Insecticidal activity of plant extracts Brevicoryne brassicae (L. 1758) (Homoptera: Aphididae) on kale

Abstract

Brevicoryne brassicae (L.) is an important pest associated with the genus Brassica (L.), being considered the key pest of the kale in Brazil. The objective of this study was to evaluate the insecticidal activity of hydroalcoholic extracts from different plants on B. brassicae mortality. The design was completely randomized, containing eight treatments, being: T1: distilled water (control); T2: hydroalcoholic extract of garlic bulb (Allium sativum); branches T3: ginger rhizome (Zingiber officinale); T4: neem leaves (Azadirachta indica); T5: rust leaves (Ruta graveolens); T6: cinnamon leaves (Cinnamomum verum); T7: leaves + branches of soursop (Annona muricata) and T8: leaves + branches of sugar apple (Annona squamosa), with ten replicates. Three nymphs were deposited on 5 cm diameter leaf cauliflower, individualized in Petri dishes of 9 cm in diameter containing a cotton layer moistened with distilled water. With the aid of a hand spray, the insects received 2 mL-1 of the treatments per petri dish. The plates were closed with clear plastic film and stored in B.O.D at 26.0 ± 1.0 ° C and RH of 70 ± 10%. After 24 hours the number of dead nymphs were counted on the leaf disc and off the disk. Hydroalcoholic extracts hydroalcoholic extracts of garlic bulb; ginger rhizome; neem sheets; rue sheets; cinnamon leaves; leaves + branches of soursop and leaves + branches of sugar apple have insecticidal activity on B. brassicae mortality. No repellency was observed on the pest from the extracts.