The Significance of Pollination for Global Food Production and the Guarantee of Nutritional Security: A Literature Review ^†

Abstract

Animal pollination is economically, socially, and culturally relevant. It is responsible for ensuring the production of biofuels, fibers, medicines, building materials, and mainly for the global production of food. The zoochorous pollination syndrome is widely discussed because of the coevolution between plants and animals; so, the pollinators have bioecological characteristics that allow several plants, mainly angiosperms, to complete their reproductive cycles. Thus, this work aims to discuss and synthesize information on studies related to the importance of pollination for global food production and the guarantee of nutritional security, one of the Objectives of the Sustainable Development goals (OSD). A narrative literary review was carried out to obtain data. Pollinators are needed to achieve several OSD, such as Zero Hunger and Life on Earth. Practical activities should be implemented to increase the survival and establishment of these organisms. The commitment of different sectors of society to pollinators is fundamental, and the lack of pollinators leads to losses in productivity and environmental quality.

1. Introduction

Pollination is a term that refers to the transfer of male and female gametes into plants, while pollinators are the means by which gametes travel between plants. The transport of gametes can happen by abiotic and biotic means, such as wind and rain and by the direct action of the plant or animals. The concept has transformed over the past few years to serve as a broad term for structuring a wide range of ecological interactions [1,2,3]. Flowering plants (angiosperms) invariably have no control over how they receive and disperse gametes [4]. However, about 87.5% of angiosperms are dependent on animal vectors for collection, transport, and pollination for reproduction [5].

Animal pollination syndrome dates back to the evolutionary past of mutually beneficial relationships between animals and plants. A long evolutionary history marks the interaction between plants and pollinators, the central hypothesis that explains the current observed ecological interactions comes from mutualistic relationships with benefits for both organisms. When searching for food (foraging), animals that can use floral resources, especially nectar, were rewarded for having access to this resource of high energy value. Over time, this meant a possible preference for certain animals with the capacity to exploit more efficient floral resources for specific plants, which allows for coevolution [6]. This process can lead to extreme ecological interaction with animals using resources unique to a certain plant species, and the plant depending exclusively on this animal for its reproduction. Plants even develop floral traits that are more attractive to animals; for example, in the case of insects, some plants have showy reflective colors at specific lengths for some pollinators, in addition to the nectar mentioned earlier.

Animal pollination is economically [7], socially, and culturally relevant; it is directly related to agriculture and food security [8]. It is responsible for ensuring the production of biofuels [9,10], fibers [7,11], medicines [12], building materials, and mainly for the global production of food [7,13], which is directly dependent on pollination and other factors such as the availability of water, nutrients, soil, and sunlight. The zoochory pollination syndrome is widely discussed due to the evolutionary period between plants and animals; so, the pollinators have bioecological characteristics that allow several plants, mainly angiosperms (±90%), to complete their reproductive cycles. In Brazil, for example, Giannini and collaborators analyzed 141 crops and found 85 dependent on pollination [14]. In 2019, a version of the Thematic Report on Pollination, Pollinators, and Food Production in Brazil of 289 foods was published, with 191 presented studies on the interaction with pollinating organisms, of which 91 presented reliable data on the need for pollinators [15]. Scientists consider that there is a lack of knowledge about the importance of plants and pollination [16], which has objective effects on humanity [8,17], (e.g., loss of production/productivity, decrease in physical and chemical quality aspects, decreased reproduction rate, among others).

Thus, this work aims to discuss and synthesize information on studies related to the importance of the pollination phenomenon for global food production and the guarantee of nutritional security, one of the objectives of sustainable development proposed by the United Nations.

Methodology

This study was carried out through a narrative literary review, collecting data/work carried out from a qualitative approach. All searches were performed in the Google Academic and Science Direct databases, using the keywords: food production AND pollinators OR global trade.

2. Current Overview of Global Food Production

The human population is growing. Projections indicate that by 2050 humanity will demand a significant increase in food production and distribution [18]. However, the land has limited space for occupation and use. Currently, 38% of the terrestrial surface is occupied by agricultural production systems, which is approximately about 5 billion hectares [19]. The productivity of the agricultural system has historically been satiated mainly through area expansion projects and the application of soil fertility conditioning inputs and application of agrochemicals to control animal and plant pests [20]. However, the increase in productive areas solely through expansion does not directly reflect an increase in agricultural productivity [21]. Furthermore, the reduction in and the fragmentation of habitats [22] reduces the resilience of the agroecosystems [23,24] and increases the emission of greenhouse gases [25,26].

