Chromosomic studies in Zephyranthes citrina baker (Amaryllidaceae), a polyploid ornamental / Estudios cromosómicos en Zephyranthes citrina baker (Amaryllidaceae), un poliploide ornamental

ABSTRACT Zephyranthes citrina is an ornamental American bulbous plant used as an ornamental garden crop for the aesthetic qualities of its yellow perigonium. The objective of this work was to characterize the species by classical chromosome staining and fluorochrome banding. A sporophytic chromosome number of 2n=8x=48 chromosomes was observed, being the karyotypic formula 20 m + 26 sm + 2 st. Satellites were detected in the short arm of metacentric chromosomes 8, 9, 11 and 12, which colocalized with constitutive heterochromatin CMA+/DAPI-/0 bands. The karyotype comprised chromosome pairs with terminal constitutive heterochromatin bands that included satellites and heteromorphic clusters indicating that it is an allooctoploid. These results will be used as a tool for monitoring genetic improvement, in interspecific crosses and its progenies and in biotechnological procedures by in vitro culture.

RESUMEN Zephyranhtes citrina es una planta bulbosa americana, ornamental, utilizada en jardines por las cualidades estéticas de su perigonio amarillo. El objetivo de este trabajo fue caracterizar citogenéticamente la especie con tinción clásica convencional y bandeo cromosómico. Se observó un número cromosómico esporofítico de 2n=8x=48, siendo la fórmula cariotípica 20 m + 26 sm + 2st. Se detectaron satélites en el brazo corto de los cromosomas metacéntricos 8, 9, 11 y 12, que co-localizaron con bandas de heterocromatina constitutiva CMA+/DAPI-. El cariotipo comprendió pares de cromosomas con bandas de heterocromatina constitutivas terminales que incluyeron satélites y grupos heteromórficos que indican que es un alooctoploide. Estos resultados serán usados como herramientas en el monitoreo del mejoramiento genético, en análisis de cruzamientos interespecíficos y progenies y en procedimientos biotecnológicos de cultivo in vitro.

La diversidad genética y la variabilidad genética: dos conceptos diferentes asociados al germoplasma y al mejoramiento genético vegetal / Genetic diversity and genetic variability: two different concepts associated to plant germplasm and breeding

En este trabajo se diferencian a los recursos fitogenéticos in situ y ex situ para protección y conservación, de aquellos recursos que colecciona, mantiene y utiliza el hombre para su subsistencia desarrollando variedades cultivadas obtenidas por cualquier método de selección artificial. La imprecisión, confusión y distorsión encontradas en muchos trabajos relacionados al tema aquí planteado, con respecto a la terminología, su significado, sus alcances y sus consecuencias, motivaron el desarrollo de este trabajo de opinión. En mejoramiento, las colecciones de trabajo son utilizadas como una fuente de variabilidad y adaptación. En ese proceso de obtención de cultivares, indefectiblemente, se utiliza sólo una parte de la variabilidad genética del inicio, que se restringe en cada ciclo selectivo. La confusión mencionada con respecto a la pérdida de variabilidad genética se debe a que las mayores probabilidades de éxito en un programa de mejoramiento estarán asociadas a la disponibilidad de una amplia variabilidad genética en la colección de trabajo base del mejoramiento y no en el cultivar obtenido. La diversidad genética se conserva y protege en otro ámbito y con otras disciplinas. La variabilidad genética se re-utiliza y elimina selectivamente para obtener nuevos cultivares en los procesos de selección artificial. El hombre, al obtener variedades primitivas o nuevos cultivares modernos, siempre perdió variabilidad genética con respecto a la población que le dio origen, como consecuencia del mismo proceso selectivo. Ante ese contexto, respetando la biodiversidad, se puede mantener la productividad agrícola a largo plazo con el aporte concreto del mejoramiento genético.

