Time to flowering of ornamental orchids

Objective: To analyze features of time to flowering of orchids and some strategies for its control in cultivation for ornamental purposes. Design/methodology/approach: Information from various authors and our own data is shown, in relation to the management of flowering time of ornamental orchids, based on treatments of environmental effects, plant growth regulators (PGRs) and nutrition. Findings/conclusions: It is possible to reduce the flowering time of orchids by environmental modifications, mainly temperature and photoperiod. This can also be achieved by nutritional management, mainly macro-nutritional, and through organic nutrition and PGRs. However, much more information is needed, especially for native orchid species with ornamental potential.&nbsp

Riqueza de la familia Orchidaceae en un bosque mesófilo de montaña en Chocamán, Veracruz, México

Background and Aims: Some fragments of cloud forest (CF) in central Veracruz have not been studied floristically. The aim of the present investigation was to record the richness of orchids in a fragment of this type of forest in Chocamán, Veracruz.Methods: Specimens were collected and scientific collections and bibliographic information were revised.Key results: The list included 36 species, belonging to 25 genera. Epidendrum was the genus with more species (7), followed by Dichaea, Lycaste, Oncidium, Prosthechea and Stelis, with two each one, and all other genera were represented by one species. Four species are endemic to Mexico (Epidendrum longipetalum, Gongora galeata, Oncidium incurvum and Trichocentrum pachyphyllum); and two are protected by the Mexican legislation (O. incurvum and Stanhopea oculata). Epidendrum magnoliae and Epidendrum cf. radioferens are new records for the Veracruz flora.Conclusions: The orchid flora studied here faces problems because of the land-use change and illegal extraction for trade, thus conservation measures are urgent.Antecedentes y Objetivos: Existen fragmentos de bosque mesófilo de montaña (BMM) en el centro de Veracruz que no se han estudiado florísticamente. El objetivo de la presente investigación fue registrar la riqueza de orquídeas en un fragmento de este tipo de bosque en Chocamán, Veracruz.Métodos: Se hizo trabajo de recolección de ejemplares, así como revisión de colecciones científicas e información bibliográfica.Resultados clave: El listado incluyó 36 especies pertenecientes a 25 géneros. Epidendrum fue el género con mayor número de especies (7), seguido por Dichaea, Lycaste, Oncidium, Prosthechea y Stelis, con dos cada uno, el resto de los géneros estuvo representado por una. Cuatro especies son endémicas de México (Epidendrum longipetalum, Gongora galeata, Oncidium incurvum y Trichocentrum pachyphyllum), y dos están protegidas por la legislación mexicana (O. incurvum y Stanhopea oculata). Epidendrum magnoliae y Epidendrum cf. radioferens son nuevos registros para la flora de Veracruz.Conclusiones: La orquideoflora aquí estudiada enfrenta problemas debido al cambio de uso de suelo y la extracción ilegal para comercio, por lo que urgen medidas para su conservación

Fertilization methods and substrate particle size differentially affect growth and macronutrient status of Laelia anceps subsp. anceps

The effects of three fertilization methods (FM) using the Peters Professional® 30N-10P-10K water soluble fertilizer were analyzed: fertilization in irrigation water (FIW), foliar fertilization (FF), and their combination (FIW + FF), as well as two substrate particle sizes (SuPS): larger particle size (LPS) and smaller particle size (SPS), on the growth and macronutrient status of Laelia anceps subsp. anceps (Orchidaceae). A 3 × 2 factorial experiment was established. Aerial and root growth, dry weight and concentration of macronutrients N, P, K, Ca, and Mg in leaves, pseudobulbs, and roots were all evaluated. The interaction of the study factors resulted in a greater number of leaves, while by simple effects, greater leaf area, number of pseudobulbs, root volume, and dry matter of leaves and roots were obtained, when FIW and LPS were used. With FF, greater growth in root volume was observed. There were no differences in the concentration of N in the growth organs analyzed, but due to the interaction of factors, a higher concentration of P, K, Mg, and S was observed in roots, mainly with FIW + FF and SPS; although for P, there was a higher concentration in FIW and LPS. In the case of SPS, the concentrations of K and S were higher in leaves, and in pseudobulbs P, K, Ca, Mg, and S were higher. The results showed that there are positive effects on plant growth when FIW and LPS are used, while higher concentrations of nutrients in leaves, pseudobulbs and mainly in roots are observed when using SPS

