Impact of climate change on insect biodiversity, pest management and food security

Climate change has a range of positive and negative impacts on agriculture. Climate and weather plays a predominant role in crop growth and productivity. All plant processes are sensitive to and can be irreversibly damaged by heat. Elevated temperatures accelerate senescence, reduce the duration of viable leaf and diminish photosynthesis. Environmental stress is the primary cause of crop losses worldwide, reducing average yields for most of the crops by more than 50%. Considering insect populations, we can see that climate change affects in many ways: it can cause a shift in geographical spread, abundance or diversity, it can change the location, the timing and the magnitude of outbreaks of pests and it can define the phenological or even the genetic properties of the species. Long-time investigations of special insect populations, simulation models and scenario studies give us very important information about the response of the insects far away and near to our century. Changes in geographical range and insect abundance will increase the extent of crop losses, and thus, will have a major bearing on crop production and food security. Distribution of insect pests will also be influenced by changes in the cropping patterns triggered by climate change. Major insect pests, such as cereal stem borers (Chilo, Sesamia, and Scirpophaga), the pod borers (Helicoverpa, Maruca, and Spodoptera), aphids, and whiteflies may move to temperate regions, leading to greater damage in cereals, grain legumes, vegetables, and fruit crops. Global warming will also reduce the effectiveness of host plant resistance, transgenic plants, natural enemies, biopesticides, and synthetic chemicals for pest management. Therefore, there is a need to generate information on the likely effects of climate change on insect pests to develop robust technologies that will be effective under global warming and climate change in future.