Performance of yam microtubers from temporary immersion system in field conditions

The yam clones ´Pacala Duclos´ and ´Belep´ of Dioscorea alata were used to evaluate the performance of microtubers formed in temporary immersion systems (TIS) in field conditions. Previously sprouted microtubers with a fresh weight higher than 3.0 gFW were used while in vitro plants and tuber crowns from conventional propagation methods served as control. In both clones there were no significant differences in qualitative morphological characters between plants from microtubers and in vitro plants for all traits but both differed significantly from plants obtained from tuber crowns. The same trend was observed for number, length, diameter and fresh weight of tubers produced 36 weeks after field planting. The number of tubers formed per plant raised from microtubers doubled that raised from tuber crowns in both clones. Microtubers from temporary immersion systems can be grown on the field and used in original seed production programs.Key words: Microtuber, yam, field, temporary immersion system

Isolated diaphragm weakness and the diagnostic value of phrenic nerve stimulation

Acute onset, atraumatic, bilateral diaphragm paralysis due to isolated bilateral phrenic neuropathy is uncommon. Respiratory physicians should be alert to this disorder because it is associated with considerable morbidity and diagnosis is often delayed. These case reports highlight important aspects of the presentation, investigations and management of this disorder

Effects of different culture conditions (photoautotrophic, photomixotrophic) and the auxin indole-butyric acid on the in vitro acclimatization of papaya (Carica papaya L. var. Red Maradol) plants using zeolite as support

Plant regeneration of papaya via organogenesis and somatic embryogenesis has been successful;  however, the biggest problem of in vitro culture of this species is the acclimatization of regenerated  plants, where over 70% of the plants are lost before being planted in the field. Decreasing the relative humidity inside the culture vessel and thus increasing the ventilation, appears to have a greater effect on  the adaptation of papaya plants, strengthening the function of the stomata and with this, allowing better  control of water loss from the leaves. The aim of this study was to determine the effects of different  concentrations of sucrose and indole-butyric acid (IBA) on rooting and in vitro acclimatization of plants  using sterile zeolite as support and culture vessels with increased ventilation. Three concentrations of  sucrose (0, 10 and 20 g L-1) were studied with and without auxin and as the control treatment, the  rooting culture medium with agar during 17, 27 and 37 culture days. The highest percentage of rooting  was recorded at 37 culture days in the treatment without sucrose and IBA with 80.0% and zeolite as  support. The best photosynthetic values were achieved when in vitro shoots were grown in culture  medium with auxin and different concentrations of sucrose, even though they were also high in the  treatment without the presence of IBA and without sucrose at 17 days of culture. The combined effect of the zeolite, auxin (IBA), without sucrose in the culture medium and increased ventilation allowed   photoautotrophic culture conditions which had effect of the increasing plant survival under ex vitro  acclimatization conditions.Key words: Carica papaya, photosynthesis, roots formation

Determinación por AFLP de la estabilidad genética de plantas de yuca obtenidas por embriogenesis somática y organogenesis

AFLP techniques have been reported to determine the genetic stability at a molecular level of cassava plants propagated by several methods: somatic embryogenesis, organogenesis and field conditions. ‘CMC-76’, ‘CEMSA 74-725’ and ‘Señorita’ clones from the germplasm collection kept at the INIVIT were used. Two Kit for AFLPs were applied, one of them combined selection primers +2/+3 (AFLP Analysis System II GibcoBRL) and the other +3/+3 (AFLP® Analysis System I, GibcoBRL®). 44 combination primers (EcoRI + 2 ó EcoRI + 3) were tested and five were selected as the most efficient. Plants derived from different propagation methods within each clone resulted identical genetically and differences were only observed in the three studied clones. This result corroborates the efficiency of AFLPs to study the genetic stability of micropropagated material, storaged at medium term or in cryoconservation. Besides, plants obtained with these techniques can be used for the production of high quality planting material in this crop.Key word: genetic stability, organogenesis, somatic embryogenesisSe describe el empleo de la técnica de AFLP para determinar a nivel molecular la estabilidad genética de las plantas de yuca (Manihot esculenta, Crantz) propagadas por diferentes métodos: embriogénesis somática, organogénesis y tradicional en campo. Se utilizaron los clones CMC-76, CEMSA 74-725 y Señorita del banco de germoplasma del INIVIT. Se aplicaron dos Kit para AFLP, uno con una combinación de cebadores de selección +2/+3 (AFLP® Analysis System II, GibcoBRL®) y otro +3/+3 (AFLP® Analysis System I, GibcoBRL®). Se estudiaron 44 combinaciones de cebadores (EcoRI+2 ó EcoRI+3 x MseI+3) y se seleccionaron cinco como los más eficientes. Se encontró que las plantas procedentes de los diferentes métodos de propagación estudiados dentro de cada clon, resultaron genéticamente idénticas y sólo fueron observadas diferencias entre los tres clones estudiados. Este resultado confirmó la utilidad de los AFLP para el estudio de la estabilidad genética de los materiales micropropagados, conservados a mediano plazo o crioconservados. Además, las plantas obtenidas por estas técnicas pueden ser utilizadas para la producción de material de plantación de alta calidad en este cultivo.Palabras clave: embriogénesis somática, estabilidad genética, Manihot esculenta, organogénesi

