No abstract

The quick, easy, cheap, effective, rugged, and safe (QuEChERS) and the U.S. Food and Drug Administration pesticide multiresidue methods were systematically tested for the analysis of aminocyclopyrachlor, a new synthetic auxin herbicide. Results revealed that these procedures are not suitable, highlighting the need for a publicly available residue method for this new active ingredient. Such a method has been developed and is reported herein for aminocyclopyrachlor residue analysis in vegetation, including white pine, Norway spruce, grass forage, and grass hay. Aminocyclopyrachlor residues were purified from plant tissue extracts by filtration through SPE cartridges with strong anion exchange stationary phases and analyzed using LC/MS/MS. This method was validated at five laboratories across the United States; their results were compared to evaluate reproducibility and ruggedness. The method LOQ was 0.01 mg/kg (ppm) and the LOD 0.003 mg/kg (ppm) for the matrixes tested. A qualitative procedure to confirm the molecular identity of residues based on retention time measurements and ion transition peak area ratios (m/z 214 --> 681m/z 214 --> 101) is also presented.

ResumenEl objetivo de este trabajo fue determinar el momento óptimo de cosecha de los frutos y los parámetros de calidad del aceite de piñón blanco (Jatropha curcas L), adecuados para la producción de biodiesel. El trabajo fue desarrollado en la Parcela Experimental El Porvenir del Instituto Nacional de Innovación Agraria del Perú. Se evaluó las características físicas de los frutos y de las semillas y las características químicas del aceite. Los frutos de piñón utilizados fueron seleccionados al inicio del fructificación. El estado de maduración R2 tuvo una duración de 29 ±1.8 horas, el estado R3 de 12 ± 1.6 horas, el estado R4 27 ± 1.7 horas y finalmente R5 de 24 ± 1.0 horas. El análisis químico mostró que las semillas de piñón contienen en el estado fisiológico R4 un 51.5% de grasa, mientras que el índice de acidez más elevado se encontró en el R6 con 3.01 mgKOH/g aceite. Los frutos de piñón se pueden cosechar en los estados fisiológicos R3, R4 y R5 por contar con elevado contenido de aceite y bajo índice de acidez. Palabras clave: piñón, Jatropha curcas L, estado fisiológico, tiempo de cosecha, biodiesel Determination of Physiological Periods in the Maturation and Quality Oil of Physic nut (Jatropha curcas L.) AbstractThe objective of this work was to determine the optimum time for fruit harvest and the quality parameters of physic nuts (Jatropha curcas L) suitable for the production of biodiesel. This work was developed in the experimental station El Porvenir of Instituto Nacional de Innovación Agraria in Perú. The physical characteristics of the fruits and seeds and the chemical characteristics of the oil were evaluated. The fruits used were selected at the beginning of fruiting. The R2 maturation status lasted 29 ±1.8 hours, the state R3 12 ± 1.6 hours, the state R4 27 ± 1.7 hours and finally R5 24 ± 1.0 hours. Chemical analysis showed that the seeds of physic nuts contain 51.5% fat at the physiological state R4 while the highest acidity was found in the R6 with 1.3 mg KOH/g oil. The fruit of physic nuts can be harvested during the physiological states R3, R4 and R5 to have high oil content and low acidity.

Conduziu-se um experimento na Fazenda Bom Futuro, município de Rondonópolis, MT, em solo Areia Quartzosa, no ano agrícola 1999/2000, visando avaliar os efeitos do herbicida metsulfuron-methyl, aplicado em pós-emergência, no controle de plantas daninhas em campo de produção de sementes de Brachiaria brizantha (braquiária). Os tratamentos foram constituídos de metsulfuron-methyl a 3,0 glha em aplicação única, metsulfuron-methyl a 3,0 glha em duas épocas de aplicação, metsulfuronmethyl a 3,6 glha em aplicação única, metsulfuron-methyl a 3,6 glha em duas épocas de aplicação, 2,4-D a 288 glha (padrão) e testemunha. As plantas daninhas Tridax procumbens, Spermacoce latifolia e Chamaesyce hirta, foram suficientemente controladas através do metsulfuron-methyl a partir da dose de 3,0 glha, em aplicação única. Foram verificados sintomas leves de fitotoxicidade na braquiária, através dos tratamentos com aplicações em duas épocas e com o tratamento padrão 2,4-D. O rendimento de sementes de braquiária e o peso de 100 panículas foram superiores através dos tratamentos químicos, comparados à testemunha. Palavras-chave:Brachiaria brizantha, 2,4-D, Tridax procumbens, Spermacoce latifolia, Chamaesyce hirta. ABSTRACTMetsulfuron-methyl avaliation in the control of weeds in an área ofpasture seed production An experiment was conducted at the Bom Futuro Farm, Rondonópolis, MT during 1999/2000 in a sandy soil, to determine the effects of metsulfuron-methyl on postemergence control of weeds in a field of Brachiaria brizantha seed production. Treatments were: metsulfuron-methyl at 3.0 glha and at 3.6 glha in one application or in two applications, 2,4-D at 288 glha (as a reference) and a check. Tridax procumbens, Spemacoce latifolia, Chamaesyce hirta were controlled by metsulfuron-methyl at 3.0 and 3.6 glha in a sole application. It was observed slight injury-to B. brizantha caused by the treatrnent with two applications of metsulfuron-methyl and by 2,4-D. B. brizantha seed production, weigth of 100 panic\es were ligher in the treatments with herbicides.