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Exploitation of the "ocotillo" tree (Fouquieria splendens Engelm) to produce ocotillol/ocotillone (o/o) in Northern Mexico hasn't been explored to this date. In the present work, isolation of ocotillol/ocotillone was performed through a batch reactor, which allowed the elimination of alcohol and phenols present in the ocote plant, yielding only resins and waxes from the ocote trunks. The ocotillol/ocotillone was extracted from the remaining resin on the ocote logs by solvent extraction in a batch reactor, to be crystallized after its extraction using a rotary evaporator. FTIR, and NMR analysis exhibited the characteristic ginsenoside bands, while the UV-vis spectrum of ocotillol/ocotillone depicted an absorption band belonging to the O-H bonds, indicating that the group is anchored to the ginsenoside structure and not due to a water signal. Lastly, the thermogravimetric analysis described a common behavior among other ginsenosides. Production of ocotillo/ocotillone has an energy consumption of 3624 kWh/gr. With a cost of $0.478 USD in laboratory equipment, which translates as a plausible sustainable production of ocotillol/ocotillone.

In desert regions, species have adapted physiologically and behaviorally to the extreme conditions of their environment, such as a lack of water and extreme temperatures. This is the case of the mule deer (Odocoileus hemionus) a species which many aspects of its relationship between behavioral ecology and habitat characteristics are unknown. The objectives of this study were: 1) to characterize the daily activity pattern of female mule deer in relationship to three behavioral patterns: resting, feeding and moving, and 2) assess the relationship between these behavioral patterns and the characteristics of the habitat. This study was conducted in the Chihuahuan Desert, where six females of mule deer were monitored using VHF radiotelemetry between 2012 and 2014. We distinguish the behavioral patterns by sensors in the collar and we quantified the number of beeps emitted per minute. Moreover, we described the daily pattern associated with these activities using Kernel density graphs and evaluated the effect of habitat variables on the frequency of resting and feeding behaviors applying a generalized linear model (GLM). We identified the location in which feeding and resting behaviors occurred, and the type of plant associations present and the percentage of area they occupied. We recorded locations over 328 days/deer. Female mule deer spent most of their time resting (63.41 %), followed by moving (21.26 %), and feeding (15.34 %). Deer movement and feeding behaviors were most frequent during the crepuscule. The temperature was the only variable that influenced resting and feeding behaviors (deviance = 4.7; d. f. = 1; P = 0.02). The estimated area used for resting was 10.35 km2, while the corresponding area for feeding was 6.45 km2, in which the plant association with dominance of Larrea tridentata, Opuntia rastrera and Fouquieria splendens was the most common. Considering the high temperatures prevailing on the region, resting most of the day likely helps deer to have an adequate thermoregulation. The time dedicated to feeding is less than the dedicated to other activities; deer may be spending more time moving than feeding due to the spatial distribution of suitable food patches, or to avoid predators. The mule deer occupy the same areas to feed and rest; however, feeding areas are smaller those used to rest, these areas have been identified in previous studies as those with the greatest use (core areas). In the plant association with greater occupation within the feeding zones, there are species reported as an essential for the deer diet; these areas are located at the foot of the hill, which gives the deer thermal protection.

