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Aqueous extracts of neem, Azadirachta indica A. Juss., leaf and seed cake were tested for toxicity in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) utilizing different methods of application (foliar and systemic). Probit analysis was used to determine the LC50 and regression analysis for mortality at different concentrations of the extracts (0.5%, 1.0%, 1.5%, 2.0% and control treatment). Two caterpillar morphometric variables (larval length and cephalic capsule width) and the scale of damage of attacked plants were measured and, analyzed using the Kruskal-Wallis test (P<0.05). The LC50 values for neem seed cake and leaves were 0.13% and 0.25%, respectively. For larval length and cephalic capsule width, the larvae were more affected to the seed cake extract than leaf extract, however there was no significant difference between the methods of application for these variables. There was no difference in the scale of damage by the extracts and the methods of application analyzed. Both methods of application provided similar results and, the main differences were associated with more efficient of the seed cake extract., Aqueous extracts of neem, Azadirachta indica A. Juss., leaf and seed cake were tested for toxicity in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) utilizing different methods of application (foliar and systemic). Probit analysis was used to determine the LC50 and regression analysis for mortality at different concentrations of the extracts (0.5%, 1.0%, 1.5%, 2.0% and control treatment). Two caterpillar morphometric variables (larval length and cephalic capsule width) and the scale of damage of attacked plants were measured and, analyzed using the Kruskal-Wallis test (H=16.93; P=0.0304). The LC50 values for neem seed cake and leaves were 0.13% and 0.25%, respectively. For larval length and cephalic capsule width, the larvae were more affected to the seed cake extract than leaf extract, however there was no significant difference between the methods of application for these variables. There was no difference in the scale of damage by the extracts and the methods of application analyzed. Both methods of application provided similar results and, the main differences were associated with more efficient of the seed cake extract.

Aqueous extracts of neem, Azadirachta indica A. Juss., leaf and seed cake were tested for toxicity in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) utilizing different methods of application (foliar and systemic). Probit analysis was used to determine the LC50 and regression analysis for mortality at different concentrations of the extracts (0.5%, 1.0%, 1.5%, 2.0% and control treatment). Two caterpillar morphometric variables (larval length and cephalic capsule width) and the scale of damage of attacked plants were measured and, analyzed using the Kruskal-Wallis test (P<0.05). The LC50 values for neem seed cake and leaves were 0.13% and 0.25%, respectively. For larval length and cephalic capsule width, the larvae were more affected to the seed cake extract than leaf extract, however there was no significant difference between the methods of application for these variables. There was no difference in the scale of damage by the extracts and the methods of application analyzed. Both methods of application provided similar results and, the main differences were associated with more efficient of the seed cake extract., Aqueous extracts of neem, Azadirachta indica A. Juss., leaf and seed cake were tested for toxicity in Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) utilizing different methods of application (foliar and systemic). Probit analysis was used to determine the LC50 and regression analysis for mortality at different concentrations of the extracts (0.5%, 1.0%, 1.5%, 2.0% and control treatment). Two caterpillar morphometric variables (larval length and cephalic capsule width) and the scale of damage of attacked plants were measured and, analyzed using the Kruskal-Wallis test (H=16.93; P=0.0304). The LC50 values for neem seed cake and leaves were 0.13% and 0.25%, respectively. For larval length and cephalic capsule width, the larvae were more affected to the seed cake extract than leaf extract, however there was no significant difference between the methods of application for these variables. There was no difference in the scale of damage by the extracts and the methods of application analyzed. Both methods of application provided similar results and, the main differences were associated with more efficient of the seed cake extract.

Objetivou-se avaliar o efeito de extratos aquosos de folhas de nim, Azadirachta indica, frutos de pimenta-malagueta, Capsicum frutescens, rama e folhas de melão-de-são-caetano, Mormodica charantia, sementes de pimenta-do-reino, Piper nigrum e NeenMax® (óleo de nim 2% i.a) para o manejo do pulgão, Lipaphis erysimi, em cultivo orgânico de Brassica oleracea. Aplicações dos extratos a 10% (v/v) foram realizadas semanalmente, durante cinco semanas. Avaliou-se o número de plantas infestadas, porcentagem de folhas infestadas e ocorrência inicial de infestação em diferentes dias após o plantio (DAP). Os tratamentos não causaram redução populacional significativa do pulgão L. erysimi sobre brócoli em sistema orgânico.

Objetivou-se avaliar o efeito de extratos aquosos de folhas de nim, Azadirachta indica, frutos de pimenta-malagueta, Capsicum frutescens, rama e folhas de melão-de-são-caetano, Mormodica charantia, sementes de pimenta-do-reino, Piper nigrum e NeenMax® (óleo de nim 2% i.a) para o manejo do pulgão, Lipaphis erysimi, em cultivo orgânico de Brassica oleracea. Aplicações dos extratos a 10% (v/v) foram realizadas semanalmente, durante cinco semanas. Avaliou-se o número de plantas infestadas, porcentagem de folhas infestadas e ocorrência inicial de infestação em diferentes dias após o plantio (DAP). Os tratamentos não causaram redução populacional significativa do pulgão L. erysimi sobre brócoli em sistema orgânico.

Objetivou-se avaliar o efeito de extratos aquosos de folhas de nim, Azadirachta indica, frutos de pimenta-malagueta, Capsicum frutescens, rama e folhas de melão-de-são-caetano, Mormodica charantia, sementes de pimenta-do-reino, Piper nigrum e NeenMax® (óleo de nim 2% i.a) para o manejo do pulgão, Lipaphis erysimi, em cultivo orgânico de Brassica oleracea. Aplicações dos extratos a 10% (v/v) foram realizadas semanalmente, durante cinco semanas. Avaliou-se o número de plantas infestadas, porcentagem de folhas infestadas e ocorrência inicial de infestação em diferentes dias após o plantio (DAP). Os tratamentos não causaram redução populacional significativa do pulgão L. erysimi sobre brócoli em sistema orgânico.

Objetivou-se avaliar o efeito de extratos aquosos de folhas de nim, Azadirachta indica, frutos de pimenta-malagueta, Capsicum frutescens, rama e folhas de melão-de-são-caetano, Mormodica charantia, sementes de pimenta-do-reino, Piper nigrum e NeenMax® (óleo de nim 2% i.a) para o manejo do pulgão, Lipaphis erysimi, em cultivo orgânico de Brassica oleracea. Aplicações dos extratos a 10% (v/v) foram realizadas semanalmente, durante cinco semanas. Avaliou-se o número de plantas infestadas, porcentagem de folhas infestadas e ocorrência inicial de infestação em diferentes dias após o plantio (DAP). Os tratamentos não causaram redução populacional significativa do pulgão L. erysimi sobre brócoli em sistema orgânico.

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.