Bees and Medicinal Plants – Prospective for Entomovectoring

Abstract

Most people are aware that pollinators are in trouble, and with them agricultural products worth more than $200 billion annually (FAO. Pollinators vital to our food supply under threat. http://www.fao.org/news/story/en/item/384726/icode/, 2017). Pollinators are fundamental to maintaining both biodiversity and agricultural productivity, but habitat destruction, loss of flower resources, and increased use of pesticides (particularly neonicotinoids) are causing declines in their abundance and diversity. We constantly search for new bioactive compounds and natural products. We put great efforts into understanding how they work in the human body. We restlessly try to optimize the yield of plant bioactive compounds. Medicinal plants are living organisms and we rely on their effective reproduction to supply these plant substances. Many medicinal plants depend on bees for their seed set. The aim of this study is to evaluate the importance of pollinators for the reproduction of medicinal plants. The plants recognized by the Medicinal Plants Act (using Bulgaria as a model) were classified as spore and gymnosperm plants, anemophilous (wind pollinated) plants and entomophilous (insect pollinated) plants. The plants that require insect vectors for their pollen transport are analyzed further. Entomophilous pollination syndromes are discussed according to the functional morphology and access to nectar and pollen of their “blossoms” (flower or compact inflorescence) in the following basic classes: “dish/bowl”, “bell”, “funnel”, “flag”, and “gullet” as described by Faegri and van der Pijl (1971). Adaptations like spontaneous self-pollination ability and apomixis are also discussed. This analysis only roughly predicts the pollinators. Detailed research results are presented about some medicinal plants. We estimate that about 85% of medicinal plants benefit from insect pollination. This predominant dependence of medicinal plants on insects for pollination is a hazard, but also provides a potential for using these pollen vectors in the context of biological control of insect pests and diseases, i. e. entomovectoring.