Background: Secondary metabolites are important chemomarkers. However, as a system to confront biotic and abiotic stress, chemical composition can vary, improving the phenotypic plasticity of plants. We determined the potential of the foliar and floral phenolic composition, floral carotenoid contents to discriminate between two subspecies of Fouquieria splendens and assessed the effect of atypical environmental conditions on the chemical composition of a relict population of the subspecies splendens . Hypothesis: We hypothesized that chemical differences have arisen between the analyzed subspecies and in the relict population allowing the differentiation between them. Species studied: Fouquieria splendens subsp. splendens and Fouquieria splendens subsp. campanulata (Fouquieriaceae). Study site and years of study: Mezquital, Peñón Blanco, and San Juan del Río, Durango, México. March to August 2016. Methods: Foliar and floral extracts were analyzed by HPLC-DAD, UV-visible spectrophotometry, and FTIR-ATR. Multivariate analysis was used to assess the sample distinctiveness and to establish the relation between the chemical composition and environmental variables. Results: The chemical composition was highly conserved between the analyzed samples. Contrarily, an evident distinctiveness between phytochemical contents was observed. Soil parameters were the factors determining the particular quantitative phenolic profiles. Conclusions: The analyzed subspecies and populations showed similar chemical patterns; however, quantitative variations, determined by soil texture, electrical conductivity, organic matter, organic carbon, and contents of K, Ca, and Na, allowed to differentiate them. The important phenolic quantitative variation of the atypical population of F. splendens subsp. splendens suggests a relevant contribution of phenolic compounds to the adaptation to its relict condition.

Premise of the study The C3 desert shrub ocotillo (Fouquieria splendens) completely lacks xeromorphic leaves but is uncommonly both stem succulent and repetitively drought deciduous (documented to have produced many foliation-defoliation cycles during a growing season). Both adaptations conserve water in this xerophyte, but are the roles of succulence and deciduousness merely redundant? The observation that year-to-year reproductive effort was relatively consistent while vegetative growth was not offered a critical clue that, coupled with long-term precipitation data, helped answer this question. Methods At two sites in the Chihuahuan Desert in southern New Mexico, United States, 22 ocotillos were studied annually for more than two decades to explore the relationships among reproductive effort, vegetative stem growth, and patterns of precipitation. Key results Vegetative stem growth occurred in mid- to late summer (July-September), the season of maximum precipitation in the Chihuahuan Desert, and was significantly related to summer precipitation received in the year of growth. Reproductive effort occurred in early to late spring (April-June), which with winter account for minimum precipitation during the year, but was significantly related to summer precipitation received in the previous year, suggesting the importance of stem succulence and stored water. Conclusions While highly variable summer precipitation was responsible for enormous fluctuations in annual ocotillo stem growth, stem succulence insulated reproductive effort from such immense variability. Stem-stored water allowed the production of flowers and fruits to proceed relatively consistently during the driest years and during the driest time of year in the Chihuahuan Desert.

Fouquieria splendens is a stem-succulent native to the Chihuahuan, Mojave, and Sonoran Deserts that spans Mexico and the American Southwest. It is well-known for its variable morphology, the underlying reason for which remains incompletely understood. Here, we attempt to quantify the effect of topographic and interspecific factors on F. splendens morphology and distribution. To this end, we measured 27 ocotillos located in the Organ Pipe Cactus National Monument within the Sonoran Desert during June of 2019. We also quantified the spatial distribution of interspecific neighbors relative to F. splendens within two topographically different sites: a bajada gradient and a plain. Using ocotillo morphology, the distances to the nearest neighbors of ocotillos, and hydrographic data extracted from the National Hydrography Dataset, we demonstrate 1) the effect of major interspecific neighbors, i.e. shrubs and cacti, on ocotillo morphology; 2) the effect of elevation on intraspecific spacing as individuals compete for limited space; and 3) a trade-off between height and number of branches. This places F. splendens morphology in its larger environmental and ecological context, highlighting the importance of individual traits and associated trade-offs among traits affected by topography and interspecific neighbors. By examining the ocotillo in a multi-species community and diverse landscape, this study provides empirical insight into a wider range of factors contributing to the variation in F. splendens morphology and spacing.

