Distribuição vertical de Crysodeixis includens (Lepidoptera: Noctuidae) em cultivar transgênica e convencional de algodoeiro / Vertical distribution of Crysodeixis includens (Lepidoptera: Noctuidae) in transgenic and conventional cotton cultivars

O objetivo deste estudo foi avaliar a distribuição intra-planta de lagartas de Crysodeixis includens no cultivar convencional FM 993 e na sua isolinha transgênica FM 975 WS (WideStrike), que expressa as proteínas tóxicas Cry1Ac e Cry1F. O experimento foi realizado com o delineamento em blocos casualizados em esquema de parcelas subdivididas, com seis tratamentos (três terços da planta x duas faces foliares) e 40 repetições. As plantas foram visualmente divididas em três terços (superior, médio e inferior) e nas faces adaxial e abaxial das folhas, registrando-se o número de lagartas. Lagartas de C. includens foram identificadas em maior número no cultivar não-Bt (FM 993), enquanto que, na cultivar transgênica FM 975 WS (WideStrike), foram constatadas apenas as pequenas, em número significativamente menor que na sua isolinha não-Bt (FM 993). As lagartas, independentemente do tamanho e do cultivar, foram mais encontradas na parte inferior e mediana do dossel das plantas e, ainda, na face abaxial das folhas.

The aim of this study was to evaluate the intra-plant distribution of Crysodeixis includens in conventional FM 993 and transgenic FM 975 WS (WideStrike), which express the toxic proteins Cry1Ac and Cry1F. The experiment was carried out in a split-plot design arranged under a complete block design with six treatments (three thirds x two plant leaf surface) and 40 repetitions. The plants were visually divided into three thirds (upper, middle and lower) and into adaxial and abaxial leaves, registering the number of caterpillars. C includens caterpillars were found at higher numbers in the non-Bt cultivar (FM 993), while in the transgenic cultivar FM 975 WS (WideStrike) were found only small caterpillars, and significantly fewer compared to their non-Bt isoline (FM 993). Caterpillars, regardless of size and cultivar, were most commonly found at the bottom and middle thirds of the plant canopy and on the abaxial leaf surface.

Distribuição vertical de Crysodeixis includens (Lepidoptera: Noctuidae) em cultivar transgênica e convencional de algodoeiro / Vertical distribution of Crysodeixis includens (Lepidoptera: Noctuidae) in transgenic and conventional cotton cultivars

O objetivo deste estudo foi avaliar a distribuição intra-planta de lagartas de Crysodeixis includens no cultivar convencional FM 993 e na sua isolinha transgênica FM 975 WS (WideStrike), que expressa as proteínas tóxicas Cry1Ac e Cry1F. O experimento foi realizado com o delineamento em blocos casualizados em esquema de parcelas subdivididas, com seis tratamentos (três terços da planta x duas faces foliares) e 40 repetições. As plantas foram visualmente divididas em três terços (superior, médio e inferior) e nas faces adaxial e abaxial das folhas, registrando-se o número de lagartas. Lagartas de C. includens foram identificadas em maior número no cultivar não-Bt (FM 993), enquanto que, na cultivar transgênica FM 975 WS (WideStrike), foram constatadas apenas as pequenas, em número significativamente menor que na sua isolinha não-Bt (FM 993). As lagartas, independentemente do tamanho e do cultivar, foram mais encontradas na parte inferior e mediana do dossel das plantas e, ainda, na face abaxial das folhas.(AU)

The aim of this study was to evaluate the intra-plant distribution of Crysodeixis includens in conventional FM 993 and transgenic FM 975 WS (WideStrike), which express the toxic proteins Cry1Ac and Cry1F. The experiment was carried out in a split-plot design arranged under a complete block design with six treatments (three thirds x two plant leaf surface) and 40 repetitions. The plants were visually divided into three thirds (upper, middle and lower) and into adaxial and abaxial leaves, registering the number of caterpillars. C includens caterpillars were found at higher numbers in the non-Bt cultivar (FM 993), while in the transgenic cultivar FM 975 WS (WideStrike) were found only small caterpillars, and significantly fewer compared to their non-Bt isoline (FM 993). Caterpillars, regardless of size and cultivar, were most commonly found at the bottom and middle thirds of the plant canopy and on the abaxial leaf surface.(AU)