This paper differentiates plant genetic resources maintained in situ and ex situ for protection and conservation, from those resources that man collects, maintains and uses for his subsistence by developing cultivated varieties through any artificial selection method. The imprecision, confusion and distortion found in many papers related to the issue raised here with respect to terminology, its meaning, its scope and its consequences, motivated the development of this opinion work. In plant breeding working collections are used as a source of variability and adaptation. In this process, unfailingly, only a part of the genetic variability is used, which is restricted in each selective cycle since the purpose of this process is to obtain new cultivars. In the selection process there is always a loss of genetic variability with respect to the population that gave rise to it. The confusion mentioned with respect to the loss of genetic variability resides in the following: the greater probabilities of success in a plant breeding program will be associated to the availability of a wide genetic variability in the starting elite collection and not in the obtained cultivar. One of the reiterated concepts attributes the loss of genetic variability to the advent of new cultivars and the narrow genetic base that they represent. The loss of genetic variability is a consequence of the achievement of genetic progress in plant breeding. In this context, the respect for diversity in protected areas and agrobiodiversity in agricultural areas, is the way for producing profitable yields while maintaining the long-term productivity as a result of the implementation of plant breeding.

Teor e composição do óleo essencial de quatro acessos e duas cultivares de manjericão (Ocimum basilicum L. ) / Essential oil composition and content of different accessions and cultivars of basil (Ocimum basilicum L. )

O objetivo desse estudo foi avaliar o teor e a composição química dos óleos essenciais de quatro acessos silvestres de manjericão (Ocimum basilicum L.), provenientes de diferentes regiões geográficas, e duas cultivares comerciais cultivados sob as mesmas condições edafoclimáticas. As sementes dos acessos foram coletadas nos município de Gurupi-TO (GUR) e de Monte Alegre-GO (MAL, MVE e FPS) e as sementes da cultivar comercial manjericão roxo (MR) foram adquiridas no comércio de Gurupi e da cultivar Maria Bonita (MB) foram fornecidas pelo Horto de Plantas Medicinais da Universidade Federal de Lavras. O plantio foi realizado em vasos com capacidade de dez litros utilizando-se como substrato: solo de barranco e esterco bovino na proporção 2:1. O óleo essencial foi obtido por hidrodestilação em aparelho tipo Clevenger e a identificação e a porcentagem relativa dos compostos do óleo essencial foi realizada por Cromatografia à Gás acoplada a Detector de Espectrometria de Massas. Foram identificados trinta e nove substâncias nos óleos essenciais obtidos, abrangendo monoterpenos, sesquiterpenos e fenilpropanoides. Nas cultivares MB e MR o composto majoritário foi o linalol, enquanto nos acessos silvestres (MAL, GUR, FPS e MVE) o composto em maior quantidade foi o (E)-cinamato de metila. O maior teor de óleo essencial foi obtido na cultivar Maria Bonita (3,77%).

The objective of this study was to evaluate the essential oil chemical composition and content of four wild accessions of basil (Ocimum basilicum L.), from different geographical regions, and two commercial cultivars grown under the same edaphoclimatic conditions. The seeds of the accessions were collected in the municipality of Gurupi, state of Tocantins (GUR), and Monte Alegre, state ofGoiás (MAL, MVE and FPS), and the seeds of the commercial cultivar of purple basil (MR) were acquired in the Gurupi market and the seeds of the commercial cultivar Maria Bonita (MB) were provided by the Garden of Medicinal Plants of the Federal University of Lavras. The seeds were planted in pots with a capacity of ten liters using as substrate soil from earth works and cattle manure in the proportion of 2:1. The essential oil was obtained by hydrodistillation using a Clevenger-type apparatus, and the identification and the relative percentage of the compounds of the essential oil were performed by Gas Chromatography coupled to Mass Spectrometry Detector. Thirty-nine compounds were identified in the essential oils obtained, which were divided into monoterpenes, sesquiterpenes and phenylpropanoids. In the cultivars MB and MR, the major compound was linalool, and in the wild accessions (MAL, GUR, FPS and MVE) it was the (E)-methyl cinnamate. The highest content of essential oil was obtained from the cultivar Maria Bonita (3.77%).

Intellectual Property Right of Transgenic Crops and Right to Work: Bioethical Challenges in Rural Communities.

Abstract: Increasing importance of intellectual property rights (IPR) over the area of seed production, is radically transforming agricultural production relations. One major effect of this transformation is the exclusive control of biotech companies on process of transaction of GM crops. This new status, that is the part of a trend that was set in national and international documents to protect inventors, may have adverse impact on the right to work of poor and vulnerable farmers in developing countries. In the framework of international human rights, the right to work is the fundamental right of every one to have sustainable access to decent work that meets the needs and welfare of his livelihood. Rural communities enjoy this right similar to the urban communities. But, the main question, which is our major concern, is the relationship between IPR and the right to work with attention to articles of International Covenant on Economic, Social and Cultural right and International Treaty on Plant Genetic Resources for Food and Agriculture.