We discuss the radiation and dispersal of Fouquieria, the sole genus of Fouquieriaceae, that includes eleven species, all endemic to the warm deserts and dry subtropical regions of North America. Two sister species occur in the Chihuahuan Desert, the broadly distributed Fouquieria splendens and the microendemic gypsophilic F. shrevei from a few localities in Coahuila, Mexico. Both species coexist in the valleys and mountain ranges west and around Cuatro Cienegas, but in the Cuatro Cienegas valley, despite wide availability of gypsum soils, only F. splendens is found. Fouquieriaceae represents an ancient lineage that diverged from Polemoniaceae during late Cretaceous, but speciation of Fouquieria species occurred during the Mio-Pliocene mainly by vicariance, associated with Neogene orogenesis underlying the early development of regional deserts. The clade formed by F. shrevei and F. splendens diverged from F. macdougalii by a vicariant event that took place during the early Pliocene. However, opposed to the rest of the species, the divergence between F. shrevei and F. splendens, which grow sympatrically, could have occurred by ecological speciation associated with the colonization of gypsum soils by F. shrevei. The patchiness of gypsum deposits in Coahuila has resulted in selection, intense genetic drift, and reduced gene flow among F. shrevei populations.

Introduction: Fouquieria splendens commonly named "ocotillo", is a native plant from Mexico, used in folk medicine against different illnesses. However, scientific evidence about its biological activities is limited. The objective of this study is to determine phenolic composition, antioxidant and antiproliferative effect of F. splendens. Methods: Amethanolic extract from F. splendens leaves extract (F. splendens extract) was obtained and fractioned by liquid-liquid partition, obtaining hexane, ethyl acetate, and residual fractions. Phenolic compounds were determined by the Folin Ciocalteu method, and the phenolic profile was assessed by UPLC-DAD. Antioxidant activity was determined by DPPH, TEAC, ORAC, and FRAP assays. Antiproliferative activity was performed by MTT assay against C33-A and HeLa cell lines. Results: The ethyl acetate fraction exhibited the highest (p Conclusion: The results showed a promissory biological potential of F. splendens, associated with phenolic compounds, besides the first report on the identification of some phenolic compounds in this plant.

Arid biomes are particularly prominent in the Neotropics providing some of its most emblematic landscapes and a substantial part of its species diversity. To understand some of the evolutionary processes underlying the speciation of lineages in the Mexican Deserts, the diversification of Fouquieria is investigated, which includes eleven species, all endemic to the warm deserts and dry subtropical regions of North America. Using a phylogeny from plastid DNA sequences with samples of individuals from populations of all the species recognized in Fouquieria, we estimate divergence times, test for temporal diversification heterogeneity, test for geographical structure, and conduct ancestral area reconstruction. Fouquieria is an ancient lineage that diverged from Polemoniaceae ca. 75.54 Ma. A Mio-Pliocene diversification of Fouquieria with vicariance, associated with Neogene orogenesis underlying the early development of regional deserts is strongly supported. Test for temporal diversification heterogeneity indicates that during its evolutionary history, Fouquieria had a drastic diversification rate shift at ca.12.72 Ma, agreeing with hypotheses that some of the lineages in North American deserts diversified as early as the late Miocene to Pliocene, and not during the Pleistocene. Long-term diversification dynamics analyses suggest that extinction also played a significant role in Fouquieria’s evolution, with a very high rate at the onset of the process. From the late Miocene onwards, Fouquieria underwent substantial diversification change, involving high speciation decreasing to the present and negligible extinction, which is congruent with its scant fossil record during this period. Geographic phylogenetic structure and the pattern of most sister species inhabiting different desert nucleus support that isolation by distance could be the main driver of speciation.

Perennial plants of desert regions can be categorized as short-, moderate-, or long-lived. For long-lived species, the typical range of adult life spans is often poorly known, as well as how reproductive effort is apportioned across years. Ocotillo (Fouquieria splendens), a large shrub of the Chihuahuan and Sonoran Deserts, is considered long-lived and flowers spectacularly, but few data exist on these aspects of its life history. In Big Bend National Park, Texas, I marked 140 mature ocotillos in 1986–1988 at 8 sites and measured inflorescence production. In 1990, 2003, 2018, and 2019, I again measured flower output and determined fates of 95 plants which could be relocated, 64% of which survived the 33-year interval. Smaller plants survived better than larger ones. With an annual survival probability of 0.986, the median plant entering adulthood was projected to live 51 more years. All plants flowered in each study year unless buds froze; means ranged from 8 to 60 inflorescences (approximately 680–5200 flowers) per plant per site. Most survivors made more inflorescences in 2018–19 than 29–33 years earlier. Thus, an average ocotillo produces large crops of flowers for approximately 50 years, an appropriate strategy if seedlings rarely survive.