Otimização da atividade de herbicidas com diferentes adjuvantes na fitotoxicidade de Digitaria insularis no estádio de florescimento / Optimizing activity of herbicides with different adjuvant on phytotoxicityof Digitaria insularis at flowering stage

O presente trabalho teve como objetivo quantificar o efeito proporcionado pela interação entre os herbicidas clethodim e paraquat associados com diferentes classes de adjuvantes na fitotoxicidade de Digitaria insularis no estádio de florescimento. Os herbicidas foram aplicados nas doses de 0; 6,25; 12,5; 25; 50; 75 e 100% da recomendada pelo fabricante, de forma isolada e em mistura com os adjuvantes: nonil fenoxi poli (etilenoxi) etanol (0,05%); copolímero de poliéter e silicone (0,1%); lecitina e ácido propiônico (0,5%) e óleo mineral (0,5%) no delineamento inteiramente casualizado com cinco repetições em esquema fatorial (doses dos herbicidas x adjuvantes). O efeito fitotóxico foi visualmente avaliado aos 12 dias após aplicação (DAA) para o herbicida paraquat e aos 21 DAA para o herbicida clethodim. Verificou-se em plantas de D. insularis fitotoxidade potencializada para o herbicida clethodim nos tratamentos com os adjuvantes nonil fenoxi poli (etilenoxi) etanol, lecitina e ácido propiônico e óleo mineral .Para o herbicida paraquat, a potencialização da fitotoxicidade nas plantas de D. insularis foi proporcionada somente pelo tratamento com o adjuvante lecitina e ácido propiônico.(AU)

The aim of this paper was quantify the effect of the herbicides clethodim and paraquat associated with different adjuvants class on phytotoxicity of Digitaria insularis at flowering stage. The herbicides were applied at 0, 6.25, 12.5, 25, 50, 75 and 100% of recommended label isolated or associated with the adjuvants: nonylphenoxy polyethoxy ethanol at 0.05%; silicone polyether copolymer at 0.1%; lecithin-based adjuvant and acid propionic at 0.5% and mineral oil at 0.5%. The experimental design was completely randomized with five replications in factorial scheme (herbicides rates x adjuvants). The phytotoxicity effect was visually assessed for paraquat at 12 days after treatment (DAT) and at 21 DAT for clethodim. The treatments applied clethodim with the adjuvants nonylphenoxy polyethoxy ethanol, lecithin-based adjuvant and acid propionic and mineral oil significantly increased the phytotoxicity of D. insularis plants. For the paraquat the increase phytotoxicity of D. insularis plants was provided by the treatment with the lecithin-based and acid propionic adjuvant.(AU)

Otimização da atividade de herbicidas com diferentes adjuvantes na fitotoxicidade de Digitaria insularis no estádio de florescimento / Optimizing activity of herbicides with different adjuvant on phytotoxicityof Digitaria insularis at flowering stage

O presente trabalho teve como objetivo quantificar o efeito proporcionado pela interação entre os herbicidas clethodim e paraquat associados com diferentes classes de adjuvantes na fitotoxicidade de Digitaria insularis no estádio de florescimento. Os herbicidas foram aplicados nas doses de 0; 6,25; 12,5; 25; 50; 75 e 100% da recomendada pelo fabricante, de forma isolada e em mistura com os adjuvantes: nonil fenoxi poli (etilenoxi) etanol (0,05%); copolímero de poliéter e silicone (0,1%); lecitina e ácido propiônico (0,5%) e óleo mineral (0,5%) no delineamento inteiramente casualizado com cinco repetições em esquema fatorial (doses dos herbicidas x adjuvantes). O efeito fitotóxico foi visualmente avaliado aos 12 dias após aplicação (DAA) para o herbicida paraquat e aos 21 DAA para o herbicida clethodim. Verificou-se em plantas de D. insularis fitotoxidade potencializada para o herbicida clethodim nos tratamentos com os adjuvantes nonil fenoxi poli (etilenoxi) etanol, lecitina e ácido propiônico e óleo mineral .Para o herbicida paraquat, a potencialização da fitotoxicidade nas plantas de D. insularis foi proporcionada somente pelo tratamento com o adjuvante lecitina e ácido propiônico.

