Prediction of the potential geographic distributions and risk assessment of four trade impacting invasive insect pests in Australia and China

This thesis explores biological invasion through the potential pest distribution and risk analysis of tomato potato psyllid (TPP), Bactericera cockerelli; fall armyworm (FAW), Spodoptera frugiperda; Bactrocera bryoniae; and Bactrocera neohumeralis. Through better understanding of the pest distribution and risk analysis agricultural management policies can be implemented, and containment and eradication actions taken. The TPP is a psyllid native to North America that has recently invaded Australia. The potential for economic losses accompanying invasions of TPP and its associated bacterial plant pathogen Candidatus Liberibacter solanacearum (CLso), has caused much concern. Here, we employed ecological niche models to predict environments suitable for TPP/CLso on a global scale and then evaluated the extent to which global potato cultivation is at risk. A total of 86 MaxEnt models were built using various combinations of settings and climatic predictors, and the best model based on model evaluation metrics was selected. Climatically suitable habitats were identified in Eurasia, Africa, South America, and Australasia. Intersecting the predicted suitability map with land use data showed that 79.06% of the global potato production, 96.14% of the potato production acreage in South America and Eurasia, and all the Australian potato production are at risk. The information generated in this study increases knowledge of the ecology of TPP/CLso and can be used by government agencies to make decisions about preventing the spread of TPP and CLso across the globe. Fall armyworm (FAW), S. frugiperda is native to the Americas and it has rapidly invaded 47 African countries and 18 Asian countries since the first detection of invasion into Nigeria and Ghana in 2016. It is regarded as a ‘super pest’ based on its host range (at least 353 host plants), its inherent ability to survive in a wide range of habitats, its strong migration ability, high fecundity, rapid development of resistance to insecticides/viruses and its gluttonous characteristics. In order to better understand the seasonal geographic distributions of S. frugiperda, we employed ecological niche models of MaxEnt to predict potential year-round breeding and seasonal distribution for S. frugiperda on a global scale and in Australia. A total of 74 MaxEnt models were built using various combinations of regularization multiplier, feature class and climatic variables, and the best model based on model evaluation metrics was selected, with an evaluation of dominant climatic factors that control its distribution. The results suggest that the temperature factor was the most important variable affecting the seasonal distribution of S. frugiperda. No matter where in the world, the year-round breeding distribution model predicted smaller portions of fall armyworm's ranges than the seasonal model. S. frugiperda had a high remaining invasion potential in Australia, posing a significant threat to its biosecurity, food security and agricultural productivity. Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive fruit flies and considered major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific. Ecological niche modelling MaxEnt was employed to predict the potential geographic distribution of B. bryoniae and B. neohumeralis across the world and particularly in China with the occurrence data of these two species. B. bryoniae and B. neohumeralis exhibit similar potential geographic distribution ranges across the world and in China, and included southern Asia, the central and the southeast coast of Africa, southern North America, northern and central South America, and Australia. While within China, most of the southern Yangtze River area was found suitable for these two species. Notably, southern China was considered to have the highest risk of B. bryoniae and B. neohumeralis invasions. Our study identifies the regions at high risk for potential establishment of B. bryoniae and B. neohumeralis in the world and particularly in China and informs government officials to develop policies for inspection and biosecurity/quarantine measures to prevent and control their invasion

Migration Dynamics of Fall Armyworm <i>Spodoptera frugiperda</i> (Smith) in the Yangtze River Delta

The Yangtze River Delta, located in East China, is an important passage on the eastern pathway of the northward migration of fall armyworm Spodoptera frugiperda (Smith) in China, connecting China’s year-round breeding area and the Huang-Huai-Hai summer maize area. Clarifying the migration dynamics of S. frugiperda in the Yangtze River Delta is of great significance for the scientific control and prevention of S. frugiperda in the Yangtze River Delta, even in the Huang-Huai-Hai region and Northeast China. This study is based on the pest investigation data of S. frugiperda in the Yangtze River Delta from 2019 to 2021, combining it with the migration trajectory simulation approach and the synoptic weather analysis. The result showed that S. frugiperda migrated to the Yangtze River Delta in March or April at the earliest, and mainly migrated to the south of the Yangtze River in May, which can be migrated from Guangdong, Guangxi, Fujian, Jiangxi, Hunan and other places. In May and June, S. frugiperda migrated further into the Jiang–Huai region, and its source areas were mainly distributed in Jiangxi, Hunan, Zhejiang, Jiangsu, Anhui and Hubei provinces. In July, it mainly migrated to the north of Huai River, and the source areas of the insects were mainly distributed in Jiangsu, Anhui, Hunan, Hubei and Henan. From the south of the Yangtze River to the north of the Huai River, the source areas of S. frugiperda were constantly moving north. After breeding locally, S. frugiperda can not only migrate to other regions of the Yangtze River Delta, but also to its surrounding provinces of Jiangxi, Hunan, Hubei, Henan, Shandong and Hebei, and even cross the Shandong Peninsula into Northeast China such as Liaoning and Jilin provinces. Trajectory simulation showed that the emigrants of S. frugiperda from the Yangtze River Delta moved northward, westward and eastward as wind direction was quite diverse in June–August. This paper analyzes the migration dynamics of S. frugiperda in the Yangtze River Delta, which has important guiding significance for the monitoring, early warning and the development of scientific prevention and control strategies for whole country

