Pesticide resistance occurs rapidly in aphids and in a number of reported cases, the use of chemicals has resulted in further destruction than would have occurred without the treatment.
Integrated pest management programmes are becoming the most promising strategies for aphid control. Using aphid predators or parasites in collaboration with yellow sticky roller traps can provide unrivalled control. Each glasshouse has a diverse range of crops, microclimates and other ecological conditions that result in a unique ecosystem. As insects are living organisms they are very susceptible to slight environmental changes and so control strategies that work in one greenhouse may not work so well in another. In collaboration with various growers in different climates and industries, Russell IPM has developed 3 core products in the Optiroll range that are each suited to the array of environments most commonly found to host aphid species. Not all aphids develop wings and thus, sticky roller traps work most effectively in areas where infestations levels are high.
Several studies have demonstrated that yellow is most attractive to aphid pests in greenhouses and polytunnels. Adult winged aphids will be caught on the yellow sticky roll preventing them from feeding and causing further damage. Their wings tend to be spread out on either side of their body. For identification: two distinct dark spots on their wings may be visible and two cornicles should be present at the lower end of their abdomen. Aphids may produce multiple offspring on the sticky roll before they die.
Aphids, including Macrosiphum euphorbiae and Aphis gossypii, are common pests found in glasshouses across the globe. The biggest threat posed by the small greenfly is its ability to transmit plant viruses that affect a range of economically important crops. Secondly, the aphids have a rapid reproductive rate which can lead to heavy and severe infestations. The host range of the common glasshouse aphid is extremely broad and includes fruit, vegetable and fibre crops, ornamentals and flowers.
Damage by aphids is caused by feeding whereby the sap extraction can drain plant nutritional resources quite rapidly. The aphids release secretions during sap extraction from the phloem that can contain pathogenic plant viruses that cause severe damage to the crop. Damage often manifests as curled, dried leaves with occasional yellow spots. Secretions can foster mould development resulting in crop soiling.
Reproduction in Aphids is mainly asexual and is affected by external factors such as nutritional availability, temperature and overcrowding. In glasshouses the females most often produce offspring vivaparously which will then immediately begin feeding from plant sap. Maturity occurs rapidly and winged aphids can occur when infestation levels are extremely high, enabling mobility of the pest to find new plant hosts. Aphids prefer to feed on the underside of young leaves but the entire plant can be used as a feeding point if space is at a minimum.