Reproductive performance of hair sheep under different body conditions and feeding levels

O objetivo deste trabalho foi avaliar o efeito da interação entre nível de alimentação (FL) e escore de condição corporal (BCS) sobre os parâmetros reprodutivos de ovelhas de pelo Pelibuey (Ovis aries). As unidades experimentais (64 ovelhas) foram distribuídas aleatoriamente a um dos quatro tratamentos: baixo nível de alimentação e baixo escore de condição corporal; alto nível de alimentação e baixo escore nas condições corporais; baixo nível de alimentação e alto escore nas condições corporais; e alto nível de alimentação e alto escore nas condições corporais. O efeito do escore de condição corporal de ovelhas foi significativo sobre as taxas de prenhez e parto. O efeito do nível de alimentação foi significativo sobre as taxas de ovulação, retorno do estro, prenhez e prolificidade. O efeito da interação entre escore de condição corporal e nível de alimentação foi significativo sobre as taxas de ovulação, retorno do estro, prenhez, parto e prolificidade. A função reprodutiva é mais sensível aos melhores efeitos nutricionais em ovelhas com baixo escore de condição corporal.The objective of this work was to evaluate the effect of the interaction between feeding level (FL) and body condition score (BCS) on the reproductive parameters of Pelibuey hair sheep (Ovis aries). The experimental units (64 ewes) were randomly assigned to one of four treatments: low feeding level and low body condition score; high feeding level and low body condition score; low feeding level and high body condition score; and high feeding level and high body condition score. The effect of sheep body condition score was significant on the pregnancy and lambing rates. The effect of feeding level was significant on the ovulation, estrus returning, pregnancy, and prolificacy rates. The interaction effect between BCS and FL was significant on the ovulation, estrus returning, pregnancy, lambing, and prolificacy rates. The reproductive function is more sensitive to the better nutrition effects in sheep with a low body condition score

Plant growth and early in vitro floral differentiation of vanilla (Vanilla planifolia Jacks. ex Andrews)

Objective: To induce in vitro flowering of vanilla (Vanilla planifolia) with different plant growth regulators (PGRs) using the double-layer technique. Design/methodology/approach: A layer of semi-solid Knudson C (KC) medium, added with 40 g L-1 sucrose, 15% coconut water (CW; v/v) and 7 g L-1 agar, was placed in 100 mL flasks. A liquid layer of the same composition without agar was placed on top. It was supplemented with different doses (mg L-1) of PGRs: 6-benzyladenine (BA) (7), thidiazuron (TDZ) (6), paclobutrazol (PBZ) (0.5) and gibberellic acid (AG3) (2). Plus two controls, C1: no PGRs + no CW; C2: no PGRs + CW. Vanilla shoots of 2 cm in length and with at least one axillary shoot were placed. They were incubated at a temperature of 26±2 °C day and 18 °C darkness, with light intensity of 55 µmol m-2 s-1 during 13 weeks. The number of shoots, leaves and roots was evaluated, as well as the length of shoots and fresh weight. Floral differentiation was evaluated at the tenth week by conventional microtechnique. Results: The number shoots and leaves and shoot length were significantly higher in C2. The number of roots increased with PBZ 0.5 mgL-1. C1 and C2 promoted higher fresh weight. Floral differentiation was observed with AG3 2 and PBZ 0.5 mg L-1 treatments. Limitations on study/implications: Further evaluation of other PGR doses and environmental conditions is required to achieve full floral differentiation of vanilla. Findings/conclusions: CW increased vegetative growth. AG3 and PBZ showed early floral differentiation in Vanilla planifolia, which is the first report of this phenomenon for the species.

