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O algodoeiro é atacado por pragas sugadoras que têm sido controladas com inseticidas químicos, causando problemas à saúde do aplicador e poluição do meio ambiente, mas o uso de produtos botânicos como o nim vem sendo estudado nos últimos anos. O efeito do intervalo de aplicação do inseticida Azamax® foi avaliado sobre pragas sugadoras e seus inimigos naturais. O estudo foi conduzido na Embrapa Algodão em Barbalha, Ceará. O Azamax® foi aplicado em dois intervalos de aplicação (sete e 15 dias), em cobertura total das plantas com pulverizador costal manual com bico cônico. As amostragens foram realizadas semanalmente em 40 plantas por parcela dos 13 aos 90 dias após a emergência das plantas. Pulgão, tripes e a cochonilha foram amostrados nos ponteiros das plantas, a mosca branca na folha do 5º nó e o ácaro vermelho na parte mediana, enquanto os inimigos naturais, nos locais onde as pragas foram amostradas. O Azamax® aplicado aos sete e 15 dias reduz a taxa de infestação do pulgão Aphis gossypii, assim como, a mosca branca Bemisia tabaci biótipo B e a cochonilha Planococcus minor, não tendo efeito no ácaro vermelho, para os dois períodos de aplicação. Não foi observado efeito direto do Azamax® sobre a população dos inimigos naturais das principais pragas sugadoras do algodoeiro.

In the northeastern part of Brazil, located 90% within the semi-arid region of the country, we can find areas that present quite peculiar characteristics, amongst these the Caatinga. This biome is characterized by the floristic composition formed of dry forest and in this semi-arid environment there is an increase in the supply of resources during the rainy season. This is a region lacking in research, particularly in the State of Paraíba, where no survey studies of social wasp were carried out yet. Social wasps are an important predator of plagues species. The objective of this study was to conduct a survey of the community of social wasps (Polistinae species) that inhabit in the neotropical dry forest of Paraiba, in the municipalities of Sumé and Prata, and to compare the richness and abundance of wasps located in areas of Caatinga with those inhabiting areas intercropping plantation with organic farming. The present study sampled 10 Polistinae species distributed in six genera. Two new species were registered for the state. The comparison between the community of social wasps of the Caatinga There was not statistical difference in the richness and abundance between the natural vegetation and organic intercropping. This means that agroecosystem attracted community of Polistinae, promoting the maintenance of social wasps in anthropic environmental and favoring the biological control.

This study aimed to evaluate the importance of wild bee and feral honeybee visits for cotton production on conventional and organic farms. Experiments were conducted in Brazil, on a conventional cotton farm in Mato Grosso state in the Amazon biome and on an organic farm in Paraíba state in the Caatinga biome. On the conventional farm, bee assemblage and cotton production were measured near to and far from natural vegetation. Bee richness, fibre fraction, seed number and yield (Kg/ha) were higher by 57.14, 1.95, 17.77 and 18.44% respectively in plots near natural vegetation, but bee abundance did not vary with distance to natural vegetation. On the organic farm, because the cropping area is surrounded by natural vegetation, pollination deficit was evaluated using an exclusion experiment where cotton production of flowers bagged to prevent bee visitation (spontaneous self-pollination) was compared to production of flowers open to bee visitation (open pollination). Open pollinated flowers had higher average boll weight, fibre weight and seed number. Although cotton is not directly dependent on bee pollination, bees increased cotton production on the organic farm by more than 12% for fibre weight and over 17% for seed number. Our data confirm the importance of maintaining communities of pollinators on cotton farms, especially for organic production.

