In their research based on the statistical method meta-analysis, Elena Gazzea and Lorenzo Marini, researchers from the University of Padua, and Péter Batáry, a scientific advisor at the ELKH Centre for Ecological Research (CER), quantified the impact of natural pollinators on crop quality for the first time at the global scale. The results show that animal pollination plays a crucial role in determining the quality of agricultural production. Fruits pollinated by animals are on average 23 percent higher in quality, indicating that crop quality depends on the presence of pollinating animals to a significant extent, nearly one-fourth. The paper presenting the research was published in the prestigious scientific journal Nature Communications.
Image 1. Pollination of apples by honeybees (Photo: Elena Gazzea).
Pollinating organisms are essential for the reproduction of numerous plant species, including many used in human nutrition, such as fruits and vegetables. In temperate climates, pollinators are primarily insects, including bees, butterflies, various dipterans such as hoverflies, and some beetles, whereas in tropical and subtropical regions, this group also includes birds, bats, and some additional mammals. Over the past decades, the diversity and abundance of many pollinator species have decreased worldwide, giving rise to the phenomenon known as pollinator decline or pollination crisis. Thus, scientific efforts have focused on quantifying these organisms' significance in agriculture, leading to numerous experimental studies on their impact on yield, production stability, and crop quality.
Within the research Global Meta-analysis Shows Reduced Quality of Food Crops under Inadequate Animal Pollination, the researchers aimed to quantify the impact of pollinators on crop quality for the first time globally. They applied the statistical method meta-analysis, which enabled the quantitative synthesis of the literature on the subject.
Image 2. Aesthetic shape and size imperfections of strawberries resulting from inadequate animal pollination (Photo: Elena Gazzea).
The data was collected through systematic literature search in the main scientific databases, using data from 190 independent studies conducted in 48 countries worldwide and involving 48 different crops. The effect of animal pollination was quantified by comparing the differences in quality – shape, size, appearance, taste, and nutritional properties – between crops cultivated with and without pollinators.
The results show that animal pollination plays a crucial role in determining the quality of agricultural production. Fruits pollinated by animals are, on average, 23 percent higher in quality, indicating that crop quality depends on the presence of pollinating animals to a significant extent, nearly a quarter.
Image 3. Examples illustrating how the effects of pollinators on crop quality are examined in research experiments. From left to right: exclusion of pollinators, open animal pollination, manual pollination (Photo: Elena Gazzea).
Animal pollinators positively influence the sensory characteristics of fruits and vegetables, such as their shape, size, and post-harvest storability while contributing less to their nutritional qualities and taste. The benefits of animal pollination on quality are independent of geographical regions and pollinator species. Data analyses have also revealed signs of suboptimal pollination, potentially deriving from pollinator decline in agricultural landscapes, endangering crop quality. However, in general, using pollinators like honeybees sustains the highest quality fruit and vegetable cultivation.
"The results of our study have very important implications for the agricultural and food industry," explains Péter Batáry, one of the study's authors. "The quality of unprocessed foods, such as fruits and vegetables, is based on standards primarily related to their appearance and storability. Due to suboptimal pollination, fruit and vegetable crops deviating from normality can impact the entire agricultural production chain, from the income of agricultural producers to the decisions of consumers whether to purchase the product or not," he adds. Therefore, cultivating imperfect and short-lasting fruits increases the waste of nutrient-rich foods and unnecessarily burdens agricultural areas to compensate for the lack of production of satisfactory quality for the agricultural and food market.
"The global decline of pollinators endangers not only crop yields and their spatial and temporal stability but also the quality of agricultural production. The connection between animal pollination and food waste has been largely overlooked by agricultural and food industry policies, despite its significant economic, societal, and environmental implications, especially in an era where the consumption of nutrient-rich foods is suboptimal worldwide," explains Elena Gazzea, the lead author of the study.
Publication:
Gazzea, E., Batáry, P. & Marini, L. (2023). Global meta-analysis shows reduced quality of food crops under inadequate animal pollination. Nature Communications 14: 4463. DOI: 10.1038/s41467-023-40231-y