Pollinators enhance the production of a superior strawberry – A global review and meta-analysis

Strawberry (Fragaria x ananasa Duch. ) is the most economically important soft fruit worldwide. While self- and wind-pollination is possible for strawberry, without biotic pollination (animal pollinators, including artificial pollination by humans) rate of strawberry flowers rarely exceeds 60% and thus fruit production is decreased. At a time of widely recognized decline of pollinators and increasing global demand for balanced food, we need a comprehensive understanding of the worldwide valuation of these ecosystem services. In this paper, we use a transparent and systematic review process to detect gaps in the available literature. By applying multilevel meta-analytic models, we quantified the contribution of biotic pollinators and different pollinator types to strawberry fruits. Our review showed that research on strawberry pollination is clearly concentrated in European countries, with limited information for Asia – the largest strawberry producer. Additionally, we detected disproportions across research topics, stressing the need for further research on pollinator preferences between strawberry cultivars and the occurrence of managed and wild bee communities. The overall estimate of pollination benefit to strawberry crops is on average a 25% reduction in fruit weight for plants not receiving a biotic pollination treatment. This benefit is similar regardless of the pollinating species. The mean amount globally (2011–2020) receivable by producers from purchasers due to biotic pollination is 5. 36 billion per year. Moreover, we demonstrated that strawberry plants that are dependent on self- or wind-pollination set on average 43% fewer seeds (fertilized achenes) than biotically pollinated plants. Such a huge reduction in seed set can cause fruit deformation and reduce the commercial value of strawberries. Together, these findings indicate the critical role of biotic pollination in strawberry production and quality. To ensure pollination services in strawberry farms and produce the best-quality fruits, growers should take action to sustain healthy pollinator communities and utilize them with the optimal cultivar.