Improving flower attractiveness for pollinators: Study of developmental, morphological and chemical cues in relation to bee foraging

Animal pollinators are vital for life on earth. While human population keeps growing, pollinator populations are dropping, thus threatening food security. In agriculture, the main insect pollinators are bees, by far.The lack of knowledge on how domesticated plants attract and reward bees has hampered the selection of varieties with improved and mutually beneficial crop-pollinator relationships. We propose to investigate flower features, including developmental, morphological and chemical cues, in relation with bee foraging. Elucidating the molecular basis of these processes would not only help sustain yields, but it is key to understand the co-evolution of plants and pollinators.We chose melon as a model system, because it is a strictly entomophilous crop, and because it provides all flower sexual morphs useful to probe plant-insect interactions. ForBees is a multidisciplinary project that integrates molecular genetic analysis and precise phenotyping. First, we will study melon genetic biodiversity with the aim to identify alleles that control nectar-related traits and bee attraction. The comparative analysis of wild accessions, landraces and breeding lines will further test whether domestication led to the loss of useful traits affecting insect visits. Second, we will analyse the gene networks that drive nectar gland development and nectar production. Finally, potential key regulators will be validated genetically. Through this work, we aim to develop a toolbox to tailor the morphology and chemistry of the flowers towards improved bee foraging activities.In addition to research in melon, results from this project, and from previous works, will be translated into neglected crops of the Cucurbitaceae family. These are major food crops in many developing countries, ensuring food security and generating income for poor farmers. Yet, these crops suffer from low fruit set because of partial pollination and would greatly benefit from enhanced breeding tools.