Diversidad y dittribución de las passifloraceae en el departamento del huila en Colombia / Diversity and Distribution of Passifloraceae in the Department of Huila in Colombia

Colombia es el país con mayor diversidad de Passifloraceae con 170 especies reportadas, tanto en formas silvestres como cultivadas. Sin embargo, existen zonas en el país donde esta riqueza ha sido poco explorada, como el departamento del Huila en el suroriente de la zona andina. Por esta razón, se revisaron las listas de inventarios con el objetivo de actualizar y establecer la distribución espacial de las especies en esta región con base en registros de herbario, literatura y datos de campo, para proponer estrategias de conservación. Un total de 26 especies pertenecientes al género Passiflora L. son registradas en el Huila entre los 1500 y 2500 msnm. Ocho de las especies son cultivadas y las otras 18 silvestres, se localizan principalmente en bordes de caminos y bosques secundarios. El bajo número de registros y de especies presentes en este departamento es el reflejo de la carencia de iniciativas de investigación sobre la biodiversidad florística. Lo anterior sugiere que esta región puede ser el escenario de muchas especies desconocidas en zonas poco o no exploradas. Por esta razón, la conservación in situ y de sus hábitats es una tarea urgente, al igual que la caracterización y evaluación de los recursos genéticos, lo que permitirá conocer los atributos de las especies silvestres y cultivadas para un mejor uso de la biodiversidad.

Colombia is the country with the greatest Passifloraceae diversity with 170 reported species of both wild and cultivated forms. However, there are areas in the country where this wealth has slightly been explored such as the department of Huila in the South East of the Andes. For this reason, inventory lists were reviewed in order to update and establish the spatial distribution of the species in this region based on herbarium records, literature and field data, and propose conservation strategies. A total of 26 species belonging to the genus Passiflora L. are recorded in Huila between 1500 and 2500 masl. Eight species are cultivated and the others 18 that are wild are found mainly along roadsides and in secondary forests. The low number of species records in this department reflects the lack of research initiatives on floristic biodiversity. This suggests that this region may harbor many unknown species in little or unexplored areas. For this reason, conservation of these species and their habitat is an urgent task, as well as the characterization and evaluation of these genetic resources.

A method for seedling recovery in Jatropha curcas after cryogenic exposure of the seeds

Actually, the germplasm of Jatropha spp. is conserved as whole plants in field collections. Under this storage method, the genetic resources are exposed to disease, pest and natural hazards such as human error, drought and weather damage. Besides, field genebanks are costly to maintain and with important requirements of trained personnel. Thus, the development of efficient techniques to ensure its safe conservation and regeneration is therefore of paramount importance. In this work we describe a method for Jatropha curcas seeds cryoexposure and seedling recovery after thawed. In a first experiment, an efficient protocol for in vitro plant recovery was carried out using zygotic embryo or seeds with or without coat. In a second experiment, desiccated seeds with or without coat were exposed to liquid nitrogen and evaluated after cryoexposure. Germination percentages were variable among treatments, and seeds demonstrated tolerance to liquid nitrogen exposure under certain conditions. Seeds of J. curcas presented up to 99.6% germination after seed coat removal. Seeds with coat cultured in vitro did not germinate, and were 60% contaminated. The germination of the zygotic embryos was significantly higher in the ½ MS medium (93.1%) than in WPM medium (76.2%), but from zygotic embryo, abnormal seedlings reached up to 99%. Seeds with coat exposed to liquid nitrogen showed 60% germination in culture after coat removal with good plant growth, and seeds cryopreserved without coat presented 82% germination, but seedlings showed a reduced vigor and a significant increase in abnormal plants. Seeds cultured in vitro with coat did not germinate, independently of cryoexposure or not. This study reports the first successful in vitro seedling recovery methodology for Jatropha curcas seeds, after a cryopreservation treatment, and is recommended as an efficient procedure for in vitro plant recovery, when seeds are conserved in germplasm banks by low or cryotemperatures.

