Aleurocanthus woglumi Ashby conhecida popularmente como mosca-negra-dos-citros é considerada praga quarentenária A2 no Brasil e ocasiona prejuízo em diversas frutíferas, principalmente em citros (laranja, limão e tangerina). Poucas são as pesquisas relacionadas aos seus aspectos biológicos nas condições ambientais brasileiras. Nesse sentido, o objetivo da pesquisa foi verificar a preferência de oviposição e a duração do ciclo de vida de A. woglumi em diferentes hospedeiros. A pesquisa foi conduzida em casa de vegetação, durante o período de março de 2009 a março de 2010. Foram realizados testes de preferência sem chance de escolha em seis hospedeiros, simultaneamente, em períodos de 48 e 72 horas, além da biologia comparada em mangueira e laranjeira. Foram observados nos testes que A. woglumi apresenta preferência por ovipositar nas espécies cítricas (limoeiro, laranjeira e tangerineira), mantendo um padrão de não preferência em cajueiro e goiabeira. Os hospedeiros laranjeira e mangueira não interferiram no ciclo biológico da praga.

This study evaluated the development and reproduction of Ceraeochrysa cubana when fed the citrus blackfly Aleurocanthus woglumi. The study was carried out at the Laboratory of Entomology, Department of Plant and Environmental Sciences, Federal University of Paraíba – Areia/PB. It used a completely randomized design. The study was conducted in climate chambers, regulated to 26 ± 2°C and a relative humidity of 70 ± 10% with a 12 h photoperiod. The treatments were as follows: eggs, nymphs of only the 1st, 2nd, 3rd, or 4th instars, and nymphs of multiple instars (1st, 2nd, 3rd, and 4th instars) of A. woglumi, with eggs of Sitotroga cerealella as a control. The 1st instar of C. cubana lasted 5.8 to 10.7 days, the 2nd instar lasted 6.0 to 13.3 days, and the 3rd instar lasted 8.2 to 18.5 days. The larvae of C. cubana did not survive when the food provided was only the eggs of A. woglumi, since the predator could not eat them. C. cubana, when provided nymphs of multiple instars (1st, 2nd, 3rd, and 4th instars) of the citrus blackfly, had a shorter pre-pupal period and lower longevity than when consuming the eggs of S. cerealella, but the sex ratio and oviposition period were not affected. However, changes occurred in the pre-oviposition period, the total number of eggs, and the number of viable eggs.

Citrus BlackFly (CBF) always represented a threat to Brazil. The impact of the introduction in Brazil of the CBF has led to serious economic and environmental consequences. In this chapter, we will show relevant information on biological aspects, history of occurrence, and impact of CBF on Citrus in Brazil; data about dynamics populations and spatial distribution patterns and dependence will be presented. We are intending to emphasize in this chapter the main challenges and opportunities of some important tactics to promote sustainable management of CBF in citrus, such as: (i) biological control, (ii) chemical and others methods, and (iii) induced resistance.

No abstract

Introduction. Citrus trees in Brazil are often attacked by the blackfly, Aleurocanthus woglumi Ashby. The induction of resistance to control this pest is required to maintain the sanitary and nutritional quality of the crop. The aim of this study was to evaluate the potential of silicon in the form of potassium silicate (K 2 SiO 3 ) to modify the activity of enzymes involved in the defence of Citrus reticulata and to find any correlation between the activity of these enzymes and the development of A. woglumi. Materials and methods. The study was conducted in a greenhouse using seedlings of C. reticulate cv. 'Dancy' in the following one-application treatments: T 1 : Infestation with A. woglumi and no K 2 SiO 3 (control, "C"); T 2 : No A. woglumi and no K 2 SiO 3 (absolute control "AC"); T 3 : 17 g L −1 K 2 SiO + A. woglumi, T 4 : 35 g L −1 K 2 SiO + A. woglumi; T 5 : 52 g L −1 K 2 SiO + A. woglumi; and T 6 : 70 g L −1 K 2 SiO + A. woglumi. To perform the enzymatic analyses, one leaf was removed separately from each mandarin seedling after 10, 30, 50, 70, and 90 days of continuous feeding of A. woglumi. The activity of peroxidase, polyphenol oxidase and phenylalanine ammonia-lyase was assessed. Results and discussion. The correlation between peroxidase activity and A. woglumi development was positive. The peroxidase and polyphenol activities indicated strong induction of plant defences against A. woglumi. The increase in peroxidase and polyphenoloxidase activity revealed the induction of synthesis of compounds for plant defence against A. woglumi, but this effect depended on the time of A. woglumi feeding and on the concentration of silicon. Conclusion. Silicon was shown to be an elicitor that potentiates the defence mechanisms of C. reticulata to A. woglumi.Keywords: Brazil / mandarin (Citrus reticulate) / blackfly (Aleurocanthus woglumi) / resistance inductor / peroxidase / polyphenol oxidase / phenylalanine ammonia-lyase Résumé -Résistance aux aleurodes noires des agrumes induite par le silicate de potassium dans les semis de mandarinier (Citrus reticulata). Introduction. Les agrumes au Brésil sont fréquemment attaqués par des aleurodes (Aleurocanthus woglumi Ashby). L'induction de résistance pour lutter contre ce ravageur est nécessaire pour maintenir la qualité sanitaire et nutritionnelle de la récolte. Le but de cette étude était d'évaluer le potentiel du silicium sous la forme de silicate de potassium (K 2 SiO 3 ) dans la modification de l'activité des enzymes impliquées dans la réaction de défense du mandarinier (Citrus reticulata), et aussi de trouver une corrélation entre l'activité de ces enzymes et le développement des aleurodes. Matériel et méthodes. L'étude a été menée en serre en utilisant des plants de mandarinier cv. Dancy. Les traitements suivants ont été appliqués : T 1