Floral Strips Attract Beneficial Insects but Do Not Enhance Yield in Cucumber Fields

Abstract

Natural enemies and pollinators require nutritional and habitat resources that are often not found in conventional agricultural fields. The addition of flowering plants within agroecosystems may provide the resources necessary to support beneficial insects at the local scale. We hypothesized that insect pollinator and natural enemy abundance would increase in cucumber (Cucumis sativus) plots containing flower strips and that the effect would be greatest in the crop rows closest to the flower strips. Three flower treatments were tested: 1) buckwheat (Fagopyrum esculentum), 2) yellow mustard (Brassica hirta), 3) sweet alyssum (Lobularia maritima), and cucumbers as a control. Flowers were planted within a commercial cucumber field in 20-m-long strips in a randomized complete block design with six replications in the 2014 and 2015 growing seasons. Some floral treatments successfully attracted more beneficial insects than others, but the beneficials did not disperse out to the cucumber plants. Cucumber yield was unaffected by flowers with one exception: in 2015, cucumber yield in the sweet alyssum plots were greater than those in plots with no flowers. Our research indicates that adding flowers to cucumber fields to increase services from beneficial insects needs to be further investigated to better understand the effect of factors such as relative flowering strip size.

The Role of Annual Flowering Plant Strips on a Melon Crop in Central Spain. Influence on Pollinators and Crop

“…Nevertheless, the presence of flower strips in our small and commercial plots was not associated with an improvement in melon production or quality. In agreement with our findings, the yield of tomato and pepper [45], cider orchards [43], cucumber [44] or commercial strawberry [47] was not affected either. Only in the experimental farm in 2014, the yield and weight of melons from the control plots was higher, in spite of the fact that the number of visits were equal between the two kinds of plots.…”

“…Probably because wild bee populations need time to colonize new habitats [85], permanent flowering strips in crop fields when possible would also enhance the presence of pollinators in the area over time. However, this initiative seems to be a challenge in annual crops (e.g., melon) in intensive agroecosystems with a rotation period between years [44], because the distance between the flower strip and crop within the farm can exceed its possible area of influence, especially in small bees species, which usually forage within an area of few hundred meters from the nest [86]. Furthermore, pollination services in melon fields could be enhanced by including soil patches, alone or in combination with flowers, with adequate features for Lasioglossum females to build nests (e.g., compact soil almost void of vegetation [77]), because species of this genus are key pollinators of the crop.…”

Kompleksitas lanskap pertanian dan pengaruhnya terhadap keanekaragaman Hymenoptera parasitika

“…Penanaman tanaman berbunga di sekitar tanaman pertanian mampu meningkatkan keberadaan serangga bermanfaat, seperti serangga predator dan parasitoid yang dapat mengurangi kepadatan hama sehingga berdampak pada peningkatan produktivitas tanaman. Sebagai contoh, penanaman tanaman berbunga, seperti sweet alyssum (Lobularia maritime) di lingkungan tanaman mentimun dapat meningkatkan hasil panen dari tanaman mentimun (Quinn et al 2017). sekaligus mengurangi populasi hama pada tanaman pertanian (Pfister et al 2017).…”

On-Farm Diversification in an Agriculturally-Dominated Landscape Positively Influences Specialist Pollinators

“…Agriculture, nature's double-edge sword, can either contribute to biodiversity loss or provide opportunities to support biodiversity (Kremen and Merenlender, 2018). Large-scale agriculture intensification in landscapes, including (semi-) natural habitat loss and agrochemical use, have caused insect pollinator decline (Kremen et al, 2002;Biesmeijer et al, 2006;Carvell et al, 2006;Rundlöf et al, 2008;Brittain et al, 2010;Williams et al, 2010;Dupont et al, 2011;Bartomeus et al, 2013;Grab et al, 2019) whereas diversification practices in agricultural landscapes have been shown to support wild bees by providing nesting and foraging resources (Steffan-Dewenter and Leschke, 2003;Morandin and Kremen, 2013;Sardiñas and Kremen, 2015;Kovács-Hostyánszki et al, 2017;Quinn et al, 2017). On-farm diversification practices that provide spatiotemporal floral resource continuity can support pollinator communities (Westphal et al, 2003;Ullmann, 2015), yet little is known about how it affects the diversity and abundance of rarer specialist bees.…”

“…A small number of studies of on-farm or field-scale diversification practices across space and time demonstrate that increasing floral resources support a more abundant and diverse pollinator community (Kennedy et al, 2013;Pereira et al, 2015;Venturini et al, 2016;Lindborg et al, 2017;Quinn et al, 2017). However, little is known about how diversification at the fieldscale and, thus, greater floral resource diversity, would specifically influence specialist pollinator species of crops.…”