Self-Fertilization, Inbreeding, and Yield in Alfalfa Seed Production

Jiang

Zhao

et al. 2023

Sci Rep

Self Cite

In insect-pollinated plants, the foraging behavior of pollinators affects their pattern of movement. If distinct bee species vary in their foraging behaviors, different models may best describe their movement. In this study, we quantified and compared the fine scale movement of three bee species foraging on patches of Medicago sativa. Bee movement was described using distances and directions traveled between consecutive racemes. Bumble bees and honey bees traveled shorter distances after visiting many flowers on a raceme, while the distance traveled by leafcutting bees was independent of flower number. Transition matrices and vectors were calculated for bumble bees and honey bees to reflect their directionality of movement within foraging bouts; leafcutting bees were as likely to move in any direction. Bee species varied in their foraging behaviors, and for each bee species, we tested four movement models that differed in how distances and directions were selected, and identified the model that best explained the movement data. The fine-scale, within-patch movement of bees could not always be explained by a random movement model, and a general model of movement could not be applied to all bee species.

Section: Methodsmentioning

confidence: 99%

Bee species perform distinct foraging behaviors that are best described by different movement models

Jiang

Zhao

et al. 2023

Sci Rep

Self Cite

“…Seeds collected from the bumble bee and leafcutting bee trials were tested for the presence of the GR gene using a seedling phenotypic assay, combined with test strips [28]. The phenotypic assay is a modification of a protocol originally developed by [29] to distinguish between conventional and GR seedlings.…”

Section: Detection Of the Glyphosate Resistance Genementioning

confidence: 99%

“…Thereafter, seedlings were watered with a 0.1% Plant Preservative Mixture (PPM, Caisson Laboratories, Inc., Smithfield, UT) deionized water solution to prevent fungal growth. At the end of the 14-day period, seedlings were evaluated for traits associated with glyphosate resistance, such as increased root length, smaller root width, and development of secondary roots or root hair [28,29]. When a seedling was categorized as positive using the phenotypic assay, the presence of the GR gene in the seedling was confirmed using a test strip [16].…”

Section: Detection Of the Glyphosate Resistance Genementioning

confidence: 99%

Differential ability of three bee species to move genes via pollen

Fragoso¹,

2023

PLoS ONE

Since the release of genetically engineered (GE) crops, there has been increased concern about the introduction of GE genes into non-GE fields of a crop and their spread to feral or wild cross-compatible relatives. More recently, attention has been given to the differential impact of distinct pollinators on gene flow, with the goal of developing isolation distances associated with specific managed pollinators. To examine the differential impact of bee species on gene movement, we quantified the relationship between the probability of getting a GE seed in a pod, and the order in which a flower was visited, or the cumulative distance traveled by a bee in a foraging bout. We refer to these relationships as ‘seed curves’ and compare these seeds curves among three bee species. The experiments used Medicago sativa L. plants carrying three copies of the glyphosate resistance (GR) allele as pollen donors (M. sativa is a tetraploid), such that each pollen grain carried the GR allele, and conventional plants as pollen recipients. Different foraging metrics, including the number of GR seeds produced over a foraging bout, were also quantified and contrasted among bee species. The lowest number of GR seeds set per foraging bout, and the GR seeds set at the shortest distances, were produced following leafcutting bee visits. In contrast, GR seeds were found at the longest distances following bumble bee visits. Values for honey bees were intermediate. The ranking of bee species based on seed curves correlated well with field-based gene flow estimates. Thus, differential seed curves of bee species, which describe patterns of seed production within foraging bouts, translated into distinct abilities of bee species to move genes at a landscape level. Bee behavior at a local scale (foraging bout) helps predict gene flow and the spread of GE genes at the landscape scale.

“…Medicago (Fabaceae), also called alfalfa or lucerne, is a perennial legume with owers arranged in a cluster or raceme. It is a self-compatible plant with fairly high outcrossing rate (5.3-30%) 43 , and it requires insect visits for seed production 44 . No plant material was collected for this study.…”

Section: Plant Species and Pollinatorsmentioning

confidence: 99%

Bee species perform distinct foraging behaviors that are best described by different movement models

Jiang

Zhao

et al. 2022

Preprint

Self Cite

In insect-pollinated plants, the foraging behavior of pollinators affects their pattern of movement. If distinct bee species vary in their foraging behaviors, different models may best describe their movement. In this study, we quantified and compared the fine scale movement of three bee species foraging on patches of Medicago sativa. Bee movement was described using distances and directions traveled between consecutive racemes. Bumble bees and honey bees traveled shorter distances after visiting many flowers on a raceme, while the distance traveled by leafcutting bees was independent of flower number visited by a focal bee. Transition matrices and vectors were calculated for bumble bees and honey bees to reflect their directionality of movement within foraging bouts; leafcutting bees were as likely to move in any direction. Bee species varied in their foraging behaviors, and for each bee species, we tested four movement models that differed in how distances and directions were selected, and identified the model that best explained the movement data. The fine-scale, within-patch movement of bees could not always be explained by a random movement model, and a general model of movement could not be applied to all bee species.