ResumoCom 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 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 (cm 2 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. Key words: Brachiaria, competition, forage plants, crop-cattle integration, Zea mays L. AbstractRecebido para publicação 21/02

Tebuthiuron is often used to control weed growth in sugarcane cultures. This herbicide is highly toxic and can persist in soil for up to 2 years according to its degradation half-life. Hence, its residual effect is highly hazardous for the environment and local habitants via leaching, surface runoff. Screening out of species of green manure as potential phytoremediators for tebuthiuron in soil, with and with no vinasse, accordingly is the scientific point of this study. Green manure species selected for the trial in greenhouse were jack bean [Canavalia ensiformis (L.) DC.], pigeon pea [Cajanus cajan (L. Millsp.)], velvet bean [Mucuna pruriens (L.) DC.)], and millet [Pennisetum glaucum (L.) R.Br.], and Crotalaria juncea L. as bioindicator of this herbicide. The determination/quantification of height, stem diameter, and number of leaves in all plants were monitored, as well as other morphological traits for drafting any inference on biomass production. Moreover, ecotoxicity bioassays were performed from soil samples at the beginning and at the end of the experiment. Results showed preliminary evidence of effective phytoremediation capacity by M. pruriens and P. glaucum in soils with tebuthiuron, as the growth of C. juncea was sustained. Both Gompertz approach and principal component analysis predicted that these green manure species could grow healthier and for longer periods in soils containing tebuthiuron and vinasse and, thus, reduce physiological anomalies due to ecotoxicity. The implications of this study may aid in the implementation of cost-effective strategies targeting decontamination of tebuthiuron in sugarcane crops with vinasse application in fertigation.

The aim of the research was to verify the influence of macro and micronutrients present in the peanut waste (hulls and nuts) for supplementation of Pleurotus ostreatus substrate. The raw materials for base substrate preparation were Brachiaria dictyoneura, sugarcane bagasse (bulk material), rice and wheat bran, calcitic limestone, and gypsum. The following supplement formulations were used as treatments: (1) 100% peanut hulls, (2) 80% peanut hulls + 20% nuts, (3) 60% peanut hulls + 40% nuts, (4) 40% peanut hulls + 60% nuts, (5) 20% peanut hulls + 80% nuts, and (6) 100% nuts. A commercial supplement was also used as an additional treatment. The supplementation was done at spawning using the rates of 1% and 2% wet weight of the substrate. Positive correlations amongst yield and N content, and weight of mushroom and P and K content were verified with 1% supplement. A positive correlation between yield and Cu content, and a negative correlation between yield and Mn content were observed with 2% supplement. The use of peanut waste can be used as supplement for the production of P. ostreatus increasing biological efficiency up to 61%. A better combination can be reached with 20% peanut hulls + 80% nuts or 100% nuts. The addition of 2% supplement in the substrate provided greater yield than 1%.

RESUMO:A eficiência do controle químico da ferrugem-asiática da soja (FAS), além de outros fatores, está associada ao uso da técnica de aplicação de fungicida mais adequada. O trabalho teve por objetivo avaliar tecnologias de aplicação sobre os depósitos da pulverização e controle da FAS nos anos agrícolas de 2009-2010 e 2010-2011. O delineamento experimental foi em blocos casualizados, e os tratamentos distribuídos no esquema fatorial 3x2 (três taxas de aplicação: 60; 110 e 160 L ha -1 com e sem adição de surfactante siliconado) sobre os depósitos da pulverização, usando como marcador o corante Azul Brilhante, em quatro repetições (Experimento 1). Para avaliação da severidade da doença, peso de mil grãos (PMG) e produtividade, foi adotado o mesmo delineamento do primeiro experimento, com acréscimo de uma testemunha (3x2+1), utilizando a mistura fungicida epoxiconazole associado com azoxistrobina, com quatro repetições (Experimento 2). As taxas de aplicação e o uso do surfactante não influenciaram os níveis dos depósitos da pulverização nas folhas das partes mediana e inferior da planta. Pulverização com a mistura fungicida na taxa de 160 L ha -1 proporcionou maior controle da FAS e maior produtividade no ano agrícola de 2010-2011. O controle químico com fungicida, na taxa de aplicação adequada ao estádio de desenvolvimento da planta, torna-se indispensável para a garantia da produtividade na cultura da soja. PALAVRAS-CHAVE: adjuvantes, depósitos da pulverização, tecnologia de aplicação. EFFECTS OF SILICONE SURFACTANT AND APPLICATION RATES ON SPRAY DEPOSITION AND SOYBEAN RUST CONTROLABSTRACT: Chemical control efficiency of Asian soybean rust (ASR), besides other factors, is associated with an appropriate fungicide application technique. This study aimed to evaluate the effect of different application technologies on spray deposition and ASR control in 2009-2010 and 2010-2011 crop seasons. The experimental design was a completely randomized block with four replications in a 3x2 factorial scheme. Three application rates were tested (60, 110 and 160 L ha -1 ) with and without silicone surfactant addition using a Brilliant Blue dye tracer in spray solution to analyze deposition (Experiment 1). For disease severity, thousand grain weight (TGW) and yield were evaluated on the same experimental design as used in Experiment 1 plus a control (3x2+1). It was used the fungicide mixture of azoxystrobin and epoxiconazol in four replications against ASR (Experiment 2). Application rates and surfactant use did not affect spray deposit levels on middle and bottom plant parts. The fungicide mixture at 160 L ha -1 was more effective for disease control and showed a greater yield in the 2010-2011 crop season. Chemical control with fungicides and application rates proper to the plant growing stage become essential to ensure a good soybean yield.

