Most flowering plants can achieve pollination in several different ways. Those that produce pollen and carpels on the same plant may be self-pollinated, but they may also be cross-pollinated by insects or other pollinators. The cape gooseberry (Physalis peruviana) shown here is able to produce seed whether it is self- or cross-pollinated.
Is one type of pollination better for reproductive success than the other?
Researchers conducted controlled experiments to test for effects of different types of pollination on cape gooseberry fruit size and seed production. The types of pollination included self-pollination, cross-pollination by bees, and manual cross-pollination (transferring pollen from one plant to another by hand). Results are shown in the graphs here. Compared to self-pollination, do bees have a significant impact on fruit mass?
How about on seed formation?

Verified step by step guidance

1. Examine the left graph, which shows the fruit mass (in grams) for different pollination methods: self-pollination, bee pollination, and manual pollination.
2. Notice that the fruit mass is highest for bee pollination, followed by manual pollination, and lowest for self-pollination. The asterisk indicates a statistically significant difference between self-pollination and bee pollination.
3. Examine the right graph, which shows the number of seeds per fruit for the same pollination methods.
4. Observe that the number of seeds per fruit is also highest for bee pollination, followed by self-pollination, and lowest for manual pollination. The asterisk indicates a statistically significant difference between self-pollination and bee pollination.
5. Conclude that bee pollination significantly increases both fruit mass and seed production compared to self-pollination, indicating that bee pollination is more effective for reproductive success in cape gooseberry.

Key Concepts

Pollination Types

Pollination is the process by which pollen is transferred from the male anther to the female stigma of flowers, leading to fertilization. There are two main types: self-pollination, where pollen from the same flower fertilizes its ovules, and cross-pollination, which involves pollen from different plants. Cross-pollination often enhances genetic diversity, potentially leading to greater adaptability and reproductive success.

Reproductive Success

Reproductive success refers to the ability of an organism to produce offspring that survive to reproductive age. In flowering plants, factors influencing reproductive success include fruit size and seed production, which can be affected by the type of pollination. Understanding how different pollination methods impact these factors is crucial for assessing the overall fitness of a plant species.

Impact of Pollinators

Pollinators, such as bees, play a significant role in the reproductive success of many flowering plants by facilitating cross-pollination. Studies often measure the effects of pollinators on fruit mass and seed production to determine their effectiveness. The data from experiments can reveal whether pollinators significantly enhance reproductive outcomes compared to self-pollination, providing insights into plant-pollinator interactions.