The mental health of university students in the United Kingdom

There are increasing concerns globally about the mental health of students (Kadison,& Digeronimo, 2004). In the UK, the actual incidence of mental disturbance is unknown, although university counselling services report increased referrals (Association of University & College Counselling, 2011). This study assesses the levels of mental illness in undergraduate students to examine whether widening participation in education has resulted in increases as hypothesized by the UK Royal College of Psychiatrists (2003, 2011). Patterns of disturbance across years are compared to identify where problems arise. Students (N = 1197) completed the General Health Questionnaire-28 either on day one at university or midway through the academic year for first, second and third year students. Rates of mental illness in students equalled those of the general population but only 5.1% were currently receiving treatment. Second year students reported the most significant increases in psychiatric symptoms. Factors contributing to the problem are discussed

Establecimiento de un banco clonal de Caesalpinia spinosa (Mol.) O. Kuntz mediante selección de árboles plus e injerto

In Ecuador, plant propagation techniques are not available commercially to establish clonal banks of Caesalpinia spinosa (Mol.) O. Kuntz (guarango) plus trees, which limits the development of in vitro propagation protocols of this specie. The objective of the present work was to establish a clonal bank of C. spinosa by selecting plus trees and grafting. Guarango trees belonging to the province of Chimborazo, Guano canton were selected based on total height, height at the beginning of the crown, height of crown, crown surface, crown symmetry, flowering, fruit production and content of tannins in the pod. The patron plants to make the grafts were obtained from scarified seeds, soaked for 48 hours at room temperature and planted in beds of 1.0 x 3.0 m. At 40 days, the seedlings were transplanted into pockets and at 16 months the grafts were made in the patron plants. Three types of graft were used (simple slit in the patron, single slit in the spike and bud grafting). For each, 100 patron were used. Of the eight trees plus collected in the field, the ecotype CHSt03 was used to make the grafts. It was showed the highest total height (6.6m), height at the beginning of the cup (2.2m), cup surface ( 70%), cup volume ( 10%), cup symmetry (1), fruit (40kg / tree) and total polyphenol content in pods (5870 μgEAGgMS-1). The graft by simple slit in the patron had the highest stuck percentage (80%). These results allowed to establish a clonal bank of 80 plants grafted of C. spinosa of the ecotype CHSt03, which establish the bases to develop protocols for in vitro propagation of this forest species, native of Ecuador. Keywords: biodiversity, biotechnology, forestry, industry, tanninsEn Ecuador no se dispone de técnicas de propagación de plantas a nivel comercial que permitan establecer bancos clonales de árboles plus de Caesalpinia spinosa (Mol.) O. Kuntz (guarango), lo cual limita el desarrollo de protocolos de propagación in vitro de esta especie. El objetivo del presente trabajo fue establecer un banco clonal de C. spinosa mediante la selección de árboles plus e injerto. Se seleccionaron árboles plus de guarango pertenecientes a la provincia de Chimborazo, cantón Guano, en base a la altura total, altura al comienzo de la copa, altura de copa, superficie de copa, simetría de copa, floración, producción de frutos y contenido de taninos en la vaina. Las plantas patrones para realizar los injertos se obtuvieron a partir de semillas escarificadas, remojadas durante 48 horas a temperatura ambiente y sembradas en camas de 1.0 x 3.0 m. A los 40 días, las plántulas fueron trasplantadas a bolsas y a los 16 meses se realizaron los injertos en las plantas patrones. Se utilizaron tres tipos de injerto (hendidura simple en el patrón, hendidura simple en la púa y escudete). Por cada uno se usaron 100 patrones. De ocho árboles plus colectados en campo se seleccionó el ecotipo CHSt03 para realizar los injertos, pues fue quien mayor altura total (6.6m), altura al comienzo de la copa (2.2m), superficie de copa (70%), volumen de copa (10%), simetría de copa (1), Frutos (40kg/árbol) y contenido de polifenoles totales en vainas (5870 µgEAGgMS-1) mostró. El injerto mediante hendidura simple en el patrón tuvo el mayor porcentaje de prendimiento (80%). Estos resultados permitieron establecer un banco clonal de 80 plantas injertadas de C. spinosa del ecotipo CHSt03, lo cual sienta las bases para desarrollar protocolos de propagación in vitro de esta especie forestal, nativa de Ecuador. Palabras clave: biodiversidad, biotecnología, forestal, industria, tanino

