DefinePK

Research Objective

To assess the pollinator community of onion (Allium cepa L.) and identify pollinators contributing to higher onion seed production.

Methodology

Field experiment conducted at Muhammad Nawaz University of Agriculture, Multan, Pakistan. Onion variety 'red phulkari' was planted. Pollinator diversity and abundance were assessed by counting and identifying visiting insects on flowering plants. Pollinator foraging behavior was measured by visitation rate and stay time. Pollination effectiveness was evaluated using a pollinator exclusive approach with four pollination treatments (0%, 25%, 50%, 100%). Yield parameters (umbel weight, number of seeds, seed weight) were recorded. Single visit efficacy of major pollinators was also tested. Statistical analysis included paired sample t-test and two-way ANOVA with Tukey's post-hoc test.

Methodology Flowchart

                        graph TD
    A[Experimental Site Setup & Planting] --> B[Pollinator Diversity & Abundance Assessment];
    B --> C[Pollinator Foraging Behavior Measurement];
    A --> D[Pollination Treatments Application];
    D --> E[Yield Parameter Measurement];
    C --> F[Single Visit Efficacy Testing];
    E --> G[Statistical Analysis];
    F --> G;
    G --> H[Conclusion & Implications];                    

Discussion

Syrphid flies were more common pollinators than honeybees in this study, contrasting with some previous findings. Eristalinus aeneus was the most abundant pollinator, followed by Apis florea. While Eristalinus balteatus and Apis florea had high visitation rates, Apis florea had the longest stay time. Single visits by Apis florea resulted in more seeds per umbel compared to dipteran syrphid flies, suggesting Apis florea is a more efficient pollinator for onions. Open pollination significantly increased seed production and umbel weight compared to caged treatments.

Key Findings

Fifteen insect pollinator species from two orders and two families visited onion flowers. Apis florea (dwarf honeybee) was the most frequent bee pollinator, and Eristalinus aeneus (syrphid fly) had the maximum visitation rate. Apis florea also had the longest stay time. Plants with 100% and 50% pollination levels showed significantly higher seed production (44- and 19-times, respectively) compared to 0% pollination. Apis florea demonstrated higher single-visit efficiency in terms of seed yield. Syrphid flies also contributed to onion seed production but were less efficient pollinators.

Conclusion

The study highlights the importance of both hymenopteran (Apis florea) and dipteran (syphid flies) pollinators for onion reproductive success. Apis florea emerged as a particularly effective pollinator, contributing significantly to seed yield. Understanding and conserving these pollinator communities is crucial for optimizing onion seed production.

Fact Check

1. Pollinator Species Count: The study found fifteen insect pollinator species belonging to two orders and two families. (Confirmed in Abstract and Results).
2. Seed Production Increase: Plants with 100% and 50% pollination levels showed 44- and 19-times higher seed production, respectively, compared to 0% pollination. (Confirmed in Abstract and Table 3).
3. Experimental Period: Observations were made from November 2019 to April 2020. (Confirmed in Materials and Methods).

Mind Map