RESUMO
A typology of avocado cv. Hass farms was constructed based on information collected from productive units in Antioquia, Colombia. The study aimed to provide key information about the farms for those involved in the design of programs and public policies directed to growers. The data were scrutinized through Multiple Correspondence Analysis (MCA) and Cluster Analysis. The sample was made up of 214 growers of the crop. Quantitative and qualitative variables were employed for the MCA, which rendered 40 dimensions, out of which 16 accounted for 70% of the total inertia (variance) found in the data. These 16 dimensions were used as input for the Cluster Analysis, which provided the following results: 52%, 32% and 15% of the farms were located in Clusters 1, 2 and 3, respectively. The identified farm types can be associated to peasant (Cluster 1) and commercial (Cluster 3) agricultural schemes, plus a transition between them (Cluster 2). The most discriminating variables regarding such categorization were: farm size, farm registry at ICA (Colombian Agricultural Institute), Avocado cv. Hass yield, labor source, presence of crops other than avocado, existence of formal commercial alliances and technical assistance type. The percentage of farmers belonging to grower organizations was high in the three clusters. Growers in Clusters 3 and 2 had established formal commercial alliances which enabled them to access better sale prices for the crop. A trend towards establishing cv. Hass as a monocrop is observed, which may threaten both crop biodiversity and the food security of peasant growers.(AU)
Uma tipologia de fazendas produtoras de abacate cv. Hass foi realizada a partir de informações levantadas em unidades produtivas no departamento de Antioquia, Colômbia. O objetivo do estudo foi fornecer informações importantes sobre as fazendas produtoras da variedade de abacate Hass, com o intuito de apoiar a elaboração de programas e políticas públicas destinados aos produtores desta variedade. Métodos estatísticos multivariados como Análise de Correspondência Múltipla (ACM) e Análise de Clusters foram utilizados. A amostra foi composta por 214 produtores de abacate cv. Hass. Variáveis categóricas de tipo quantitativo e qualitativo foram utilizadas no ACM, o que permitiu a obtenção de 40 dimensões, das quais 16 continham 70% da inércia total (variância) presente nos dados. As 16 dimensões serviram como entrada para a Análise de Clusters, a qual produziu os seguintes resultados: 52%, 32% e 15% das fazendas estiveram localizadas nos Clusters 1, 2 e 3, respectivamente. Os tipos de fazendas identificados podem ser associados a esquemas de agricultura camponesa (Cluster 1), agricultura comercial (Cluster 3), e uma transição entre elas (Cluster 2). Variáveis como a fonte de trabalho, a presença de culturas diferentes ao abacate, a existência de alianças comerciais formais e o tipo de assistência técnica recebida são as mais diferenciadas em relação a esta categorização. A percentagem de produtores pertencentes a organizações de produtores foi alta nos três clusters. Os produtores dos Clusters 3 e 2 estabeleceram alianças formais de negócios, o que lhes permitiu ter acesso a melhores preços de venda da cultura. Há uma tendência a estabelecer o abacate cv. Hass como uma monocultura, o que pode ameaçar tanto a diversidade da agricultura quanto a segurança alimentar dos produtores camponeses.(AU)
Assuntos
Persea/classificação , Fazendas/economia , Fazendas/estatística & dados numéricos , Fazendas/classificaçãoRESUMO
Currently, the reclassification of the genus Persea is under discussion with molecular techniques for DNA analysis representing an alternative for inter- and intra-specific differentiation. In the present study, the traditional random-amplified polymorphic DNA (RAPD) and the inter simple sequence repeat (ISSR) markers were used to determine the genomic relationship of different species and hybrids representative of the subgenera Eriodaphne and Persea in a population conserved in a germplasm bank. The data were analyzed statistically using multivariate methods. In the RAPD analysis, a total of 190 polymorphic bands were produced, with an average of 23.7 bands per primer, the percentage contribution of each primer was from 7.66 to 19.63; the polymorphic information content (PIC) ranged from 0.23 to 0.45, with an average of 0.35. In the ISSR analysis, a total of 111 polymorphic bands were considered, with an average of 18.5 bands per primer, the percentage contribution of each was from 11.83 to 19.57; the PIC ranged from 0.35 to 0.48, with an average of 0.42. The phenograms obtained in each technique showed the relationship among the accessions through the clusters formed. In general, both the techniques grouped representatives of the Persea americana races (P. americana var. drymifolia, P. americana var. guatemalensis, and P. americana var. americana). However, it was not possible to separate the species of Persea used as reference into independent clades. In addition, they tended to separate the representatives of subgenera Eriodaphne and Persea.
