Weather and landscape influences on pollinator visitation of flowering winter oilseeds (field pennycress and winter camelina)

Abstract

Flowers of field pennycress (Thlaspi arvsense L.) and winter camelina (Camelina sativa (L.) Crantz.) produce abundant pollen and nectar in early spring and thereby may be valuable for pollinators. Insects observed in field plots of these flowers were classified into seven easily identifiable groups (bumblebee, honeybee, solitary bee, butterfly/moth, beetle, fly and other) and monitored for 2 years at three sites in the Upper Midwest region of the USA. Average seasonal observations across years and sites varied from 1.6 to 5.3 total insects/min for field pennycress and 1.4 to 4.5 insects/min for winter camelina. Lowest visitation rates occurred in central Iowa and highest rates in south‐eastern Minnesota for both crops. Multiple regressions showed that visitation rates for specific insect groups were correlated poorly but significantly (p < .10) with select variables. For example, in field pennycress, visitation by combined bumblebees and honeybees (Apidae) increased with greater air temperature at sampling time and annual site precipitation, whereas fly (Diptera) visitation was related to sampling date and flower cover. Similarly, in winter camelina, solitary bees were linked to increasing air temperature at sampling time and annual site precipitation, whereas flies were correlated with wind speed and flower cover at sampling. Field pennycress and winter camelina are reliably attractive to beneficial pollinating insects across a wide geographic region, but visitation rates and proportional representation of various insect groups depended on a range of site and weather characteristics.

Differential effects of soil conservation practices on arthropods and crop yields

“…We incorporated temperature and precipitation variables into analyses because our sites spanned a mild precipitation and temperature gradient (PRISM Climate Group, 2020), and because weather can influence insect biodiversity (e.g., Forcella et al, 2021; Skellern et al, 2017). To measure weather variables, we gathered daily temperature and precipitation estimates from PRISM (PRISM Climate Group, 2020).…”

“…These variables were not collinear (Table S4). It was necessary to control for year, weather, and field size because all are known to affect insect abundance and biodiversity (e.g., Aldercotte et al, In press; Forcella et al, 2021; Fragoso et al, 2021; Skellern et al, 2017; Smith et al, 2020). Because abundance data were overdispersed, we used negative binomial regressions (MASS package, Venables & Ripley, 2002).…”

Plant Breeding for Intercropping in Temperate Field Crop Systems: A Review

“…In intercropping systems, the winter annuals are interplanted with summer annual row crops such as corn or soybean prior to seed formation ( Figure 6 ). This strategy reduces the fallow period between crops, provides ecological benefits such as pollen for early-season pollinators and reduced leaching of nitrogen into groundwater sources ( Weyers et al, 2019 ; Forcella et al, 2021 ), and produces harvestable yield from both cropping system components.…”

“…Intercropping represents within-field diversity, is defined as growing two or more crop species simultaneously in the same field, and encompasses a range of practices including mixed intercropping (growing component crops simultaneously with no distinct row arrangement), row intercropping (growing component crops simultaneously in different rows), strip intercropping (growing component crops simultaneously in different strips), and relay intercropping (growing component crops with overlapping growth periods; Andrews and Kassam, 1976 ). Intercropping can provide valuable benefits, including increased yield ( Trenbath, 1974 ; Hauggaard-Nielsen et al, 2001 ; Nyfeler et al, 2009 ; Finn et al, 2013 ; Martin-Guay et al, 2018 ; Li et al, 2020 ), yield stability ( Rao and Willey, 1980 ; Raseduzzaman and Jensen, 2017 ), improved crop quality ( Sleugh et al, 2000 ; Bélanger et al, 2014 ), reduced pest and disease impacts ( Altieri, 1999 ; Boudreau, 2013 ; Gaba et al, 2015 ), improved weed management ( Hauggaard-Nielsen et al, 2001 ; Finn et al, 2013 ; Johnson et al, 2017 ; Connolly et al, 2018 ; Hoerning et al, 2020 ), reduced input needs ( Nyfeler et al, 2009 ; Gaba et al, 2015 ; Raskin et al, 2017 ), improved soil health ( Cong et al, 2015 ; Li et al, 2021 ), support for a wide range of native pollinators ( Eberle et al, 2015 ; Forcella et al, 2021 ), and a range of other ecosystem services, such as wildlife conservation, soil conservation, water quality improvements ( Weyers et al, 2021 ), and carbon sequestration ( Malézieux et al, 2009 ). Intraspecific diversity in the form of cultivar mixtures can provide benefits for productivity and resilience ( Reiss and Drinkwater, 2018 ), but this review focuses on interspecific diversity through intercropping.…”

Oxidative Stability of Oil Obtained from a Low‐Erucic Acid Pennycress (Thlaspi arvense L.) Mutant with Potential for Food Use

“…[ 2 ] Previously only known as a weed, the winter annual pennycress ( Thlaspi arvense L.) has recently received attention in the form of domestication efforts aimed at producing an oilseed cash cover crop suitable for relay or double cropping with corn and soybeans. [ 3 ] Studies have demonstrated numerous ecosystem services provided by pennycress cultivation, including benefits to pollinators by serving as a nutrient source in spring [ 4 ] and efficient carbon sequestration. [ 5 ] Moreover, the limited available data suggest high oil yields (in the range of 29%), [ 6 ] which could make extraction economically feasible.…”