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The plants extract may be compatible with other management tactics, especially with biologicalcontrol. so the aim of this work was to evaluate the residual effect of several extracts from cedartree (C) and mahogany tree (M) (bark (C), wood (M) and leaf (F); cecropia tree (I) (bark - C andwood - M) and of the pereiro (P) (bark -C), and its possible effects on the adults of the parasitoidTrichogramma galloi(Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cards containingparasitised eggs of Diatraea saccharalis(Fabricius, 1794) (Lepidoptera: Crambidae), or containigeggs that would be submitted to the parasitoid were immersed for 30 seconds in the extracts at 5000μg.mL-1. The number of parasitised eggs and adult emergence of the parasitoid were evaluated.The highest rates of parasitism, up to 60.0%, was obtained by the control treatment, MC, MM, CCand MF, and the treatments that caused a lower percentage of parasitism, IC, IM, PC, CM andCF, respectively. The extracts of different parts of mahogany, which showed a good percentageof parasitism, affected the development of the parasitoid with a low adult emergence. The PCshowed a lower parasitism and emergence. In relation to eggs treated four days after parasitism,it was found that the control treatment had a good average in emergency (98.85%), in the samecategory of treatments IM, CF and CC, respectively. The CC extract was more selective and the PCwas the least selective for T. galloi., Os extratos vegetais podem ser compatíveis com outras táticas de manejo, principalmente com o controle biológico. Desta forma, objetivou-se neste trabalho avaliar o efeito residual dos extratos de Cedrela fissilis Vell. (Meliaceae) cedro (C) e Swietnia macrophylla King Vell. (Meliaceae) mogno (M) (casca- C), madeira (M) e folha (F); Cecropia pachystachya (Cecropiaceae) imbaúba (I) (casca - C e madeira - M) e Aspidosperma pyrifolium Mart. (Apocynaceae) pereiro (P) (casca - C), sobre adultos do parasitoide Trichogramma galloi (Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cartelas contendo ovos de Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) parasitados, ou que seriam submetidos aos parasitoides, foram imersas por 30 segundos nos extratos a 5000 mg.mL-1. Avaliaram-se o número de ovos parasitados e a emergência dos adultos do parasitoide. As maiores taxas de parasitismo, acima de 60,0 %, foram obtidas pela testemunha, MC e MM, CC e MF; e os tratamentos que causaram menor percentagem de parasitismo foram IC, IM, PC, CM e CF, respectivamente. Os extratos das diferentes partes do mogno, que apresentaram uma boa percentagem de parasitismo, afetaram o desenvolvimento do parasitoide, com uma baixa emergência de adultos. O PC apresentou um valor baixo de parasitismo e de emergência. Em relação aos ovos tratados quatro dias após o parasitismo, verificou-se que a testemunha apresentou uma boa emergência (98,85%), semelhantes a IM, CF e CC, , respectivamente. O CC foi o extrato mais seletivo e o PC foi o menos seletivo para T. galloi. Action of plants extract on Trichogrammagalloi (Zucchi, 1988)(Hymenoptera: Trichogrammatidae)AbstractThe plants extract may be compatible with other management tactics, especially with biologicalcontrol. so the aim of this work was to evaluate the residual effect of several extracts from cedartree (C) and mahogany tree (M) (bark (C), wood (M) and leaf (F); cecropia tree (I) (bark - C andwood - M) and of the pereiro (P) (bark -C), and its possible effects on the adults of the parasitoidTrichogramma galloi(Zucchi, 1988) (Hymenoptera: Trichogrammatidae). Cards containingparasitised eggs of Diatraea saccharalis(Fabricius, 1794) (Lepidoptera: Crambidae), or containigeggs that would be submitted to the parasitoid were immersed for 30 seconds in the extracts at 5000μg.mL-1. The number of parasitised eggs and adult emergence of the parasitoid were evaluated.The highest rates of parasitism, up to 60.0%, was obtained by the control treatment, MC, MM, CCand MF, and the treatments that caused a lower percentage of parasitism, IC, IM, PC, CM andCF, respectively. The extracts of different parts of mahogany, which showed a good percentageof parasitism, affected the development of the parasitoid with a low adult emergence. The PCshowed a lower parasitism and emergence. In relation to eggs treated four days after parasitism,it was found that the control treatment had a good average in emergency (98.85%), in the samecategory of treatments IM, CF and CC, respectively. The CC extract was more selective and the PCwas the least selective for T. galloi.

The diamondback moth Plutella xylostella is an important pest of cruciferous plants, particularly of cabbage (Brassica oleracea var. acephala). The activity of an ethanolic leaf extract of Annona muricata on the development of the larvae and pupae of a laboratory culture of P. xylostella was evaluated, together with the seasonal variation of this activity. Neonate larvae were fed with kale leaf discs that had been treated by immersion in solutions of A. muricata extracts, and the effects on the duration and viabilities of the larval and pupal phases of the insect were determined. The activities of the extracts varied significantly according to the time of collection of the leaf material and were maximal for leaves collected during the dry period of the year (October-February). At the highest concentration tested (5 mg.ml-1), the most active extract caused 100% larvae mortality; at lower concentrations, the duration of the larval phase was increased by up to 2.6 days and the larvae survival was significantly reduced. The pupal phase was affected far less by exposure to the extracts, although such duration was increased by up to 1 day in the presence of non-lethal concentrations. The significance of these results with respect to the use of extracts of A. muricata for their insecticidal activity is discussed. Plutella xylostella es una importante plaga de las crucíferas, sobre todo de la col (Brassica oleracea var. acephala). Es estudiaron los efectos estacionales del extracto de las hojas de Annona muricata en el desarrollo de las larvas y pupas de P. xylostella provenientes de laboratorio. Las larvas recién eclosionadas se alimentaron con hojas de col tratadas por inmersión con soluciones de los extractos de las hojas. Se determinaron los efectos en la duración y viabilidad del desarrollo de lãs fases de larva y pupa del insecto. La actividad de los extractos varió significativamente según el momento de recolección de las hojas; la máxima actividad se obtuvo en el período seco del año. En la mayor concentración probada (5mg.mL), hubo un 100% de mortandad de las larvas en el extracto más activo: em las concentraciones más bajas, la duración de la fase larvaria, se incrementó hasta 2,6 días y la viabilidad se redujo de forma significativa. La fase de pupa fue menos afectada por la exposición a los extractos aunque su duración se haya incrementado hasta en un día en presencia de concentraciones no letales. Se discute la importancia de estos resultados frente al uso de los extractos de A. muricata como insecticida.