Cost analysis of Agave potatorum Zucc, produced in vitro by direct organogenesis

Objective: Demonstrate the efficiency and profitability of Temporary Immersion Bioreactors compared to propagation in gelled media. Design/methodology/approach: Agave potatorum shoots used. They introduced to in vitro system and the multiplication rate and propagation times compared in productivity, an investment project carried out considering the depreciation of the equipment and without considering the construction of the property, this allowed evaluating the cost of production per plant for a goal of 500 thousand plantlets. Results: 3% contamination was obtained at the beginning of introducing the in vitro system, the multiplication rate in semi-solid used was 4 shoots per explant and 18 shoots per explant in Bioreactors, both at 30 days of incubation, and it was considered a 10 % loss due to handling. The production cost was US$0.16 (MNX$3.20) for gelled media and US$0.09 (MNX$1.80) for propagation in Temporary Immersion Bioreactors. The Internal Rate of Return (IRR) for gelled media was 2.33 and 3.75 for propagation with Bioreactors. Limitations on study/implications: Study does not contemplate the construction of the property, but it does contemplate the depreciation of the equipment Findings/conclusions: With the development of science and technology, the use of biotechnological tools is becoming more profitable every day, these technologies are already available to be transferred, and works like this one, where the profitability of said activity is demonstrated, show the possibility of that technology-based companies are generated.Objective: To demonstrate the efficiency and profitability of temporary immersion bioreactors compared to propagation in gelled media.Design/Methodology/Approach: Agave potatorum seedlings were introduced to the in vitro system in order to compare their productivity, multiplication rate, and propagation time. An investment project was carried out considering the equipment depreciation, but without considering the construction of the property. Based onthese premises, the cost of production per plant was evaluated with a goal of 500,000 seedlings in mind.Results: A 3% contamination was recorded when the in vitro system was first introduced. The semi-solid multiplication rate was 4 shoots per explant and 18 shoots per explant in bioreactors, both at 30 days of incubation. A 10% handling loss was taken into consideration. The production cost was US$0.16 (MNX$3.20) for gelled media and US$0.09 (MNX$1.80) for propagation in temporary immersion bioreactors. The Internal Rates of Return for gelled media and for propagation with bioreactors were 2.33 and 3.75, respectively.Study Limitations/Implications: The study does not take into consideration theconstruction of the property, although it does consider equipment depreciation.Findings/Conclusions: Thanks to scientifical and technological development, the use of biotechnological tools is becoming more profitable every day. These technologies are already available to be transferred and this kind of research demonstrates its profitability, highlighting the potential establishment of technology- based companies

Silicon increases seed weight and initial seedling growth of maize under non-stress conditions, and improves the index of velocity of germination under salt stress conditions

Salinity is one of the most critical factors affecting agriculture worldwide. The application of beneficial elements like silicon (Si) is one of the alternatives to mitigate its effects. In this research, we evaluated the effect of Si applied during seed imbibition on mitigating the negative effects caused by salinity during the germination and initial growth phases of maize (Zea mays L.) SB-308 seedlings. Seed pre-treatment during the imbibition was made with 0.0-, 1.5- and 3.0-mM Si. Afterwards, seeds that were imbibed were placed in plastic containers and treated with 0, 80, 160, and 240 mM NaCl. The evaluated concentrations of Si and NaCl gave rise to 12 treatments. Pre-treated seeds with 3 mM Si had an increase of weight after imbibition, 5.1% higher than the control. The treatments obtained from combining NaCl and Si levels did not affect the total and relative germination. The radicle length increased by 13.6% with 3 mM Si compared to the control. Conversely, it was lower with increasing salinity. These trends were observed in plant height. The interaction of the study factors produced an increase in the radicle length in the interval from 0 to 160 mM NaCl, when the Si dose was increased. However, there were no significant differences among equal levels of salinity without Si. It is concluded that Si increased the absorption of water during the imbibition and raised the index of velocity of germination under salinity, except in the dose 240 mM NaCl. Likewise, the pre-treatment of seeds with Si tends to increase radicle length under saline conditions