O algodão já foi a principal cultura cultivada no Nordeste, a sua produção alavancou o desenvolvimento de muitas cidades e contribuiu para o desenvolvimento da região semiárida. Ataque de pragas, baixas produtividades, alto custo de produção e baixa nos preços no mercado internacional, aliado a falta de assistência técnica adequada, contribuíram para o declínio da cultura. Objetivou-se com este trabalho avaliar os inseticidas naturais: extrato aquoso da pimenta malagueta, caulim, Azamax®, Rotenat® e Pironat® no manejo agroecológico das principais pragas e seus inimigos naturais do algodoeiro consorciado com as culturas do milho, feijão-caupi e gergelim. Os estudos foram desenvolvidos no campo experimental da Embrapa Algodão em Barbalha, Ceará, onde instalou-se o experimento para avaliação dos produtos naturais, com o delineamento experimental em blocos ao acaso e com quatro repetições, representado por seis tratamentos: T1-Testemunha (sem aplicação), T2-Pimenta malagueta, T3 Caulim, T4-Azamax®, T5- Rotenat® e T6-Pironat®. Os produtos foram aplicados a cada sete dias, seguidos de avaliações também semanais, considerando-se o efeito dos tratamentos sobre a ocorrência dos insetos pragas do algodoeiro e seus inimigos naturais. O Caulim é o produto natural mais eficiente no controle do bicudo do algodoeiro, Anthonomus grandis . A pimenta malagueta não é eficiente no controle das principais pragas do algodoeiro. Os produtos naturais aplicados a cada 7 dias em pulverizações nas folhas do algodoeiro não interferem na presença de inimigos naturais. Cotton was once the main crop grown in the northeast of Brazil; its production boosted the development of many cities and contributed to the development of the semi arid region. Attacks by pests, low productivity, high production costs and low prices on the international market, coupled with a lack of adequate technical assistance, contributed to the decline of the crop. The aim of this study was to evaluate the natural insecticides: aqueous extract from the malagueta pepper, kaolin, Azamax®, Rotenat® and Pironat®, on the agroecological management of the principal pests, with their natural enemies, of cotton intercropped with maize, cowpea and sesame crops. The studies were carried out at the experimental area of Embrapa Algodão, in Barbalha, in the state of Ceará, Brazil (CE), where an experiment was set up to evaluate these natural products, in an experimental design of randomised blocks with four replications, represented by six treatments: T1-Control (no application), T2-Malagueta pepper, T3-Kaolin, T4 Azamax®, T5-Rotenat® and T6- Pironat®. The products were applied every seven days, followed by weekly assessments, considering the effect of the treatments on the occurrence of insect pests of the cotton plant, and on their natural enemies. Kaolin is the most effective natural product in controlling the boll weevil, Anthonomus grandis. Malagueta pepper is not effective in controlling the principle pests of the cotton plant. Natural products applied by spraying the leaves of the cotton plant every 7 days do not interfere with the presence of natural enemies.

The state of Paraíba is included in the semi-arid region of Northeastern Brazil, called Caatinga, and this region is characterized by low and irregular rainfall, with xerophilous vegetation. Social wasps are an important ecological group, which has been utilized for biological control and as bioindicators of environmental quality. Few studies about the diversity of social wasps were accomplished in the Caatinga and there is no survey of social wasps in the state of Paraiba. This study used data collected from city of Sumé, through field research and analysis of previously deposited material from surveys realized by Brazilian Corporation of Agricultural Research (EMBRAPA). Two species of social wasps, Polistes simillimus and Mischocyttarus cearensis, were recorded for the first time in state of Paraiba.

