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The range of floral colors is determined by the type of plant pigment accumulated by the plant. Anthocyanins are the most common flavonoid pigments in angiosperms; they provide a wide range of visible colors from redmagenta to blue-purple, products of cyanidin and delphinidin biosynthesis, respectively. For the floriculture industry, floral color is one of the most important ornamental characteristics for the development of new commercial varieties; however, most plant species are restricted to a certain color spectrum, limited by their own genetics. In fact, many ornamental crops lack bluish varieties due to the lack of activity of essential biosynthetic enzymes for the accumulation of delphinidin. An example is the poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch), the ornamental plant symbol of Christmas and native to Mexico. Its popularity is the result of the variety of colors displayed by its bracts, a kind of modified leaves that accumulate reddish pigments based mainly on cyanidin and, to a lesser extent, on pelargonidin. The commercial success of this plant lies in the development of new varieties and, although consumers like the typical red color, they are also looking for poinsettias with new and innovative colors. Previous research has demonstrated the possibility of manipulating flower color through metabolic engineering of the anthocyanin biosynthesis pathway and plant tissue culture in different ornamental plant species. For example, transgenic cultivars of flowers such as roses, carnations or chrysanthemums owe their attractive bluish colors to a high and exclusive accumulation of delphinidin. Here, we discuss the possibilities of genetic engineering of the anthocyanin biosynthetic pathway in E. pulcherrima through the introduction of one or more foreign delphinidin biosynthetic genes under the transcriptional control of a pathway-specific promoter, and the genome editing possibilities as an alternative tool to modify the color of the bracts. In addition, some other approaches such as the appropriate selection of the cultivars that presented the most suitable intracellular conditions to accumulate delphinidin, as well as the incorporation of genes encoding anthocyanin-modifying enzymes or transcription factors to favor the bluish pigmentation of the flowers are also revised. [ABSTRACT FROM AUTHOR]

The irrational exploitation of native species of arid and semi-arid areas of Mexico, in particular the huizache (Vachellia spp.), created the need to carry out research work that contributes to the reforestation of these areas. Vachellia spp. pods have been characterized by their nutritional value and use in ruminants, in addition to the fact that generally the seeds present germination problems under natural conditions, due to their hard and impermeable cover that prevents the passage of water. This is a problem that can be solved through the use of micropropagation. This technology has made it possible to obtain thousands of disease-free seedlings with characteristics identical to the plant that gave them origin, and so far there is no extensive research on the subject that includes diversity of species of the genus Vachellia L., some of the few examples are the case of the efficient induction of callus of the species Vachellia macracantha, induction of shoots and multiplication of Acacia auriculiformis, in vitro propagation of Acacia chundra and the hybrid Acacia mangium and A. mangium x A. auriculiformis hybrids, among other methodologies. Scarification methods (physical, chemical and mechanical) interrupt the dormancy of the seeds and by placing them in a suitable culture medium (macro and micronutrients, sucrose, growth regulators), large productions have been obtained in a short time. The aim of this Bibliographic Review was to compile the most relevant results on plant tissue culture in species of the genus Vachellia L. [ABSTRACT FROM AUTHOR]

Vanilla is the orchid of greatest economic interest to the world since the spice of the same name is obtained from it. Vanillin is obtained from its ripened pod, this compound is highly recognized and demanded by the gastronomic, pharmaceutical, and cosmetic industries for the sweet aroma and flavor it emanates. The objective of this work was to carry out a literature review to put into perspective the reader about the sustainability strategies in the vanilla industry in Mexico, as well as the innovations of propagation and in vitro conservation of Vanilla planifolia germplasm. Despite being originally from Mexico, this country ranks third in world production, preceding Madagascar, and Indonesia. This compilation of studies presents biotechnological techniques to increase vanilla production, as well as alternatives that can reduce the negative effects caused by the low genetic accumulation in this species, such as plant tissue culture, use of molecular markers for the study of somaclonal variation, asymbiotic seed germination under in vitro conditions. These techniques together with agroindustrial strategies can represent a sustainable alternative for vanilla production. In this article, strategies are suggested that allow those interested in vanilla production to make appropriate decisions, however, it is necessary to develop multidisciplinary studies that allow a global approach to the phenomena involved in the production and use of vanilla, as well as the resolution of the problems that this process faces. [ABSTRACT FROM AUTHOR]

Pinus pseudostrobus Lindl. is a species endemic to Mexico and is widely used in reforestation programmes, as it is highly adapted to poor, shallow, limestone soils and has high commercial importance. However, it is necessary to preserve this genetic material since it is in trouble due to high rates of deforestation, land use change, and forest fires, so it is necessary to have effective strategies to obtain good quality seedlings. Due to the properties of LED (light emitting diode) lamps used for illumination in the production of in vitro plants, the effects of two different lighting systems (LED and fluorescent) on an in vitro culture were analysed for the morphological characteristics of the growth and photosynthetic pigment content in P. pseudostrobus seedlings. The length and root size of the seedlings were affected by the type of illumination, where a red LED light was the most effective at 30 days of evaluation. However, a blue LED light was equally effective as a red LED light at 60 days of seedling development. On the other hand, the fluorescent light was better in terms of the number of needles in the first stage, but we found the blue LED light to be better in the second stage. For the photosynthetic pigment content, the highest values were found with the blue LED light. The results showed that the LED lighting system favours the growth, development, and photosynthetic pigment content of the species under study. [ABSTRACT FROM AUTHOR]