Core activity areas are the most important sites within an animal’s home range as they contain the greatest density of critical resources. Because these areas are small and intensively used, they can affect the total distances covered by animals searching for resources. Our objective was to document which habitat variables affect core area selection by female mule deer (Odocoileus hemionus) in an arid environment, and to learn which variables affect their displacement within these areas. Using radiotelemetry, from 2012 to 2014 we monitored seven female mule deer. We estimated their core areas, and with this information we identified and classified the location records as inside or outside of the core area. For each record, we also recorded variables related to time (month, time of day), environmental conditions (temperature, relative humidity), and habitat characteristics (plant association, distance to the nearest water body, slope), and used them to predict the presence of the deer in the core area using Classification and Regression Trees (CART). The same variables were analyzed using a GLM to determine which factors explain variations in displacement distance. The most important variable in core area selection was the distance to the nearest body of water (

Ocotillo ( Fouquieria splendens ), an iconic plant of the Chihuahuan and Sonoran Deserts in the United States and Mexico, has the reputation of being a long-lived shrub capable of attaining ages of two centuries or more. However, evidence of this potential longevity is lacking given that 104 years has been the oldest confirmed age recorded. The recent finding that growth rings can be accurately counted in the woody trunks of ocotillo has provided an opportunity to determine whether these rings merely identify the punctuated, sporadic growth common in this plant, or whether they actually represent ocotillo age. In seedlings studied for 22 years in southern New Mexico, growth rings enumerated in their trunks equaled total plant age. This apparent equivalence between growth rings and age was in spite of the fact that no measurable stem elongation occurred in up to nine of the 22 years of study in an ocotillo that also had no stem elongation in four consecutive years. A mature ocotillo harvested at this site that had 107 growth rings further supports the reality of a century-plus lifespan for ocotillo. The puzzle of longevity in this distinctive shrub of the desert Southwest can now be addressed with future research, but the possibilities go beyond the determination of maximum lifespan. These possibilities include dendrochronological studies that may well allow important analyses of patterns related to climate change in deserts where biological monitors of change are not always present or obvious.

Las reacciones químicas comunes de todos los seres vivos implican a los metabólitos primarios, sin embargo, otros compuestos se derivan de los anteriores, los metabólitos secundarios. Los usos de Fouquieria splendens Engelm (ocotillo) llegan a ser variados, sin embargo, no se conocen los metabólitos secundarios responsables de dicha actividad, por lo que el primer objetivo fue determinar la actividad biológica de los extractos y fracciones. El material vegetal se colectó en el municipio de Aldama en el Estado de Chihuahua, el cual se secó y se molió, para la obtención de extractos acuosos y orgánicos, la separación de estos se realizó por medio de cromatografía líquida al vacío (VLC), cromatografía de capa fina (TLC); se realizaron estudios biodirigidos de dichos extractos y de las fracciones obtenidas contra insectos Myzus persicae, Rhopalosiphum padi, Spodoptera littoralis. El extracto metanólico de hoja presento un menor índice de asentamiento de M. persicae, menor índice de asentamiento y efecto antialimentario de R. padi, los extractos crudos no presentaron actividad antialimentaria contra S. littoralis. Las fracciones 9 y 13 (VLC) produjeron efecto antialimentario contra M. persicae, la fracción 7 (VLC) produjo efecto antialimentario y menor índice de asentamiento de M. persicae.