The aim of this paper was quantify the effect of the herbicides clethodim and paraquat associated with different adjuvants class on phytotoxicity of Digitaria insularis at flowering stage. The herbicides were applied at 0, 6.25, 12.5, 25, 50, 75 and 100% of recommended label isolated or associated with the adjuvants: nonylphenoxy polyethoxy ethanol at 0.05%; silicone polyether copolymer at 0.1%; lecithin-based adjuvant and acid propionic at 0.5% and mineral oil at 0.5%. The experimental design was completely randomized with five replications in factorial scheme (herbicides rates x adjuvants). The phytotoxicity effect was visually assessed for paraquat at 12 days after treatment (DAT) and at 21 DAT for clethodim. The treatments applied clethodim with the adjuvants nonylphenoxy polyethoxy ethanol, lecithin-based adjuvant and acid propionic and mineral oil significantly increased the phytotoxicity of D. insularis plants. For the paraquat the increase phytotoxicity of D. insularis plants was provided by the treatment with the lecithin-based and acid propionic adjuvant.

Optimization of spray deposition and Tetranychus urticae control with air assisted and electrostatic sprayer

Improved spray deposition can be attained by electrostatically charging spray droplets, which increases the attraction of droplets to plants and decreases operator exposure to pesticide and losses to the environment. However, this technique alone is not sufficient to achieve desirable penetration of the spray solution into the crop canopy; thus, air assistance can be added to the electrostatic spraying to further improve spray deposition. This study was conducted to compare different spraying technologies on spray deposition and two-spotted spider mite control in cut chrysanthemum. Treatments included in the study were: conventional TJ 8003 double flat fan nozzles, conventional TXVK-3 hollow cone nozzles, semi-stationary motorized jet launched spray with electrostatic spray system (ESS) and air assistance (AA), and semi-stationary motorized jet launched spray with AA only (no ESS). To evaluate the effect of these spraying technologies on the control of two-spotted spider mite, a control treatment was included that did not receive an acaricide application. The AA spraying technology, with or without ESS, optimized spray deposition and provided satisfactory two-spotted spider mite control up to 4 days after application.

Optimization of spray deposition and Tetranychus urticae control with air assisted and electrostatic sprayer

Improved spray deposition can be attained by electrostatically charging spray droplets, which increases the attraction of droplets to plants and decreases operator exposure to pesticide and losses to the environment. However, this technique alone is not sufficient to achieve desirable penetration of the spray solution into the crop canopy; thus, air assistance can be added to the electrostatic spraying to further improve spray deposition. This study was conducted to compare different spraying technologies on spray deposition and two-spotted spider mite control in cut chrysanthemum. Treatments included in the study were: conventional TJ 8003 double flat fan nozzles, conventional TXVK-3 hollow cone nozzles, semi-stationary motorized jet launched spray with electrostatic spray system (ESS) and air assistance (AA), and semi-stationary motorized jet launched spray with AA only (no ESS). To evaluate the effect of these spraying technologies on the control of two-spotted spider mite, a control treatment was included that did not receive an acaricide application. The AA spraying technology, with or without ESS, optimized spray deposition and provided satisfactory two-spotted spider mite control up to 4 days after application.(AU)

Interference of spray volume, fruit growth and rainfall on spray deposits in citrus black spot control periods / Interferência do volume de calda, crescimento dos frutos e precipitação pluviométrica sobre os depósitos da pulverização no período de controle da mancha preta dos citros

Citrus black spot (CBS) caused by Guignardia citricarpa is one of the most serious Brazilian citrus diseases. This study aims to assess the interference of three application volumes in spray deposition citrus fruit, as well as fruit growth and rainfall effects on spray deposit reduction during the CBS control period. The experiment was carried out in a commercial citrus orchard, with sixteen-year-old trees of the Valencia variety, in Mogi Guaçu, São Paulo State, Brazil. The spray volumes were: 3.5 (1333L ha-1), 4.5 (1714L ha-1) and 8.5 (3238L ha-1) litres per tree, sprayed by an airblast sprayer using fungicides at recommended periods for disease control. The spray deposition quantification and residue was done by spectrophotometry using a copper oxychloride tracer. Samples were collected in three height zones of the tree (top, middle and bottom) and placed between trees on line plantation. Spray depositions were significantly smaller in the first application as a consequence of reduced fruit size. The spray losses on average for each day of rainfall ranged from 4.0 to 5.7%. There was no significant difference between application volumes regarding spray deposition on citrus fruit,which makes possible the reduction of application volumes, however, it is necessary to improve spraying techniques for the top zone of the citrus tree.(AU)

