Host Plant Resistance To Insects

Historical overview of host plant resistance; Crop plant and insect diversity; Secondary plant metabolites for insect resistance; Insect - plant interactions; Host plant selection; Mechanisms of resistance; Factors affecting expression of resistance; Screening for insect resistance; Plant resistance and insect pest management; Genetics of resistance to insects; Breeding for resistance to insects.

What is plant resistance to insects? How is plant resistance to insects obtained? How can plant resistance to insects be utilized?

Contributed articles.

Introduction; Insect-plant interaction; Host-plant selection in Phytophagous insects; Mechanisms of resistance; Biochemistry of resistance; Factors affecting expression of resistance; Resistance programme; Genetics of resistance; Plant resistance in pest management.

This comprehensive book is the first illustrated volume to provide detailed discussions of all plant genera regarding techniques developed to evaluate plant resistance to insects. Many of the book's references have never before appeared in a volume on this subject. The authors systematically discuss techniques used to evaluate different types of insect behavior and plant morphological and phytochemical factors responsible for plant resistance and susceptibility to insects.

The earliest land-plants evolved around 450 million years ago from aquatic plants devoid of vascular systems. The diversification of flowering plants (angiosperms) during the Cretaceous period is associated with speciation in insects. Early insect herbivores were mandibulate, but the evolution of vascular plants led to the co-evolution of other forms of herbivory, such as leaf feeding, sap-sucking, leaf mining, tissue borer, gall forming and nectar-feeding. Plant defense against biotic stress is an adaptive evolution by plants to increase their fitness. Plants use a variety of strategies to defend against damage caused by herbivores. Plant defense mechanisms are either inbuilt or induced. Inbuilt mechanisms are always present within the plant, while induced defenses are produced or mobilized to the site where a plant is injured. Induced defense mechanisms include morphological, physiological changes and production of secondary metabolites. Host plant resistance (HPR) is one of the eco-friendly methods of pest management. It protects the crop by making it less suitable or tolerant to the pest. While books on theoretical aspects of HPR are available, an exclusive book on the practical aspects is lacking. There is a wide gap between the theory and the experimental procedures required for conducting studies on plant resistance for the post graduate students and young researchers. A dire need for a book on practical aspects was strongly felt. Initially a practical manual was prepared which eventually evolved into the present book. We hope this book provides information on major aspects of screening crop germplasm, sampling techniques, genetic and biochemical basis of HPR, behavioural studies on pheromone and plant volatiles, and some of the recent approaches in HPR. Further, the references provide the scientific articles and books as additional information to readers and workers alike.

This book reviews and synthesizes the recent advances in exploiting host plant resistance to insects, highlighting the role of molecular techniques in breeding insect resistant crops. It also provides an overview of the fascinating field of insect-plant relationships, which is fundamental to the study of host-plant resistance to insects. Further, it discusses the conventional and molecular techniques utilized/useful in breeding for resistance to insect-pests including back-cross breeding, modified population improvement methods for insect resistance, marker-assisted backcrossing to expedite the breeding process, identification and validation of new insect-resistance genes and their potential for utilization, genomics, metabolomics, transgenesis and RNAi. Lastly, it analyzes the successes, limitations and prospects for the development of insect-resistant cultivars of rice, maize, sorghum and millet, cotton, rapeseed, legumes and fruit crops, and highlights strategies for management of insect biotypes that limit the success and durability of insect-resistant cultivators in the field. Arthropod pests act as major constraints in the agro-ecosystem. It has been estimated that arthropod pests may be destroying around one-fifth of the global agricultural production/potential production every year. Further, the losses are considerably higher in the developing tropics of Asia and Africa, which are already battling severe food shortage. Integrated pest management (IPM) has emerged as the dominant paradigm for minimizing damage by the insects and non-insect pests over the last 50 years. Pest resistant cultivars represent one of the most environmentally benign, economically viable and ecologically sustainable options for utilization in IPM programs. Hundreds of insect-resistant cultivars of rice, wheat, maize, sorghum, cotton, sugarcane and other crops have been developed worldwide and are extensively grown for increasing and/or stabilizing crop productivity. The annual economic value of arthropod resistance genes developed in global agriculture has been estimated to be greater than US$ 2 billion Despite the impressive achievements and even greater potential in minimizing pest- related losses, only a handful of books have been published on the topic of host-plant resistance to insects. This book fills this wide gap in the literature on breeding insect- resistant crops. It is aimed at plant breeders, entomologists, plant biotechnologists and IPM experts, as well as those working on sustainable agriculture and food security.