Studies indicate that global agricultural production needs to grow [27,28]; estimates indicate values between 70 and 110% to meet the growing demands associated with human use and livestock feeding by the year 2050 [27,29]. Thus, researchers aim to find effective strategies to increase food production in the future [30], one of which is better production in a smaller area [31].

During the last few years, the human population has gone through exponential growth, which imposes demands for resources that, more and more, are becoming scarce. According to the Global Hunger Index, 690 million people are malnourished due to lack of adequate food and access to food [32], which implies the search for new productive areas, increasing pressure on ecosystems with the process of replacement and changes in land-use systems, which in general lead to scenarios of environmental degradation, with the reduction in natural areas and the ecosystem services provided (e.g., nutrient cycling and pollination), which in general reduce the stability of productive areas of the primary commodities and foods [33] and resilience of these areas [23].

Furthermore, the production and consumption of food have been globalized, which gives rise to the concept of virtual resources, that is, resources that are virtually added to internationally traded products.

3. Significance of the Pollinator

Pollination is an ecosystem service, which means that it is considered a consumer good and a service that benefits human beings. This service is responsible for reproducing several plants and crops that are substantially benefited directly or indirectly by pollination by animals such as bees, butterflies, bats, and birds. It is estimated that 75% of all crops profit, to varying degrees, from this type of pollination [34]. Thus, pollination enables the production of food in quantity and quality, which allows food security in several countries, especially in developing countries [35], whose economy is based on agricultural export products.

The decrease in animal pollinators causes severe consequences for the economy and ecosystems. There is a decrease in non-domesticated plants, imbalance in natural environments, decrease in food production and social welfare. The main factors are of anthropogenic origin and are mainly related to land use change, which results in the loss and fragmentation of habitats, in addition to the use of pesticides [31,32], environmental pollution, climate change, dispersal of invasive species, and diseases [36].

Recent studies show the relevance of pollination services related to the diversity of pollinating species; in the most diverse types of food crops (±70%), the volume of agricultural production dependent on animal pollination increased by 300% from 1966 to 2016 [8]. Below we highlight the main pollination-dependent crops (

Table 1. Most common food items in the world, highlighting those that depend directly or indirectly on pollination and/or benefit from pollinating organisms.

Popular Name	Scientific Name	Popular Name	Scientific Name
Coffee	Coffea spp.	Fig	Ficus carica
Soybean	Glycine max	Atemoya	Annona squamosa
Tomato	Lycopersicon spp.	Kiwi fruit	Actinidia deliciosa
Seed cotton	Gossypium spp.	Castor bean	Ricinus communis
Cocoa bean	Theobroma cacao	Broad bean	Vicia faba
Orange	Citrus spp.	Persimmon	Cavanillea philippensis
Watermelon	Citrullus lanatus	Kaki	Diospyros kaki
Passionfruit	Passiflora edulis	Sweet passion fruit	Passiflora alata
Apple	Pyrus malus	Quince	Cydonia spp.
Melonseed	Cucumis melo	Cow peas	Vigna unguiculata
Bean	Phaseolus spp.	Linseed	Linum usitatissimum
Coconut	Cocos nucifera	Lychee	Litchi chinensis
Guava	Psidium guajava	Bean	Phaseolus vulgaris
Peach	Prunus persica	Pomegranate	Punica granatum
Avocado	Persea americana	Cherry	Eugenia uniflora
Sunflower seed	Helianthus annuus	Surinam cherry	Stenocalyx michelii
Papaya	Carica papaya	Tree cotton	Gossypium arboreum
Plum	Prunus spp.	Cambuci	Campomanesia phaea
Annatto	Bixa orellana	Gliricídia	Gliricidia sepium
Tangerine	Citrus reticulata	Brazil nut	Bertholletia excelsa
Cashew nut	Anacardium occidentale	Macadamia	Macadamia integrifolia
Lemon	Citrus spp.	Mombin	Spondias mombin
Guarana	Paullinia cupana	Pumpkin	Cucurbita spp.
Groundnut	Arachis hypogaea	Vanilla	Vanilla spp.
Peppers	Capsicum annuum	Soursop	Annona muricata
Cupuaçu	Theobroma grandiflorum	Adesmia	Adesmia latifolia
Acerola	Malpighia emarginata	Araticum	Annona crassiflora
Pear	Pyrus communis	Apricot	Prunus armeniaca
Oil palm	Elaeis guineensis	Strawberries	Fragaria spp.
Almond	Amygdalus communis	Mango	Mangifera indica
Eggplant	Solanum melongena

