Summary Tuberose (Polianthes tuberosa L.) is an ornamental plant produced worldwide, mainly as a cut flower. A limitation of tuberose production is the control of flowering time, for which different strategies have been evaluated, one of these is the pretreatment of the corms with temperature. In this study, corms of tuberose were subjected to two storage temperatures (4 and 27 °C) for 4, 5, 6 and 7 weeks, in addition to two controls: corms kept at room temperature (T0) and corms with a pretreatment with GA3 (200 ppm). The variables evaluated were meristem length (ML), meristem width (MW), days to sprouting (DS), days to flowering (D), flower stem length (FSL), flower stem diameter (FSD), spike length (SL) and number of flowers (NF). The fastest growth and differentiation of the meristem occurred after the establishment of corms in the greenhouse; treatments at 27 °C advanced the sprouting of the first leaves. The treatments of 27 °C for six weeks and 4 °C for one week showed fewer days to flowering (100.8 and 104.0 respectively). In general, corms treated at 27 °C showed greater homogeneity in the harvest curve without affecting the rest of the variables evaluated, which is important because such treatments can be used to control tuberose flowering without affecting quality.

Resumen El nardo (Polianthes tuberosa L.) es una planta ornamental producida en todo el mundo, principalmente como flor de corte. Una limitante de la producción de nardo es el control del tiempo de floración, para lo cual se han estudiado diferentes estrategias, una de estas es el pretratamiento de los cormos con temperaturas. En el presente estudio, cormos de nardo se sometieron a dos temperaturas de almacenamiento (4 y 27 °C) por 4, 5, 6 y 7 semanas, además de dos testigos: cormos mantenidos a temperatura ambiente (T0) y cormos con pretratamiento con AG3 (200 ppm). Las variables evaluadas fueron el largo del meristemo (LM), ancho del meristemo (AM), días a la brotación (DAB), días a floración (DAF), longitud del tallo floral (LT), diámetro del tallo (DT), longitud de la espiga (LE) y número de flores (NF). El mayor crecimiento y diferenciación del meristemo se presentaron después del establecimiento de los cormos en invernadero; los tratamientos a 27 °C adelantaron la brotación de las primeras hojas. Los tratamientos de 27 °C por 6 semanas y de 4 °C por una semana presentaron menores días a floración (100.8 y 104.0 respectivamente). En general, los cormos tratados a 27 °C presentaron mayor homogeneidad en la curva de cosecha sin afectar el resto de las variables evaluadas, lo cual es importante porque tales tratamientos pueden usarse para controlar la floración de nardo sin afectar la calidad.

Abstract Antioxidant capacity (AC) was determined by the ABTS method and DPPH, and total phenol content (TPC) in dehydrated plant material, in infusions and in residues (plant material after preparing the infusion) of white, black, red, green, spearmint, stevia, lemon grass and chamomile teas to which stevia leaves were added or not added; addition of processed stevia powder was also tested. Three independent experiments were set up: with dehydrated plant material, with infusions and with residues. For the case of dehydrated plant material, white tea had the highest TPC (10813.5 mg GAE/100g) and AC by the ABTS method (1183.3 µM TE/g) and DPPH method (1525.0 µM TE/g). In infusions, black tea had higher TPC (180.82 µg GAE/ml) and AC by the methods ABTS and DPPH (0.6114 and 2.5983 µM TE/ml, respectively). In residues, TPC was higher in white tea, while green tea had the highest AC values. AC of dehydrated plant material increased when stevia leaves were added, according to the DPPH and ABTS methods, but not in residues by ABTS. Addition of stevia leaves in infusions increased AC in white, lemon grass, chamomile and stevia teas by the ABTS method and in spearmint, black, red, and green teas with the DPPH method.

Abstract Virgin oil from avocados (Persea americana Mill.) is obtained by mechanical processes after pulp malaxation at temperatures that minimize oxidation and improve separation. The objective of this study was to assess the effect of time (0, 20, 30, 40, 60, 120 and 180 min) and temperature (40 and 50 °C) conditions during pulp malaxation on extraction yield, nutritional value (normalized fatty acid profile) and specific extintion (K232 and K270) of virgin oil extracted under laboratory conditions from avocados cultivated in southern Jalisco, Mexico. When pulp was malaxated for 120 min at 40 and 50 °C, a larger proportion of oil was extracted (82.9 ± 0.3% and 80.2 ± 0.8%, respectively). We observed that the normalized percentage of the fatty acids linoleic (18 ± 2%) and linolenic (1.2 ± 0.2%) decreased with mixing time, while that of palmitoleic (9 ± 1%), oleic (51.6 ± 1.2%) and stearic (0.5 ± 0.1%) remained without change. The ω-6:ω-3 ratio (15 ± 1) was higher than the recommended values but similar to those reported as favorable for health. Specific extinction (K232, 2.2 ± 0.3 and K270, 0.20 ± 0.03) indicate that the oxidation level remained low. Malaxation at 40 or 50 °C did not significantly alter the characteristics of the oil, but time significantly affected yield.

