Influence of mechanical and manual pruning on the incidence of pests in 'Clemenules' mandarins.

Background: In Spain, citrus pruning is usually done by hand, although mechanized pruning is gradually being introduced as a cheaper alternative. The pruning strategy affects the pattern and intensity of sprouting, and the canopy characteristics, and therefore could affect pest control. In this study, the effect of three pruning strategies on the incidence of key citrus pests was analyzed: manual, mechanical (with hedging and topping) and no pruning (control).

Sustainable Use of Pesticide Applications in Citrus: A Support Tool for Volume Rate Adjustment.

Rational application of pesticides by properly adjusting the amount of product to the actual needs and specific conditions for application is a key factor for sustainable plant protection. However, current plant protection product (PPP) labels registered for citrus in EU are usually expressed as concentration (%; rate/hl) and/or as the maximum dose of product per unit of ground surface, without taking into account those conditions. In this work, the fundamentals of a support tool, called CitrusVol, developed to recommend mix volume rates in PPP applications in citrus orchards using airblast sprayers, are presented.

Spray pesticide applications in Mediterranean citrus orchards: Canopy deposition and off-target losses.

Only a portion of the water volume sprayed is deposited on the target when applying plant protection products with air-assisted axial-fan airblast sprayers in high growing crops. A fraction of the off-target losses deposits on the ground, but droplets also drift away from the site. This work aimed at assessing the spray distribution to different compartments (tree canopy, ground and air) during pesticide applications in a Mediterranean citrus orchard.

Effects of spirotetramat on Aonidiella aurantii (Homoptera: Diaspididae) and its parasitoid, Aphytis melinus (Hymenoptera: Aphelinidae).

Laboratory and field studies were conducted to measure the effects of spirotetramat on life stages of California red scale, Aonidiella aurantii (Maskell), and a primary parasitoid, Aphytis melinus DeBach. Organophosphate-resistant and -susceptible populations responded similarly to spirotetramat, suggesting there is no cross-resistance between these insecticide classes. First and second instar male and female A.

Factors influencing the efficacy of two organophosphate insecticides in controlling California red scale, Aonidiella aurantii (Maskell). A basis for reducing spray application volume in Mediterranean conditions.

Background: Because society is seeking ways to lessen the environmental impact of agricultural activity, dose adjustment has become a key issue in current plant protection treatments with high spray application volumes, such as on citrus plants. This work investigates, in field conditions, the factors affecting the efficacy of organophosphate insecticides against California red scale (CRS), Aonidiella aurantii (Maskell), when the delivery rate is decreased. Insecticide rate changes were induced by modifying the spray application volumes of two commercial organophosphate pesticides based on chlorpyrifos and chlorpyrifos-methyl.

Spray deposition and efficacy of four petroleum-derived oils used against Tetranychus urticae (Acari: Tetranychidae).

Petroleum-derived spray oils (PDSOs) offer an interesting alternative to acaricides to control the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), a key pest of clementine mandarins, Citrus reticulata Blanco. However, there is a lack of knowledge on how these products should be used. In this study, we evaluated the efficacy of four PDSOs (Sunspray Ultrafine, Volck Miscible, Texaco D-C-Tron Plus, and Agroaceite) at five concentrations (0.