Preface

Plant reproductive ecology is concerned with the adaptive significance of the variation in traits associated with floral biology, pollination, seed dispersal, and seedling establishment. The immobility of plants and their reliance on pollen vectors for mating is the main cause of the diversification of floral traits and pollination systems in flowering plants. This book explores the reproductive diversity of flowering plants in relation to environmental variables. It has direct relevance in agriculture, horticulture, conservation of biodiversity, control of invasive plant species, plant breeding, and biotechnology.

The volume is a compilation of seven chapters written by eminent scientists across the world. Flower symmetry is a key evolutionary innovation of angiosperms and transition from radial to bilateral symmetry is believed to be associated with increased specificity to pollinators, thereby favoring reproductive isolation. Chapter 1 unravels the genetic, phylogenetic, and evolutionary patterns for transition in flower symmetry. Chapter 2 provides an interesting and comprehensive review of the evolutionary transformations of the reproductive structures of angiosperms in light of aromorphosis, allomorphosis, specialization, and reduction, which are the key directions of the evolutionary process.

Pollination is an integral event for the reproductive success of a plant. Chapter 3 focuses on the diversity of pollinators in an agro-ecosystem, the interactions between plants and pollinators, and the threat of declining pollinators. The authors highlight the need for comprehensive management strategies and restoration of pollinators for sustainable agriculture. Chapter 4 reviews the complex breeding system of commercially important Citrus species like mandarin, sweet orange, pummelo, grapefruit, lemons, limes, and citrons and their dependency on pollination services in a global pollinator decline scenario. Chapter 5 discusses the complex interactions and impact of non-native exotic plant communities on native plants and pollinators.

Seed biology is an important aspect of reproductive ecology, as fruits and seeds are the economic products of many of our crop plants. Chapter 6 highlights recent advances in the reproductive ecology of *Medicago sativa* (alfalfa), an important forage legume, in relation to its floral biology, pollination ecology, ovule sterility, inbreeding depression, breeding strategies, seed production, and seed dispersal. Chapter 7 focuses on seed priming, a cost-effective interlinking technology between seed germination and seedling establishment. The authors discuss the relevance of the technique in enhancing seed vigour and seed germination and promoting successful crop stand establishment under extreme climatic conditions and fragile ecosystems.

The book is a useful resource for ecologists, botanists, zoologists, plant breeders, and conservation biologists.

We thank Author Service Manager, Ms. Jasna Bozic, at IntechOpen for her constant support and help in completing this project.