ResumoMuitos são os relatos de ineficiência de agrotóxicos no controle de pragas quando estes são preparados em soluções com água dura e pH elevado. Assim, o trabalho teve como objetivo avaliar o efeito da dureza da água e o pH de soluções acaricidas, em diferentes períodos de tempo após o preparo da calda (0 e 24 horas) no controle do ácaro-da-leprose Brevipalpus phoenicis (Geijskes). O bioensaio foi conduzido sobre frutos de Citrus sinensis (L.) Osbeck cv. Valência. Utilizou-se o delineamento inteiramente ao acaso, com 14 tratamentos e 4 repetições, sendo a parcela experimental composta de um fruto com 10 fêmeas do acarino por fruto. Os acaricidas testados nas dosagens registradas foram: propargite, hexitiazoxi e espirodiclofeno. A pulverização dos frutos foi feita em torre de Potter adaptada, conferindo um volume equivalente a 1616 L ha -1 . As avaliações foram realizadas até 49 dias após aplicação dos produtos, contando o número de adultos, ninfas e, na avaliação final, o número de ovos do acarino por fruto. A dureza da água, pH e tempo de preparo não interferiram no controle do ácaro da leprose. Os acaricidas, após mistura com os diferentes tipos de água, não alteraram o pH das soluções, os quais mostraram pequenas variações de pH no decorrer de 24 horas. Todos os acaricidas propiciaram alta eficácia de controle do acarino nas diferentes condições de preparo de calda, mostrando que esses fatores não interferiram no potencial acaricida.Palavras-chave: Controle químico, qualidade da água de pulverização, ácaro-da-leprose, citros.Effects of water hardness and pH in acaricide spray solutions on the control of Brevipalpus phoenicis on sweet orange fruit AbstractThere are many reports of inefficiency by pesticides in the pest control when they are prepared in solutions with water hardness and high pH. Therefore, the research aimed to evaluate the effects of water hardness, pH and time after preparation (0 and 24h) of acaricides spray solutions on control of the citrus leprosis mite, Brevipalpus phoenicis (Geijskes). The bioassay was carried out on fruit of Citrus sinensis (L.) Osbeck cv. Valência. A completely randomized design with fourteen treatments and four repetitions was used. The sample unit was composed by one fruit with ten mite females. The following acaricides were tested: propargite, hexythiazox and spirodiclofen. The spray on fruit was done by modified Potter tower adjusted to an equivalent volume of 1616 L ha -1 . The evaluations were done until 49 days after the acaricide application by counting the number of adults, nymphs and the number of eggs in the last evaluation. Water hardness, hydrogenionic potential and time after preparation of spray solution did not interfere on leprosis mite control. After the mixture with different water types, the acaricides did not modify the pH of the spray solutions, which showed low variations in pH values over 24 h. All acaricides showed an efficient control of leprosis mite, regardless of the variations in water hardness and pH.