Field Experiments of Pollination Ecology: The Case of Lycoris sanguinea var. sanguinea

To reveal the pollinator effectiveness of a given plant species, multiple methods of field experiments have been developed. This study demonstrates the basic methods of field experiments for pollination ecology using the case study of Lycoris sanguinea var. sanguinea and the novel pollination mechanism, breaking-bud pollination.

Transcript

The overall goal of this experiment is to investigate the pollinators of Lycoris sanguinea, variety sanguinea, and their pollination abilities. This method can help researchers in the pollination ecology field. For example, in the decreasing of observers around the time of the will focus on specific pollinators'effect per plant.

The main advantage of this technique is that it facilitates the investigation of floral visitor species and frequencies for analysis of specific visitors'flower pollination efficiency. For floral visitor pre-observation first decide which target individuals in each area will be observed during the same time interval. Next, select 5 to 10 freshly opened flowers who are breaking buds as target flowers, and begin the visual observation for the period of an entire day, as the flowers can be visited by various pollinators in different time ranges.

On the recording sheets, record the species name of each floral visitor, and the time of each visitation per hour, per flower. Closely observe whether floral visitors touch the anthers and/or stigmata. If they do, record the visitors as pollinators.

To capture the floral visitors for their identification and preservation, use a handmade aspirator. Then kill the trapped visitors quickly with ethyl acetate and preserve them in a plastic tube with 100%ethanol. At the end of the observation period, use the morphological features of the visitors to identify the specific names of the specimens.

Select the target flowers as just demonstrated. Then fix the video cameras to tripods and set the tripods approximately 50 centimeters away from the individual targets. Confirm the appropriate focus and light quantity on the screen displays of each target.

Then begin the visual observation and video filming for the appropriate time zones as estimated by the pre-observations. Identify the species names of the visitors and pollinators. At the end of the observation period, check the video clips and note the species'names and their visit times in the same way as for the pre-observation.

For a bagging experiment, select 30 individuals per treatment that have no damage from herbivores or from a severe environment. Label the target flowers in the field. Then, taking care not to touch the anthers or stigmata, bag the flowers with a bag with 0.5 to 1 millimeter mesh holes.

Use supports to keep the individuals upright as necessary, and use a wire to carefully fix the bags to the flowers. Then, adjust the positions of the flowers to prevent contact and pollen depositions between the different stigmata to reject the influences from before the cage establishment. Afterwards, cover the target plant individuals with prepared cages.

Using iron poles, attach the cages firmly to the ground to prevent entry by visitors between the cage bases and the ground. At the end of the flowering season, collect all of the caged and labeled flowers by cutting and separating them from the maternal individuals. Preserve each labeled sample separately to prevent contamination.

Then check for the presence or absence of a fruit set on each labeled flower, recording the seed numbers of each fruit in the case of setting fruit. In this representative experiment, floral visitor observations revealed that most of the visitors to all five study sites were individuals of the small bee species Lasioglossum Japonicum, with a visitation ratio of more than 90%at three sites. In contrast, the ratios of the second most frequent visitor, Amegilla Florea, were lower than 10%in these fields.

Both bee species also touched the stigmata of visited flowers and were recorded as pollinators. At one site, the visitation frequencies of small bees recorded by visual observations were significantly higher than those recorded by video. The breaking bud treatment of bagged or caged flowers demonstrates the pollination ability of small bees visiting breaking buds with a higher fruit set than the auto self-pollination observed in this experiment, indicating the presence of pollen deposition by small bees to stigmata at the breaking bud stage.

Comparing the fruit and seed sets between the treatments reveals the reproductive traits of Lycoris sanguinea, variety sanguinea, which is predominantly animal-pollinated, with partially pollen-limited conditions. Further, these comparisons also suggest that the plant in this experiment has a self-compatibility consistent with previous reports. Moreover, comparisons of the other treatments confirm the pollination abilities of breaking bud pollination in Lycoris sanguinea, variety sanguinea.

Once mastered, the plant cage technique can be performed on most growing plants for a variety of visitors. For the pollinator with patience, pre-research of the floral visitors, applying suitable recording techniques and selection of optimal are essential for accurate data collection. The introduction of recording equipment reduces incidence of possible human recording errors, such as over-observation of floral visitors.

Following these procedures as a method, like molecular analysis using polymorphic micro saccharide markers can be performed to answer additional questions about pollinator-mediated gene flow between individuals. After watching this video, you should have a good understanding of how to record the interactions of target plants and pollinators, through observation of floral visitors and estimations of their pollination efficiencies.

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Journal (Environment)

Journal (Environment)

Field Experiments of Pollination Ecology: The Case of Lycoris sanguinea var. sanguinea

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