Regeneración de plantas via embriogénesis somática en Phaseolus acutifolius A. Gray

Plant regeneration protocols are a requirement to develop plants transformation systems.The capacity of Phaseolus acutifolius A. Gray to regenerate plants from embryogenic callus formation was investigated. Two explants were used to form calli on a culture medium containing thidiazuron and indole-3-acetic acid. The embryonic axes showed better capacity than cotyledons to form embryos. Solar light was the most favourable to develop the in vitro plants. The 32% of somatic embryos with complete germination was achieved. These results indicate that somatic embryos formation and their germination in Phaseolus acutifolius A. Gray depended on the explant, culture medium and illumination conditions. In vitro-germinated plantlets were established in the greenhouse.Key words: bean, callus formation, plant regeneration, tissue culturePara desarrollar un sistema de transformación genética un requisito fundamental es contar con un protocolo de regeneración de plantas. En el trabajo se investigó la capacidad de Phaseolus acutifolius para regenerar plantas a partir de callos con estructuras embriogénicas. Se utilizaron dos tipos de explantes para la formación de callos en un medio de cultivo que contenía thidiazuron y ácido indol-acético. Los ejes embrionarios mostraron una mejor capacidad que los cotiledones para la formación de embriones somáticos. La luz solar resultó ser la más favorable para el desarrollo de las plantas in vitro. En estas condiciones se alcanzó el 32% de los embriones somáticos con germinación completa. Estos resultados indicanron que la formación de embriones somáticos y su germinación en Phaseolus acutifolius dependieron del explante, el medio de cultivo y las condiciones de iluminación. Las plantas germinadas in vitro, pudieron ser aclimatizadas en el invernadero.Palabras clave: cultivo de tejidos, formación de callos, frijol, regeneración de plantasAbbreviations: BAP 6- Benzylaminopurine, TDZ Thidiazuron, IAA indole-3-acetic acid, GA3 gibberellic acid, AgNO3 silver nitrat

FitoMas-E: una alternativa para el enraizamiento in vitro de cultivares de caña de azúcar