Endogenous Hormone Profile and Sugars Display Differential Distribution in Leaves and Pseudobulbs of Laelia anceps Plants Induced and Non-Induced to Flowering by Exogenous Gibberellic Acid

A profile of endogenous hormones and sugars in leaves and pseudobulbs of Laelia anceps subsp. anceps (Orchidaceae) plants induced and non-induced to flowering by the effect of different doses of exogenous gibberellic acid (GA3), considering the current and back growth structures (CGS and BGS), were investigated. A factorial experiment with five doses of GA3 and two growth structures was designed. Adult plants with undifferentiated vegetative buds were selected and sprayed with doses of 0, 400, 600, 800, and 1000 mg GA3 L−1. The main results showed a strong interaction between GA3 dose and growth structures, which promoted the highest kinetin (KIN) concentration in CGS. Exogenous GA3 increased endogenous GA3 in leaves and pseudobulbs induced (I-Leaf and I-PSB) and non-induced (NI-Leaf and NI-PSB) to flowering. For sugar concentration, the 400 mg L−1 GA3 dose promotes significant interaction with the CGS in NI-PSB. In general, the hormone profile revealed opposite balances of endogenous hormone concentrations for KIN, zeatin (ZEA), trans-zeatin (T-ZEA), indoleacetic acid (IAA), indole-3-butyric acid (IBA) and GA3, not only for growth structures but also for vegetative organs analyzed, depending on whether the plants were induced or not induced to flowering, with the highest concentration of endogenous hormones in pseudobulbs. Likewise, different sugar concentration balances were observed. These balances of both endogenous hormones and sugars are likely to be involved in the flowering of L. anceps

Riqueza de la familia Orchidaceae en un bosque mesófilo de montaña en Chocamán, Veracruz, México

Antecedentes y Objetivos: Existen fragmentos de bosque mesófilo de montaña (BMM) en el centro de Veracruz que no se han estudiado florísticamente. El objetivo de la presente investigación fue registrar la riqueza de orquídeas en un fragmento de este tipo de bosque en Chocamán, Veracruz. Métodos: Se hizo trabajo de recolección de ejemplares, así como revisión de colecciones científicas e información bibliográfica. Resultados clave: El listado incluyó 36 especies pertenecientes a 25 géneros. Epidendrum fue el género con mayor número de especies (7), seguido por Dichaea, Lycaste, Oncidium, Prosthechea y Stelis, con dos cada uno, el resto de los géneros estuvo representado por una. Cuatro especies son endémicas de México (Epidendrum longipetalum, Gongora galeata, Oncidium incurvum y Trichocentrum pachyphyllum), y dos están protegidas por la legislación mexicana (O. incurvum y Stanhopea oculata). Epidendrum magnoliae y Epidendrum cf. radioferens son nuevos registros para la flora de Veracruz. Conclusiones: La orquideoflora aquí estudiada enfrenta problemas debido al cambio de uso de suelo y la extracción ilegal para comercio, por lo que urgen medidas para su conservación.Background and Aims: Some fragments of cloud forest (CF) in central Veracruz have not been studied floristically. The aim of the present investigation was to record the richness of orchids in a fragment of this type of forest in Chocamán, Veracruz. Methods: Specimens were collected and scientific collections and bibliographic information were revised. Key results: The list included 36 species, belonging to 25 genera. Epidendrum was the genus with more species (7), followed by Dichaea, Lycaste, Oncidium, Prosthechea and Stelis, with two each one, and all other genera were represented by one species. Four species are endemic to Mexico (Epidendrum longipetalum, Gongora galeata, Oncidium incurvum and Trichocentrum pachyphyllum); and two are protected by the Mexican legislation (O. incurvum and Stanhopea oculata). Epidendrum magnoliae and Epidendrum cf. radioferens are new records for the Veracruz flora. Conclusions: The orchid flora studied here faces problems because of the land-use change and illegal extraction for trade, thus conservation measures are urgent

