By: Amber Floyd
Biological Science 101
Prof. Karen Baracskay
The demand for commercial shipments of large volume, high-quality invertebrate biological control agents for augmentative bio control in outdoor crops far exceeds the current supply of bio control agents needed for the escalating demand in North America (Hale, 2003). Pest resistance to chemical pesticides, enlightened growers, public pressure, government regulations, and expanded production of organic and pesticide-reduced crops are the driving forces behind these demands (Hale, 2003). Augmentative bio control, historically, has been more successful in greenhouse vegetable production than outdoor crops; however, there have been clear cases where it was effective, both in terms of suppression relative to target densities or pesticides, and economic considerations (Hale, 2003). This paper will focus on the limitations and advantages of augmentative biological control (ABC) and its predicted usefulness.
Biological pest control is the use of living organisms to control pests such as insects, mites, weeds and plant diseases (Wiki, 2013). Relying on natural mechanisms like predation, herbivory, pathogens and parasitism, bio control agents are quite often the natural enemy of a pest; parasites and predators are used to reduce insect and other animal pests while herbivores are used to control weeds (Wiki, 2013). Biologically based pest management typically involves an active management role from humans. Although forest and agricultural pests are the main targets of bio control, threats to human health such as mosquitoes and certain weeds in the environment are targets as well (Wiki, 2013). Often bio control operates as an alternative to pesticides and other pest management systems, but can be incorporated in an integrated pest management system (Wiki, 2013). Techniques based on physiology, biochemistry, genetics, animal behavior, and other scientific disciplines paired with the knowledge of an ecology of a pest and it's bio control agents are typically required for the successful practice of bio control (Wiki, 2013). Biological pest control can be divided into three basic types: importation, augmentation, and conservation. Biological Control Approaches
Importation bio control is often referred to as "classical bio control." Many species of pests are not indigenous to where they are problematic (Chang, 2005). Controlling a pest by importing a species that would naturally consume that pest in its indigenous range is one of the earliest scientifically documented bio control successes (Chang, 2005). Determining the origin of an introduced pest and then collecting the appropriate natural enemies of that pest is what the process of importation entails (Chang, 2005). To ensure that a selected natural enemy will work, it is passed through a rigorous assessment and then a testing and quarantine process is completed (Chang, 2005). The selected natural enemy is mass produced and then released after passing all tests (Chang, 2005). Indigenous to Australia, where it is not considered a pest, the cottony cushion scale was considered a serious pest by 1886 after being discovered on citrus trees in California in 1868. Importation of parasites and predators from Australia to California such as the Vidalia beetle (Rodolia cardinalis) to control the scale began in 1887; within two years of introduction, the cottony cushion scale was under control (Chang, 2005). This is a notable example of importation bio control.
Conservation bio control is the conservation of existing natural enemies by modifying the environment to protect, preserve, and enhance bio control agents that were originally released through importation or augmentation, or are indigenous to the area (Chang, 2005). Conservation bio control can be cost effective and simple because the natural enemy is...