Freeze-drying technology is the best dehydration process to preserve shelf-life and allowing avocado to maintain its sensorial and nutritional characteristics. The aim of this work was to determine if the freeze-drying and production condition have an effect on the nutritional quality of the avocado pulp grown in rain-fed and irrigation orchards. Four treatments were applied: non-freeze-dried rain-fed fruits, non-freeze-dried irrigation fruits, freeze-dried rain-fed fruits and freeze-dried irrigation fruits. Results showed that the fruit is made up of 71.4%, 16%, and 12.6% pulp, seed and skin, respectively. The pulp is made up of 71.51%, 19.96%, 2.81%, 0.51% and 1.51% water, lipids, ashes, crude fiber and protein, respectively. Avocado oil is composed by 61%, 18.8%, 11.6% and 7% oleic, palmitic, linoleic, and palmitoleic fatty acids, respectively. The freeze-drying decreased the linoleic acid by 1.43 g/100g. Under rain-fed conditions 4% and 13% less total fat and oleic fatty acid are produced than in irrigation conditions. We conclude that freeze-dried avocado pulp shows slight changes in their nutritional quality.

La tecnología de liofilización es el mejor proceso de deshidratación para mantener mayor vida de anaquel y conservar las propiedades nutricionales y sensoriales de la pulpa del aguacate. El objetivo de este estudio fue determinar si el liofilizado y condición de producción tienen un efecto sobre la calidad nutrimental de la pulpa de aguacate cultivado en huertas de riego y temporal. Se aplicaron 4 tratamientos: frutos de temporal no liofilizado, frutos de riego no liofilizado, frutos liofilizados de temporal y frutos liofilizados de riego. Los resultados muestran que el fruto está compuesto por 71.39, 16 y 12.6% de pulpa, hueso y cascara respectivamente. La pulpa está compuesta por 71.51, 19.96, 2.81, 0.51 y 1.5 % de humedad, lípidos, cenizas, fibra cruda y proteína, respectivamente. El aceite del aguacate está constituido de 61. 18.8, 11.6 y 7% de ácidos grasos oleico, palmítico, linoléico y palmitoleico, respectivamente. El liofilizado disminuyó 1.43 g/100 g de ácido linoléico. Bajo condiciones de temporal se produce 4 y 13% menos grasa total y ácido graso oleico que en condiciones de riego. Se concluye que la pulpa del aguacate liofilizada presenta ligeros cambios en su calidad nutrimental.

Drought is a major constraint for common bean (Phaseolus vulgaris L.) production in México. Dehydrins are constitutive or stress-induced proteins related with a protective role of membranes and macromolecules against denaturation, thus preventing loss of their function. In this work, seed production and patterns of dehydrins accumulation in leaves and pods were evaluated in common bean cv. 'Otomí' subjected to drought, as compared with well-irrigated plants. Drought applied at pod formation and seed filling (SF) reduced yield up to 57 %. An antibody against a consensus sequence present in most dehydrins allowed for dehydrin identification. Two dehydrins of 82 and 73 kDA turned up both in leaves and pods throughout all the evaluated conditions. Presumably, both dehydrins are constitutive in the 'Otomí' cultivar. These dehydrins showed higher expression than controls in leaves after 6 d of drought at seedling and SF stages, and in pods 6 d after drought had started at SF. Increased expression might provide better protection during early stages of seedling and seed development. Increments on 63, 36 and 22 kDa dehydrin expression in pods at late SF might coincide with plant developmental programs, which prepare seed for desiccation. Dehydrins of 158, 54, 46, and 41 kDa were detected in pods 10 d after floral opening as a transient response to drought stress in SF. These results indicate dehydrins are relevant during plant development, as well as during drought stress.