Assuntos
Persea/genética , Filogenia , Polimorfismo Genético , Marcadores Genéticos , Repetições de Microssatélites , Persea/classificaçãoRESUMO
Objetivo: Determinar si la administración por vía oral del extracto etanólico de la semilla de Persea americana (palta) en ratones hembras tiene efecto anticonceptivo. Diseño: Estudio experimental. Lugar: Bioterio de la Facultad de Medicina y Facultad de Farmacia y Bioquímica, Universidad Nacional Mayor de San Marcos. Material biológico: Ratones cepa BALB/c-53. Intervenciones: Cuarenta ratones hembras fueron divididos aleatoriamente en 4 grandes grupos, de 10 cada uno. El primero fue control, con Solución de Goma de Tragacanto (GT) 1 por ciento 10mL/kg y los grupos restantes con extracto vía oral a dosis de 25mg/kg, 50mg/kg y 100mg/kg, durante 16 días. Cada grupo consideró 10 hembras y 2 machos juntos, que fueron divididos en 2 sub-grupos de 5 hembras y 1 macho por cada jaula. Al día 17 las ratones hembras fueron sacrificadas, para observar la presencia de fetos en el útero. Así mismo se realizó el estudio fotoquímico y la cromatografía del extracto etanólico de la semilla de Persea americana; y la dosis letal media. Principales medidas de resultados: El efecto anticonceptivo se evaluó mediante la cuantificación del indicador macroscópico preñez. Análisis estadístico: El análisis estadístico fue realizado empleando el software SPSS versión 20.0 y Excel office 2010. Se realizaron análisis descriptivos y pruebas estadísticas de significancia. Resultados: Los saponinas y alcaloides estuvieron en mayor cantidad en el extracto etanólico, pero también hubo presencia de flavonoides y taninos. Se mostró un efecto anticonceptivo con porcentajes de 30 por ciento, 20 por ciento y 0 por ciento a dosis de 25, 50 y 100mg/Kg de peso, respectivamente. Los controles mostraron un 10 por ciento de ausencia de preñez. Cabe señalar que el 100 por ciento de las ratones hembras que recibieron el extracto etanólico de la planta a máxima dosis resultó grávida y que la evolución de la gestación estuvo altamente avanzada en comparación del grupo control. Conclusiones: En condiciones...
Objective: To determine whether oral administration of ethanolic seed extract of Persea americana (avocado) in female mice has contraceptive effect. Design: Experimental study. Location: Bioterio's Faculty of Medicine and Faculty of Pharmacy and Biochemistry, Universidad Nacional Mayor de San Marcos. Biological material: Mice BALB/c-53 strain. Interventions: Forty female mice were randomly divided into 4 main groups of 10 each. The first control group received Gum Tragacanth (GT) Solution 1 per cent 10mL/kg and the others groups received orally extract at doses of 25mg/kg, 5mg/kg and 100mg/kg, for 16 days. Each group considered 10 females and 2 males together; they were divided into 2 sub-groups of 5 females and 1 male per cage. At day 17 the female mice were sacrificed, to observe the presence of fetuses in the uterus. Also the study photochemical and chromatography of the ethanol extract of Persea americana seed was performed. Main outcome measures: The contraceptive effect was assessed by quantifying the macroscopic indicator pregnancy. Statistical analysis: Statistical analysis was performed using the SPSS software version 20.0 and Excel office 2010. Descriptive analyzes and statistical tests of significance were performed. Results: The saponins and alkaloids were in greater amounts in the ethanol extract, but flavonoids and tannins were presents too. Contraceptive effect with percentage of 30 per cent, 20 per cent and 0 per cent at doses of 25, 50 and 100mg/kg per corporal weight, respectively showed. Controls showed 10 per cent of absence of pregnancy. It should be noted that 100 per cent of the female mice receiving the ethanolic extract of the plant to maximum dose was pregnant and the course of pregnancy was highly advanced compared the control group. Conclusions: In experimental conditions, the ethanol extract of seed of Persea americana (avocado) showed a poor contraceptive effect with the lowest dose that was not statistically significant; and...
Assuntos
Feminino , Animais , Camundongos , Anticoncepção , Experimentação Animal , Extratos Vegetais , Persea/classificação , SementesRESUMO
The objective of this study was to determine the host status in Mexico of commercially cultivated and marketed avocado, Persea americana (Mill.), 'Hass' to Anastrepha ludens (Loew), Anastrepha obliqua (Macquart), Anastrepha serpentina (Wiedemann), and Anastrepha striata (Schiner) (Diptera: Tephritidae). Experiments in Michoacán, Mexico, were carried out in six orchards located at three altitudes above sea level during two times (August-October 2001 and April-June 2002). They included choice ('Hass' avocado plus natural host) and no-choice foraging behavior tests on trees under field cages; no-choice, forced infestation trials on caged, fruit-bearing branches in the field, and with individual fruit under laboratory conditions; infestation trials using 'Hass' avocados left unprotected over 1 and 7 d on the ground of orchards; studies to ascertain depth of oviposition and determine egg hatchability; and experiments to determine susceptibility by using time elapsed since removal of fruit from tree as the experimental variable. We trapped adult Anastrepha (n = 7,936) in all orchards and dissected fruit (n = 7,695) from orchards and packing houses (n = 1,620) in search of eggs or larvae. Most (96.7%) A. ludens, A. obliqua, A. striata, and A. serpentina adults were captured in low-elevation orchards. No eggs or larvae were detected in any of the fruit from foraging behavior studies or dissected fruit from orchards or packing houses. Of 5,200 mature, intact fruit on trees in the field forcibly exposed to no-choice female oviposition activity (five females/fruit), we only found four fruit infested by A. ludens but no adults emerged. 'Hass' avocados only became marginally susceptible to attack by A. ludens (but not A. obliqua, A. serpentina, and A. striata) 24 h after being removed from the tree. Fruit placed on the ground in orchards (n = 3,600) were occasionally infested by Neosilba batesi (Curran) (Diptera: Lonchaeidae), a decomposer, but not Anastrepha spp. Based on our results, commercially cultivated and marketed P. americana 'Hass' should not be considered a natural host of A. ludens, A. obliqua, A. striata, and A. serpentina in Mexico.