership between a professional breeder and farmers. Progeny from 19 spring wheat crosses were distributed to eight organic farmers (three populations per farmer) in southern Manitoba, Canada. Each farmer selected for three consecutive years, resulting in 23 unique advanced lines. The farmer‐selected lines were compared with eight registered cultivars and one landrace cultivar in replicated field experiments at a total of three site years in 2014 and 2015. Although there was significant variation in agronomic performance of different farmer‐selected lines, the farmer selections were generally taller, later maturing, more susceptible to lodging; farmer selections were higher yielding than the check cultivars at one site‐year. When selecting from the same population, farmers produced distinctively different lines; differences were observed in disease response, days to maturity, height, lodging, and yield. The highest yielding wheats included farmer‐selected lines, a heritage cultivar, and two modern checks, one bred for organic conditions and one with a unique insect resistance trait. This preliminary study shows the potential of farmers working together with a professional breeder to produce wheat germplasm for organic production. Results also confirm the value of certain conventional cultivars to organic production.

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Interest in intercropping semi-leafless field peas (Pisum sativum L.) is increasing as a means of weed control in organic production. We evaluated field pea (cv. CDC Amarillo) grown alone or intercropped with three seeding rates of either barley (Hordeum vulgare L.), mustard (Brassica juncea L.), or oats (Avena sativa L.). A full seeding rate of field pea was used in each instance, resulting in an additive intercropping design. Each crop combination was conducted in a separate experiment, three times over two years (2019 and 2020) in Carman, Manitoba. Measurements included crop and weed biomass production, grain yield and quality, and net return. Intercrops reduced weed biomass at maturity from 17 to 44% with barley and oats being more suppressive than mustard. Intercrops also reduced field pea yield from 6 to 26%, but increased field pea seed mass. Barley at the high seeding rate provided the most weed suppression per unit of field pea yield loss (2.62 kg of weed suppression per kg of field pea yield loss) compared with oat (1.29) and mustard (0.87). Barley and mustard intercrops decreased net return compared to monoculture field pea. Under low weed pressure (1150 kg ha-1 weed biomass at maturity) and earlier seeding, oat intercrops reduced net return. However, under weedy conditions (2649 kg ha-1) and later seeding, field pea-oat intercrops significantly increased net return. In conclusion, while all three intercrop mixtures reduced weed biomass, reductions in field pea yields were observed, and net return benefits were observed only in certain circumstances.