Actualmente, el germoplasma de las especies de Jatropha ssp. se conserva como plantas enteras en las colecciones de campo. Bajo este método de almacenamiento, los recursos genéticos están expuestos a enfermedades, plagas y desastres naturales tales como el error humano, la sequía y las inclemencias del tiempo. Además, los bancos de germoplasma de campo son costosos de mantener y requieren bastante personal capacitado. Por lo tanto, el desarrollo de técnicas eficientes para asegurar su conservación segura así como su regeneración, es de suma importancia. En este trabajo se describe un método de recuperación para semillas y plántulas crioexpuestas de Jatropha curcas después de descongeladas. En un primer experimento, se llevó a cabo un protocolo eficiente para la recuperación de plantas in vitro mediante el uso de embriones cigóticos o semillas con o sin testa. En un segundo experimento, las semillas disecadas, con o sin testa fueron expuestas a nitrógeno líquido y se evaluaron después de la crioexposición. Los porcentajes de germinación fueron variables entre los tratamientos, y las semillas demostraron tolerancia a la exposición del nitrógeno líquido bajo ciertas condiciones. Las semillas de J. curcas presentaron hasta un 99.6% de germinación después de la eliminación de la testa. Las semillas con la testa cultivadas in vitro no germinaron, y el 60% se contaminaron. La germinación de los embriones cigóticos fue significativamente alta en el medio ½ MS (93.1%) en comparación con el medio WPM (76.2%), pero desde los embriones zigóticos, las plántulas anormales alcanzaron más del 99%. Semillas con la testa inmersa en nitrógeno líquido mostraron un 60% de germinacion en cultivos despúes de la remoción de la testa con un buen crecimiento de la planta, y las semillas criopreservadas sin testa presentaron un 82% de germinación, pero las plántulas mostraron un reducido vigor y un incremento significativo de plantas anormales. Semillas con testa cultivadas in vitro no germinaron, independientemente de la criopreservación o no. Este estudio reporta el primer éxito in vitro de una metodología de recuperación de plántulas para semillas de Jatropha curcas, después de un tratamiento de criopreservación, que se recomienda como un procedimiento eficaz para la recuperación de plantas in vitro, cuando las semillas se conservan en bancos de germoplasma a bajas o crio-temperaturas.

Estudo da divergência genética por características morfológicas entre acessos de mentrasto (Ageratum conyzoides L. ) coletados no estado do Tocantins em diferentes épocas / Genetic divergence study by morphologic traits among mentrasto (Ageratum conyzoides L. ) accessions collected in the state of Tocantins in different period

Este trabalho objetivou avaliar a divergência genética entre nove acessos de mentrasto (Ageratum conyzoides) por métodos multivariados utilizando caracteres morfológicos, em quatro épocas de colheita. Os nove acessos de mentrasto foram obtidos de plantas que ocorrem naturalmente nas cinco regiões climáticas do Estado do Tocantins. Em cada época de colheita foram avaliadas as características como biomassa fresca da parte aérea, biomassa seca, área foliar, número de folhas, floração e altura. Pela análise de agrupamento (método de Tocher) foram formados dois grupos na primeira e quarta épocas de colheita, três grupos na segunda época e quatro grupos na terceira época de colheita. Observou-se variação na constituição dos grupos pelos acessos nas épocas de colheita. A divergência genética entre acessos de mentrasto, avaliada por caracteres morfológicos, foi influenciada pelo estádio de desenvolvimento da espécie. A existência de variabilidade entre os acessos coletados em diferentes localidades fornece subsídio para a coleta sistematizada de germoplasma em A. conyzoides no Estado do Tocantins.

This study aimed to analyze the genetic divergence among nine mentrasto (Ageratum conyzoides) accessions by multivariate methods using morphologic traits for four harvesting periods. The nine accessions of mentrasto were obtained from plants that occur naturally in five climatic regions of the state of Tocantins. At each harvesting period, the following traits were evaluated: fresh biomass of the aerial part, dry biomass, leaf area, number of leaves, flowering and height. The grouping analysis (Tocher's method) identified two groups, in the first and fourth harvest periods, three groups in the second harvest period and four groups in the third harvest period. Variation was observed for the group constitutions among the different harvesting periods. The genetic divergence among mentrasto accessions, evaluated by morphologic traits, was influenced by developmental stage of specie. The existence of genetic variability among accessions from different regions supports the systematic collection of A. conyzoides germplasm in the state of Tocantins.