Effect of amaranth residues (Amaranthus hypochondriacus L.) on weed control and yield or radish, onion and carrot

Studies were conducted to evaluate the effect of dry residue of amaranth (Amaranthus hypochondriacus L. var. Azteca) stem on weed growth and yield of radish (Raphanus sativus L. var. Champion), onion (Allium cepa L. var. Cambray), and carrot (Daucus carota L. var. Nantes), in order to determine the inhibitory effect of amaranth. The treatments were established under field conditions: 1) aqueous extract (AE); 2) soil-incorporated residue (S-IR); 3) surface-applied residue (S-AR); 4) unaltered soil control (U-S/C); 5) soil-incorporated control (S-I/C). The soil type at the study site was loamy-sand, with bulk density 1.47 m�3, containing 2.1% organic matter. The species with the largest number of plants and highest dry weight in the three vegetables were Simsia amplexicaulis (Cav.) Pers., and a group of Gramineae grasses. Weed reduction was observed with treatments S-AR and S-IR related to the respective controls (U-S/C and S-I/C). Generally, decrease in plant number and dry weight in both treatments varied from 60% to 97% during the vegetable cycle. Radish yield decreased significantly with S-AR and S-IR; whereas that of onion and carrot increased significantly with S-AR. The results indicate that amaranth residue, incorporated or surface applied may control some weeds in radish, onion, and carrot. The surface-applied residue has potential to increase the yield of onion and carrot. However, it is necessary to find optimal residue management conditions for its application in the field to avoid reduction in yield of sensitive crops like radish, and/or when the residue is incorporated.El estudio se realizó para evaluar el efecto del residuo seco del tallo de amaranto (Amaranthus hypochondriacus L. var. Azteca) en el crecimiento de maleza y el rendimiento de rábano (Raphanus sativus L. var. Champion), cebolla (Allium cepa L. var. Cambray) y zanahoria (Daucus carota L. var. Nantes), para determinar el efecto inhibitorio del amaranto. Los tratamientos se establecieron en condiciones de campo: 1) extracto acuoso (EA); 2) residuo incorporado en el suelo (RI); 3) aplicación superficial del residuo (RS); 4) testigo sin alteración del suelo (TE-S/AS); 5) testigo con incorporación del suelo (TE-C/IS). El tipo de suelo en el sitio de estudio fue arenoso-migajoso, con densidad aparente de 1,47 m�3 y 2,1% de materia orgánica. Las especies con mayor número de plantas y mayor peso seco en las tres hortalizas fueron Simsia amplexicaulis (Cav.) Pers., y un grupo de gramíneas. Se observó disminución de maleza con los tratamientos RS y RI en relación con los testigos respectivos (TE-S/AS y TE-C/IS). De manera general, la disminución del número de plantas y peso seco en ambos tratamientos varió de 60% a 97%, durante el ciclo de las hortalizas. El rendimiento de rábano disminuyó significativamente con RS y RI; el rendimiento de cebolla y zanahoria aumentó significativamente con RS. Los resultados indican que el residuo de amaranto, incorporado o aplicado superficialmente, puede controlar maleza en rábano, cebolla y zanahoria. El residuo aplicado superficialmente tiene potencial para incrementar el rendimiento de cebolla y zanahoria, sin embargo, es necesario encontrar condiciones óptimas del manejo del residuo para su aplicación en campo y para evitar que disminuya el rendimiento de cultivos sensibles como el de rábano y/o cuando el residuo es incorporado