FitoMas-E increases and accelerates the germination of the seeds, stimulates the development of roots, stems, leaves and improves the nutrition of plants.The objective of this work was to evaluate the effect of FitoMas-E on the in vitro rooting of sugarcane cultivars ‘CP52-43’, ‘C87-51’ and ‘C1051-73’. A completely randomized experimental design was used with four treatments, three concentrations of FitoMas-E (0.5, 1.0 and 1.5 ml l-1) and indoleacetic acid (IAA) 1.3 mg l-1 as control in the liquid culture medium, with five repetition. At 15 days of culture the number of rooted shoots, height, leaves number and length of roots were evaluated. In the ex vitro acclimatization stage, its were quantified the number of plants with root, leaves and roots number per plant and it was measured the height after 45 days of transplanted. The results showed that the Fitomas-E in the cultivars 'CP52-43' and 'C87-51' achieved a number of shoots with a root similar to the control and in 'C1051-73' it exceeded it with the concentration of 0.5 ml l-1 of this biostimulant. Leaf height, leaves number and root length reached values significantly higher than control, with 1.0 ml l-1 phytostimulant, except for 'CP52-43' where similar root length was achieved among treatments. In the ex vitro acclimatization stage the in vitro plants rooted with the FitoMas-E achieved the required quality parameters, exceeding the controls for the variables height, number of roots and length of the longest root. Among genotypes there were significant differences for all cultivars. Keywords: in vitro culture, micropropagation, Saccharum spp.FitoMas-E incrementa y acelerar la germinación de las semillas, estimula el desarrollo de las raíces, tallos, hojas y mejora la nutrición de las plantas. El objetivo del trabajo fue determinar el efecto del FitoMas-E sobre el enraizamiento in vitro de caña de azúcar cv. ‘CP52-43’, ‘C87-51’ y ‘C1051-73’. Se utilizó un diseño experimental completamente aleatorizado con cuatro tratamientos, tres concentraciones de FitoMas-E (0.5, 1.0 y 1.5 ml l-1) y 1.3 mg l-1 de ácido indolacético como control en el medio de cultivo líquido, con cinco repeticiones. A los 15 días de cultivo se cuantificó el número de brotes con raíz, longitud de la raíces, altura del brote y el número de hojas. En la fase de aclimatización ex vitro, se cuantificó el número de plantas con cepellón, número de hojas, raíces y se midió la altura de la planta a los 45 días de trasplantadas. Los resultados mostraron que el Fitomas-E en los cultivares ‘CP52-43’ y ‘C87-51’ logró un número de brotes con raíz similar al control y en ‘C1051-73’ lo superó con la concentración de 0.5 ml l-1 de este bioestimulante. La altura del brote, el número de hojas y la longitud de la raíz, alcanzaron valores significativamente superiores al control, con 1.0 ml l-1 del fitoestimulante, excepto en ‘CP52-43’ donde se logró longitud de la raíz similar entre tratamientos. En la fase de aclimatización ex vitro las plantas in vitro enraizadas con el FitoMas-E lograron los parámetros de calidad requeridos y superaron a los controles para las variables altura, número de raíces y longitud de la raíz más larga. Entre genotipos hubo diferencias significativas para todos los cultivares. Palabras clave: aclimatización ex vitro,  cultivo in vitro, Saccharum spp

Embriogénesis somática en el cv. Navolean a partir de ápices de brotes de yemas axilares

In order to develop embryogenic cultures in AAB Musa genotypes without persistent male inflorescence, the process has had greater success from proliferating meristems for callus formation with embryogenic structures. Based on the previous information, other alternative explant sources for somatic embryogenesis development in cv. Navolean. Meristematic apexes were cultured in p5 culture medium supplemented with thidiazuron and ancymidol (0.2, 0.4, 0.6, mg.l-1) to obtain axillary buds. Later, axillary buds and proliferated meristems were tested for callus induction with embryogenic structures combinations with different 2,4-D concentrations. The best growth regulator for obtaining axillary buds was ancymidol (0.2 mg.l-1). For callus formation with embryogenic structures, axillary buds at 1.0 mg.l-1 2,4-D provided a higher percentage (13.6%). These results permitted the development of embryogenic cell suspensions from somatic embryos.Key words: Ancymidol, embryogenic cell suspension, plantainEl desarrollo de cultivos embriogénicos en los genotipos AAB de Musa, que no poseen inflorescencia masculina persistente, ha tenido mayor éxito a partir de multiyemas para la formación de los callos con estructuras embriogénicas pero esto pudiera incrementar la variación somaclonal. Teniendo en cuenta lo anterior se trabajó en la determinación de otra fuente de explante inicial alternativa para el desarrollo de la embriogénesis somática en el cultivar objeto de estudio. Se cultivaron brotes axilares en el medio de cultivo P5 suplementado con tidiazuron y ancimidol (0.2; 0.4; 0.6 mg.l-1 cada uno por separado) para lograr la brotación de yemas axilares. Posteriormente para formar los callos con estructuras embriogénicas se colocaron los ápices de brotes obtenidos de yemas axilares en un medio de cultivo ZZ con diferentes concentraciones de 2,4-D. El mejor regulador del crecimiento para la brotación de yemas axilares fue el ancimidol (0.2 mg.l-1). Para la formación de callos con estructuras embriogénicas, la concentración de 1.0 mg.l-1 de 2,4-D propiciaron el mayor porcentaje (13.6%). A partir de los embriones somáticos producidos se logró el establecimiento de suspensiones celulares embriogénicas. Se demostró que es posible el desarrollo de la embriogénesis somática en el cv. Navolean no solo a partir de scalps de multiyemas.Palabras clave: ancimidol, plátanos, suspensiones celulares embriogénica