Sustainable Management for Spiralling Whitefly, Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae) Infesting Guava and Its Effects on the Natural Enemies’ Complex

Abstract

The spiralling whitefly, Aleurodicus dispersus (Hemiptera: Aleyrodidae), is one of the most notorious insect pests among tropical fruits and vegetables. A common pest management technique is the application of chemical insecticides. However, this has led to environmental degradation, natural enemy reduction, development of pesticide resistance and increased cost of production. This study, therefore, evaluated the efficacy of a sustainable and eco-friendly management strategy against the spiralling whitefly infesting guava (Psidium guajava L). The experiment was carried out with seven treatments replicated five times following the randomized complete block design. The treatments were negative control (T1), 0.8% soybean oil (T2), 1.6% liquid dishwashing (T3), 1.6% neem oil (T4), 0.4% soybean oil + 0.8% liquid dishwashing (T5), 0.8% neem oil + 0.8% liquid dishwashing (T6) and chemical control (Thiamethoxam 25 WG at 2g/L-1) (T7). Results showed that 1.6% liquid dishwashing was superior among treatments against the 1st, 2nd and 3rd nymphal instars with an average mortality of 84.28, 85.22 and 81.81%, respectively. Application of 0.8% soybean oil showed the highest efficacy against the eggs, 4th instar and adult population with an average mortality of 75.50, 81.36 and 93.50%, respectively. Application of these treatments showed no adverse effects on the natural enemies’ complex associated with guava. Integration of other eco-friendly pest management strategies against the invasive spiralling whitefly is recommended for future research.