Neonicotinoids and their substitutes in sustainable pest control

ISBN 978-3-8047-4144-7, EASAC / FEAM REPORT (European Academies Science Advisory Council / Federation of Auropean Academies of Medicine

Biological Invasions: Biogeography and Multitrophic Interactions

Species interactions play a prominent role in the establishment and spread of many invasive species. However, rarely are invasions studied in more than a direct pairwise species context, or with consideration to how species interactions can vary biogeographically. I used field surveys combined with common garden and greenhouse experiments to investigate how multitrophic above- and belowground interactions influence plant invasions at large spatial scales. I focused on comparisons between sympatric native and invasive lineages of Phragmites australis, a wetland grass distributed throughout North America. I conducted a field survey to examine support for the enemy release hypothesis in a tritrophic framework. In North America, the invasive lineage of P. australis benefitted from strong local enemy release from introduced Lipara gall-flies relative to the native lineage, attributed to greater vertebrate predation on Lipara infesting the invasive lineage. A complementary common garden experiment revealed that local enemy release of the invasive P. australis lineage from Lipara was driven by local environmental conditions rather than genetic differences between the native and invasive lineages. Moreover, local enemy release was strongest at northern latitudes, generated by genetically based non-parallel latitudinal gradients in Lipara herbivory for the native and invasive lineages. This phenomenon could translate to biogeographic variation in invasion success and is worthy of investigation across a range of invaded systems and species interactions. I also conducted a greenhouse experiment to examine interactive effects of rhizosphere soil biota, interspecific competition, and nutrient availability on performance of P. australis and native Spartina alterniflora. All lineages of P. australis suffered negative impacts from soil biota, suggesting this interaction does not directly facilitate the success of invasive P. australis. However, the most interesting result from this experiment was that soil biota from the invasive lineage negatively impacted S. alterniflora, whereas soil biota from the native lineage had the opposite effect. This type of indirect interaction may result in important implications for invasion success and restoration. In summary, my dissertation highlights the importance of examining biological invasions in a biogeographic and multitrophic context and has broad implications for the understanding and management of biological invasions

Area-wide Integrated Pest Management

Extensive reliance on insecticides reduces biodiversity, contributes to pollinator decline, destroys habitat and threatens endangered species. This book offers a more effective application of the Integrated Pest Management (IPM) approach, on an area-wide (AW) or population-wide (AW-IPM) basis. It addresses the importance of problem-solving research, planning and baseline data collection, integrating tools for appropriate control strategies, and pilot trials. The 48 chapters authored by 184 experts cover advances in genetics, molecular biology, biological control, resistance management, modelling, automated surveillance and unmanned aerial release systems

Area-wide Integrated Pest Management

Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, including non-target species, air, water and soil. The extensive reliance on insecticide use reduces biodiversity, contributes to pollinator decline, destroys habitat, and threatens endangered species. This book offers a more effective application of the Integrated Pest Management (IPM) approach, on an area-wide (AW) or population-wide (AW-IPM) basis, which aims at the management of the total population of a pest, involving a coordinated effort over often larger areas. For major livestock pests, vectors of human diseases and pests of high-value crops with low pest tolerance, there are compelling economic reasons for participating in AW-IPM. This new textbook attempts to address various fundamental components of AW-IPM, e.g. the importance of relevant problem-solving research, the need for planning and essential baseline data collection, the significance of integrating adequate tools for appropriate control strategies, and the value of pilot trials, etc. With chapters authored by 184 experts from more than 31 countries, the book includes many technical advances in the areas of genetics, molecular biology, microbiology, resistance management, and social sciences that facilitate the planning and implementing of area-wide strategies. The book is essential reading for the academic and applied research community as well as national and regional government plant and human/animal health authorities with responsibility for protecting plant and human/animal health

African Handbook of Climate Change Adaptation

This open access book discusses current thinking and presents the main issues and challenges associated with climate change in Africa. It introduces evidences from studies and projects which show how climate change adaptation is being - and may continue to be successfully implemented in African countries. Thanks to its scope and wide range of themes surrounding climate change, the ambition is that this book will be a lead publication on the topic, which may be regularly updated and hence capture further works. Climate change is a major global challenge. However, some geographical regions are more severly affected than others. One of these regions is the African continent. Due to a combination of unfavourable socio-economic and meteorological conditions, African countries are particularly vulnerable to climate change and its impacts. The recently released IPCC special report "Global Warming of 1.5º C" outlines the fact that keeping global warming by the level of 1.5º C is possible, but also suggested that an increase by 2º C could lead to crises with crops (agriculture fed by rain could drop by 50% in some African countries by 2020) and livestock production, could damage water supplies and pose an additonal threat to coastal areas. The 5th Assessment Report produced by IPCC predicts that wheat may disappear from Africa by 2080, and that maize— a staple—will fall significantly in southern Africa. Also, arid and semi-arid lands are likely to increase by up to 8%, with severe ramifications for livelihoods, poverty eradication and meeting the SDGs. Pursuing appropriate adaptation strategies is thus vital, in order to address the current and future challenges posed by a changing climate. It is against this background that the "African Handbook of Climate Change Adaptation" is being published. It contains papers prepared by scholars, representatives from social movements, practitioners and members of governmental agencies, undertaking research and/or executing climate change projects in Africa, and working with communities across the African continent. Encompassing over 100 contribtions from across Africa, it is the most comprehensive publication on climate change adaptation in Africa ever produced