Tillandsia viridiflora (Beer) Baker is an epiphytic bromeliad endemic to Mexico, and the destruction of its habitat and illegal trade have led to its inclusion in the list of endangered species in NOM-059-SEMARNAT-2010. For its commercial use as an ornamental plant, a massive propagation system is required. In vitro plant tissue culture techniques are an option for producing large numbers of plants. The objectives of this study were to determine the optimal conditions to regenerate plants in vitro by direct organogenesis and acclimatize them. Organogenesis was evaluated in Murashige-Skoog (MS) medium with 6-benzylaminopurine (BAP, 0.0 and 8.8 µM) and naphthaleneacetic acid (NAA, 0.0 and 2.1 µM) from in vitro seedlings germinated in MS medium with 50% of the salt concentration. Shoot groups were placed in MS medium with gibberellic acid (GA3, 0 and 5.77 µM) to promote elongation. Shoot rooting was evaluated in MS medium with 50% of the salt concentration added with NAA (0.00 and 2.15 µM) and indole-3-butyric acid (IBA) (0.00 and 2.15 µM). During acclimatization, we evaluated two plant heights and two types of substrates: peat + perlite (1:1) and pine bark (Pinus). We established a completely randomized design and the data obtained were analyzed with ANOVA; the Tukey test was used for the comparison of means. Germination was 82% in five weeks. In the organogenesis, 10.4 shoots were induced per explant with 6.65 µM of BAP and 0.5 µM of NAA, and the multiplication resulted in 13 shoots with 4.4 µM of BAP and 0.5 µM of NAA, both cases in 12 weeks. The largest elongation (1.5 cm) of the shoots occurred by adding 5.7 µM of gibberellic acid; and the highest number of roots (2.4 roots per plant) resulted from adding 1.0 µM NAA. In acclimatization, survival was 100% with 4.5 and 6.5 cm plants planted in peat+perlite and pine bark [ABSTRACT FROM AUTHOR]

Randia echinocarpa, an endemic plant to Northwest Mexico, is used as food and in traditional medicine, and several of its biological activities have been demonstrated (antioxidant, antimutagenic, antidiabetic, and immunomodulatory). Plant tissue culture is a safe and scalable system for plant propagation and production of bioactive compounds. Therefore, this study aims to establish protocols for seed germination and callus culture of R. echinocarpa and to evaluate the antioxidant activity of methanol extracts (ME) of plantlets and calli via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods. Seeds were cultured in media with different concentrations of Murashige and Skoog (MS) salts and sucrose, and a higher germination rate and plantlet growth was observed in half-strength MS medium with 15 g L−1 of sucrose. Calli were obtained from cotyledon and hypocotyl explants cultured in MS media with different concentrations of benzyl aminopurine (BAP) and indole-3-acetic acid (IAA). All treatments induced callus formation in 100% of explants; however, the medium containing 1 mg L−1 BAP + 1 mg L−1 IAA was selected because it produced calli with higher biomass and friable texture. The ME of cotyledons showed the highest antioxidant activity values (μmol Trolox per 100 g dry weight) in DPPH (345.5) and ABTS (1166.4) assays, whereas the ME of calli from hypocotyls showed a higher antioxidant activity than the ME of calli from cotyledons in both antioxidant assays. The tissue culture protocols established here will be useful for R. echinocarpa germplasm conservation and propagation, as well as for the production of bioactive compounds. [ABSTRACT FROM AUTHOR]

Guignardia bidwellii (anamorph Phyllosticta ampelicida) is the etiological agent of grape black rot, a disease of economic importance in Europe and a quarantine pest for Mexico. The identification of the anamorphic state by morphological characteristics is complicated, due to the similarity among species of the same genus, for example with the cosmopolitan endophyte G. endophyllicola (P. capitalensis), therefore it is necessary to have quick and specific diagnostic tools. For this purpose, a molecular marker based on single nucleotide polymorphisms (SNP) in the ITS region of the rDNA was developed, where the Bidwell and Ampel2 primers were designed. The PCR amplification generates a fragment of 173 bp, specific to G. bidwellii f. euvitis. The validation of the method showed that there is no cross amplification with closely related phytopathogenic fungi or with the genome of grapevine. The technique was sensitive to detect up to 30 pg μL-1 of DNA from monosporic cultures and in mixture of plant tissue. This diagnostic procedure is presented as a fast and specific option for the monitoring, and detection of G. bidwellii f. euvitis in support of prevention, management, quarantine and eradication strategies of the disease. [ABSTRACT FROM AUTHOR]