The wheat stem sawfly (WSS), Cephus cinctus (Hymenoptera: Cephidae), is one of the most important insect pests of wheat in the northern Great Plains region of the United States and Canada, with economic losses exceeding $100 million per year. Traditional pest management strategies including pesticides are generally unsuccessful due to an extended adult flight time and the inaccessible larval stage that feeds within the wheat stem. Research towards integrated pest management strategies based on olfaction has proved promising. However, little is known about the molecular basis of olfaction in this important insect pest. We have identified and annotated 131 members of the major olfactory-related gene families from antennal transcriptome and whole genome sequences, including: 6 odorant binding proteins (OBP), 8 chemosensory proteins (CSP), 53 odorant receptors (OR), 14 ionotropic receptors (IR), 12 carboxylesterases (CCE), 8 gluthatione S-transferases (GST), and 29 cytochrome P450s (P450). Expression levels in the antennae, sawfly bodies, and whole larvae were analyzed using RNA-seq. Gene expression results were used to identify candidate genes for further functional characterization based on higher enriched expression in antennae and/or sex-biased expression in the antennae. These candidate WSS olfactory genes may mediate important pest behaviors and serve as molecular targets for future insect management strategies.

The wheat stem sawfly, Cephus cinctus Norton (WSS), has been a serious pest of wheat in the Northern Great Plains of North America for decades. Host plant resistance has been most consistently effective and is the foundation for integrated pest management of the WSS; therefore, the main objective of this research was to enhance the repertoire of genetic resistance to WSS available for exploitation by wheat breeders through marker-assisted selection (MAS). We used two strategies to achieve our goal. First, we better characterized resistance provided by previously identified quantitative trait loci (QTL). For that, we developed populations of near-isogenic lines (NILs) polymorphic for resistance QTLs on chromosomes 2D (Qwss.msub-2D), 3B (Qss-msub-3BL) and 4A (Qwss.msub-4A.1). Near-isogenic lines were tested greenhouse cage trials and in the field at both WSS-infested and uninfested locations. The Qwss.msub-4A.1 was shown to affect host plant attractiveness to foraging females, but did not change oviposition preference after females landed on the wheat stem. The Qwss.msub-2D and Qss-msub-3BL where shown to be associated with decreased preference for oviposition. The Qss-msub-3BL was also shown to be associated with temporal patterns of stem solidness expression, with the allele derived from the spring wheat cultivar Conan providing decreased infestation, high neonatal mortality, high levels of early stem solidness, and a rapid rate of pith retraction during stem maturation. Together, these studies characterized the effect of each one of these QTLs on WSS resistance. This information will help wheat breeders and entomologists to better integrate management strategies to reduce damage caused by the WSS. Our second strategy, involved the identification of new marker-trait associations for WSS resistance. For that, we used a panel of 244 elite spring wheat lines from North America. By conducting an association mapping study we were able to identify several QTLs for WSS resistance, including QTLs for early and late stem solidness, heading date, stem cutting, and larval mortality. This study showed that improvements in WSS management may be obtained using alleles that already exist in elite germplasm. Collectively, our research provided wheat breeders with a better tool kit for improving resistance to the WSS.

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.

This book is a ready reference on recent innovations in dryland agriculture and reinforces the understanding for its utilization to develop environmentally sustainable and profitable food production systems. It covers the basic concepts and history, components and elements, breeding and modelling efforts, and potential benefits, experiences, challenges and innovations relevant to agriculture in dryland areas around world.

Montana is the fourth largest state in the United States. It includes portions of both the Northern Great Plains and the Rocky Mountains. Vegetation of Montana is diverse, due primarily to the size of the state as well as great topographic relief which provides strong variation in environmental factors. Montana has a relatively large flora for a northern continental region due to being at the intersection of the Cordilleran, Great Plains, and Boreal floristic provinces. This book is a comprehensive field guide to the more than 2,500 species of Montana's vascular plants. It contains descriptions as well as habitat and distribution information based on specimens housed at the state's two major herbaria. Portraits or illustrations of diagnostic structures are provided for nearly one-third of the species.

Their natural enemies largely determine the population size and dynamic behavior of many plant-eating insects. Any reduction in enemy number can result in an insect outbreak. Applied biological control is thus one strategy for restoring functional biodiversity in many agroecosystems. Predators and Parasitoids addresses the role of natural enemies i