Adapted from: Klein, 2007; Giannini, et al., 2015; Reilly, Jr. et al., 2020.

).

The quality of the fruit’s flavor, quality, yield, and nutritional aspects may be linked to the quality of pollination. In a study with strawberries, self-pollination greatly affected production, but animal and manual pollination did not differ in terms of fruit quality. However, manual pollination is often a paid service, especially for large production areas. Hence, animal pollination attends to physiological processes that can result in cheaper fruit and a high-quality standard [37].

For other vegetables, pollination can favor various ways of maintaining the quality of the fruit, seeds, and crops [38], for example, jabuticaba (Plinia sp.). Even in self-compatible species for pollination, the presence and action of a pollinating organism are necessary, which allows an intensification of fruiting [39] (Figure 1), increasing its added value and productivity.

Due to removing natural areas to transform them into agricultural production areas, we have the loss of animal diversity and, within it, the pollinators. Agricultural landscapes devoid of high crop diversity imply a drastic reduction in bee species [39]. These groups, as already discussed, have different ecological roles and environmental services such as pollination of vegetables, fruits, vegetables, among others, that are of fundamental importance for the survival of humans (food) and other animals in the food chain.

According to the Food and Agriculture Organization of the United Nations [40], it is estimated that some species of bee pollinate approximately 73% of plant species cultivated in the world, 19% by flies, 6.5% by bats, 5% for wasps, 5% for beetles, 4% for birds, and 4% for butterflies and moths. Given the importance of this environmental service, beekeepers saw pollination by hives as an essential technique to increase agricultural production and an investment opportunity to rent bees for income generation purposes.

In many countries around the world, such as the USA and countries in Europe, beekeeping began to have pollination as its primary goal, a highly profitable business, making honey a byproduct. This service is an alternative to minimize the effects of the potential natural disaster of the lack of these pollinators globally, which interferes with the production of various foods. The methodology consists of transporting the hives to planting areas in times of flowering, where they can remain for a period of up to three months, ensuring more significant and better productivity [41].

Research shows that when using bees in agricultural cultivation areas, there is an increase in production, such as in apple, cherry, watermelon, pumpkin, and blueberry crops, with economic values for these productions being 1.06 billion, 177 million, 146 million, 101 million, and 50 million dollars, respectively [42]. Thus, the importance of bees for the economic valuation of crops and the need to maintain the biodiversity of pollinating organisms through the maintenance and restructuring of habitats to remain in the environment to help even more in production is noticeable.

4. Final Considerations

Animal pollinators are organisms that provide essential services at ecosystem levels that directly affect the economy and human wellbeing. Thus, as much as the production and trade of food in the world involves different factors and interests, a traditional paradigm shift is necessary. There is a perception that it is utopian to aim to achieve several Sustainable Development Goals of the United Nations (Zero Hunger and Life on Land), but we are optimistic.

In order to leverage pollination services, practical activities must be implemented to increase the survival and establishment of these organisms, which include practical actions such as increasing habitats, preserving portions of natural environments, and banishing harmful pesticides. Most farmers and society generally are not aware of the socioenvironmental and economic value of pollinating agents in terms of food production and several other factors. Nevertheless, there is a need for broad dissemination programs about their importance for humanity and nature for this to be possible.

There is increasingly a scenario of commitment on the part of companies, organizations, and studies that are elucidating quantitatively and qualitatively the role of pollinators in maintaining and balancing terrestrial ecosystems for social wellbeing and the economy. The current perception is that there is much to be done. However, it is increasingly important to note that there is interest in having public and private institutional policies to preserve and pollinate organisms. The lack of these regulatory and compensatory stimuli can invariably lead to losses in productivity and environmental quality.