A pinta preta ou mancha preta em citros (MPC) está entre as mais importantes doenças da citricultura brasileira. O trabalho teve como objetivo avaliar a interferência de três volumes de pulverização na deposição da calda em frutos cítricos e o efeito do crescimento dos frutos e da precipitação pluviométrica na redução dos depósitos, durante o período de controle da doença. O experimento foi conduzido em pomar comercial com 16 anos, da variedade Valencia, na região de Mogi Guaçu, SP. Os tratamentos consistiram dos volumes de 3,5 (1333L ha-1); 4,5 (1714L ha-1) e 8,5 (3238L ha-1) L planta-1, aplicados por um pulverizador de arrasto com jato transportado, utilizando fungicidas nos períodos recomendados para controle da doença. A quantificação dos depósitos/resíduos foi por espectrofotometria, usando oxicloreto de cobre como traçador. Os frutos foram coletados em três alturas da planta, na região entre plantas da linha de plantio. Os depósitos foram significativamente inferiores na primeira aplicação, como consequência do tamanho reduzido do fruto. As perdas dos depósitos médios de calda, por dia de chuva, variaram de 4,0 a 5,7%. Não ocorreram diferenças significativas entre volumes de aplicação quanto à deposição sobre os frutos, possibilitando a redução de volumes, contudo, torna-se necessário melhorar as técnicas de aplicação na parte superior da planta.(AU)

Interferência de Brachiaria Ruziziensis sobre plantas daninhas em sistema de consórcio com milho / Interference of Brachiaria Ruziziensis on the weeds in intercropping with corn crop

Com relação às forrageiras tropicais, a espécie Brachiaria ruziziensis destaca-se pela grande aceitabilidade pelos bovinos quando comparada às demais espécies do gênero Brachiaria, além de excelente habilidade para competir com plantas daninhas. Com isso, o estudo objetivou avaliar os efeitos de densidades de Brachiaria ruziziensis no consórcio com a cultura do milho, em relação ao controle e desenvolvimento de plantas daninhas no sistema de integração lavoura-pecuária. O experimento foi realizado durante o período de dezembro/2007 a maio/2008, em área experimental pertencente à Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba ­ SP. Os tratamentos foram constituídos, em arranjo fatorial, pela combinação de quatro densidades de Brachiaria ruziziensis (0, 10, 15 e 20 kg ha-1) e três espécies de plantas daninhas (Ipomoea grandifolia, Digitaria horizontalis e Cenchrus echinatus), em cultivo consorciado com milho. As avaliações realizadas foram: a infestação das espécies daninhas (densidade de plantas m-2), a fitomassa seca (g planta-1) e a área foliar (cm2 planta-1). Constatou-se que Brachiaria ruziziensis reduziu a infestação de todas as plantas daninhas avaliadas. Verificou-se, ainda, que as espécies Digitaria horizontalis e Ipomoea grandifolia foram as plantas daninhas de mais difícil controle.

Regarding tropical forage plants, the specie Brachiaria ruziziensis are prominence for to be most acceptable for cattle when compared with others Brachiaria species, besides the excellent competitive ability with weeds. Then, this study aimed to evaluate the effects of Brachiaria ruziziensis density in intercropping with corn crop, about weeds control and weeds development in the crop-cattle integration system. The experiment was realized during the period between December/2007 to May/2008, in the experimental area of Escola Superior de Agricultura "Luiz de Queiroz", Piracicaba ­ SP. The treatment was composed in a factorial arrangement, by combination of four Brachiaria ruziziensis density (0, 10, 15 and 20 kg ha-1) and three weed species ((Ipomoea grandifolia, Digitaria horizontalis e Cenchrus echinatus), in intercropping with corn crop. The evaluations realized were: weed infestation (density m-2), the dry biomass (g plant-1) and leaf area (cm2 plant-1). It was noted that Brachiaria ruziziensis reduced the all of weeds infestation evaluated. Also, it was checked that Digitaria horizontalis and Ipomoea grandifolia were the weeds with most difficult control.