La sequía es el factor más limitante de la productividad de frijol (Phaseolus vulgaris L.) en México. Las dehidrinas son proteínas constitutivas o inducibles por diferentes tipos de estrés, relacionadas con la protección a membranas y macromoléculas contra la desnaturalización, que evitan la pérdida de función. En este trabajo se estudió el efecto de la sequía aplicada en diferentes etapas de desarrollo, sobre la producción de semilla y los patrones de acumulación de dehidrinas en hojas y vainas de frijol cv. 'Otomí', comparado con plantas irrigadas. La sequía aplicada durante el período de formación de vainas y llenado de semilla (SF), redujo hasta 57 % el rendimiento. Las dehidrinas fueron identificadas con un anticuerpo que reconoce una secuencia consenso presente en la mayoría de ellas. Dehidrinas de 82 y 73 kDa fueron detectadas en hojas y en vainas en todas las condiciones evaluadas, por lo que se consideran constitutivas del cultivar 'Otomí'. Estas dehidrinas presentaron mayor expresión que el control en hojas a los 6 d de sequía aplicada en los estadios de plántula y SF, y en vainas también a los 6 d de sequía aplicada en SF. Estos incrementos podrían ser necesarios para brindar mejor protección en etapas tempranas del desarrollo de la plántula y la semilla. Incrementos en dehidrinas de 63, 36 y 22 kDa observados en vainas durante la etapa de SF, podrían ser parte del programa de desarrollo de la planta encargado de preparar a la semilla para la desecación. En vainas se detectaron dehidrinas de 158, 54, 46 y 41 kDa a los 10 d después de la apertura floral, como una respuesta transitoria al estrés hídrico en SF. Estos resultados indican que las dehidrinas de frijol son relevantes durante el desarrollo de la planta y durante condiciones de estrés por sequía.

Se evaluaron 63 cultivares de mandarina (Citrus spp.) provenientes de la colección del Campo Citrícola Experimental Francisco Villa, Tamaulipas, México, usando marcadores morfológicos y AFLP (Amplified Fragment Length Polymorphism). Se usaron 20 caracteres cuantitativos y 10 cualitativos de hojas, flores y frutos. Las mejores combinaciones de iniciadores AFLP fueron la Mse +CAG más Eco +ACA, y Mse +CAA más Eco +AGG, dando un total de 109 bandas con un 86% de polimorfismo. Tanto los marcadores morfológicos como los moleculares mostraron un alto grado de variación entre los individuos analizados, lo que indica una importante fuente de diversidad genética que puede ser utilizada en futuros programas de mejoramiento genético. Aunque la comparación de los datos morfológicos y moleculares usando la prueba de Mantel no mostró una correlación significativa (r= 0.31), ambas técnicas parecen ser complementarias para la caracterización de mandarinas.

Sixty-three mandarin (Citrus spp.) cultivars from the collection of the Campo Citrícola Experimental Francisco Villa, Tamaulipas, Mexico, were evaluated using morphological and Amplified Fragment Length Polymorphism (AFLP) markers. Twenty quantitative and 10 qualitative morphological characters from leaves, flowers and fruits were evaluated. The Mse +CAG plus Eco +ACA, and Mse + CAA plus Eco + AGG AFLP primers were the best combinations and generated 109 bands with 86% polymorphism. Both morphological and molecular analysis showed a high degree of variation among analyzed accessions, indicating an important source of genetic diversity that can be used in future breeding programs. Although comparison of morphological and molecular data using the Mantel test did not indicate a significant correlation (r= 0,31), both techniques appeared to be complementary for mandarin characterization.

Avaliaram-se 63 cultivares de mandarina (Citrus spp.) da coleção do Campo Citrícola Experimental Francisco Villa, Tamaulipas, México utilizando marcadores morfológicos e AFLP (Amplified Fragment Length Polymorphism). Avaliaram-se 20 caracteres quantitativos e 10 qualitativos em folhas, flores e frutos, os quais mostraram um alto nível de variação entre os materiais avaliados. As combinações Mse +CAG mais Eco +ACA, y Mse +CAA mais Eco +AGG foram as melhores gerando 109 bandas com um polimorfismo de 86%. Tanto a análise morfológica como a molecular mostraram um alto nível de variação indicando a existência de uma fonte importante de diversidade genética que pode ser usada em futuros programas de melhoramento. Mesmo que a comparação dos dados morfológicos e moleculares utilizando a prova de Mantel indicou uma correlação baixa entre estes (r=0,31), ambas as técnicas parecem ser complementarias para a caracterização de mandarinas.