Estudou-se o efeito de inseticidas/acaricidas na mortalidade de ovos e fêmeas adultas do ácaro rajado Tetranychus urticae Koch. Os experimentos foram conduzidos a temperatura de 27 ± 2,0ºC, umidade relativa de 67 ± 6,0% e fotofase de 12h, utilizando-se 50% das dosagens recomendadas para os ingredientes ativos dos produtos Fempropatrina (114 mg/L), Piridabem (94 mg/L), Profenofós (625 mg/L), Bifentrin (45 mg/L) e Dicofol (925 mg/L). Discos de folhas de feijão de porco ( Canavalia ensiformes D.C.), com 3,5 cm de diâmetro cada (contendo 30 ovos), foram imersos nas respectivas caldas e na testemunha (água destilada) durante cinco segundos e secos em temperatura ambiente por 30 minutos. A mortalidade dos ovos foi determinada 96h após a aplicação dos produtos, mediante à quantificação do número de larvas eclodidas. Na avaliação do efeito dos inseticidas/acaricidas sobre adultos, discos de folhas de feijão de porco foram infestados com 15 fêmeas nos intervalos de 0, 24, 48 e 72h após a aplicação. A mortalidade foi avaliada com 24 e 72h após cada infestação. Todos os agrotóxicos proporcionaram 100% de mortalidade de ovos do ácaro rajado, exceto Fempropatrina (eficácia de 89,3%). Nos quatro tempos de infestação, Profenofós, Bifentrin e Dicofol provocaram mortalidade de fêmeas adultas acima de 90%, com 24h de exposição. Piridabem causou mortalidade de 93,3% (tempo 0), 86,7% (24 e 48h) e 63,3% (72h). Fenpropatrina com 24h de exposição apresentou desempenho diferente dos demais produtos, com mortalidade de fêmeas adultas de 68% (tempo 0), 77,3% (24h), 83,9% (48h) e 55% (72h). Com 72h de exposição todos os produtos aumentaram a sua eficácia, com a mortalidade variando de 82,7 a 100%. Concluiu-se que os produtos Profenofós, Bifentrin e Dicofol mostraram-se mais promissores no controle do ácaro rajado. Embora Piridabem e Fempropatrina não tenham apresentado o mesmo desempenho, também podem ser usados de forma criteriosa para evitar o aparecimento de populações resistentes. EFFECTS OF INSETICIDE AND MITECIDE ON EGGS AND ADULTS FEMALES OF TWOSPOTTED SPIDER MITE, Tetranychus urticae KOCH (ACARI: TETRANYCHIDAE) Abstract Inseticide/mitecide effects on eggs and adult females of twospotted spider mite Tetranychies urticae Koch was evaluated. Experiments were carried at 27 ± 2°C under 68 ± 6% relative humidity and 12h photophase. Fenpropathrin (114 mg/L), Pyridaben (94 mg/L), Profenofos (625 mg/L), Bifenthrin (45 mg/L) and Dicofol (925 mg/L) were used at 50% of recommended dose of active ingredient. Canavalia ensiformes D. C. leaf discs, d = 3,5 cm, with 30 eggs each, was dipped in the respective solution and water (control), for 5 seconds, and dried at room temperature for 30 minutes. Eggs mortality was determined 96h after pesticide application, by the number of larvae hatched. In the adults effects, leaf discs were infested with 15 females at 0, 24, 48 and 72h after insecticide/mitecide application. Mortality was evaluated 24 and 72h after each infestation, being considered died those that were immobile after being lightly prodded with a fine soft pointed tip brush. All the agrochemicals caused 100% of mortality on the eggs of the twospotted spider mite, except Fenpropathrin with 89.3%. In the four times of infestation, Profenofos, Bifenthrin and Dicofol, caused upper 90% of mortality, 24h after exposition. Pyridaben caused 93.3% (t = 0), 86.7% (t = 24, 48h), and 63.3% (t = 72h). Fenpropathrin with 24h of exposition showed an abnormal result when compared to the others pesticides, that caused 68% (t = 0), 77.3% (t = 24), 83.9% (t = 48), and 55% (t = 72h) of mortality. All pesticides increased their performance, ranging from 82.7 to 100%, 72h after exposition. It was concluded that the products Profenofos, Bifenthrin and Dicofol showed to be more promising on the control of the twospotted spider mite. Although Pyridaben and Fenpropathrin didn’t show the same performance, they can be also used in a criterious way to avoid the emergence of resistant populations.