The plant locally known as ocotillo, Fouquieria splendens (Fouquieriaceae) is a shrub distributed in arid zones of Mexico and southwestern United States. In Mapimi Biosphere Reserve, Durango, it has not leaves for most of the year; these emerge after the first rain. Inflorescences emerge in March, being bright red and lasting only a month. These inflorescences are highly sought after by animals, including insects, birds and the mule deer (Odocoileus hemionus). The objectives of this study were: 1) quantify the inflorescences produced by each plant (during March), 2) estimate inflorescence availability for mule deer, and 3) quantify its contribution in biomass (fresh weight) and nutrient content. This will contribute to understand why deer consume these flowers in the dry season. In March 2012 a field sampling was carried out in the Mapimi Biosphere Reserve, to measure the characteristics of each individual plant, quantify the number of inflorescences produced, the number available for mule deer, and the nutrients they contribute. The nearest-neighbor method was used, measuring 30 ocotillo individuals in nine sites. Inflorescences were collected from different plants to estimate fresh weight and determine nutrient content by proximal chemical analysis. A total of 270 ocotillo plants were sampled. There was a positive correlation between plant diameter and number of both branches and inflorescences. An average of 30 inflorescences was observed, and their availability for deer was 42 % (3,306/7,951) of the total. The average weight of 74 inflorescences collected was 74.8 ± 20.4 g; each plant produced up to 3 kg. These contain high levels of protein (15 % dry basis), carbohydrate (67 %), and 3,085.98 kcal/kg of metabolizable energy; 85 % are digestible nutrients. The mule deer selects plants with high nutritional values that are available in critical seasons such as the dry season. To note, ocotillo flowers emerge when there is food shortage (dry season), and are consumed by deer. A positive correlation was found between number of branches, plant diameter and total number of inflorescences (and its availability). Ocotillo flowers represent an important nutritional resource for deer, because inflorescences have high protein and sugar levels, in addition to having digestible nutrients and that each plant produces around 1.5 kg of inflorescences available for deer in the dry season.

I studied growth and longevity of the C3 drought-deciduous shrub Fouquieria splendens (ocotillo) growing in the Chihuahuan Desert in New Mexico for 22 years through the analysis of rings produced in trunks and stems. Ocotillos studied had 1–64 stems longer than 40 cm, maximum stem lengths of 50–370 cm, and 21–107 growth rings in their trunks. Although trunk rings were positively related to stem rings immediately above the trunks, the base of the largest stems immediately above the trunks had up to 58% fewer rings than the trunks. One growth ring was added to every existing stem segment only in years when a new terminal segment was produced on that stem, and adjacent segments produced in the same year had only one growth ring each. While the 107 growth rings in the trunk of the presumably oldest ocotillo in this study closely match the oldest ocotillo age derived from direct evidence (104 years), the challenge now is to discover whether ocotillo trunk rings really are annual rings.

A continuum of juvenile to reproductively mature ocotillos (Fouquieria splendens) was studied to determine changes in dry mass partitioning and production in relation to plant morphology. Gas exchange and productivity for 1‐yr‐old plants were also studied under controlled temperatures typical of winter, spring, and summer, which are the seasons that receive rain in the Sonoran Desert. Root:shoot ratios of young ocotillos decreased with total plant dry mass, suggesting smaller plants need relatively more soil resources than do larger plants. Young ocotillos had a greater scaling exponent for plant height versus total plant dry mass than for basal diameter versus total plant dry mass, which is indicative of their shoot morphology. Average rooting depth increased only 0.05 m per meter increase in plant height, reflecting the dependence of ocotillos on shallow soil water and explaining their rapid phenological responses to light rainfall events. Young ocotillos experienced maximal CO2 uptake when exposed to s...

Paradoxically low nitrogen resorption efficiency in the drought-deciduous desert shrub Fouquieria splendens Engelm (ocotillo) triggered tests of the hypotheses that resorption is often low in this species and that resorption is influenced by zinc. Resorption efficiency and proficiency were measured in 1989 and 1994 at two sites in the Chihuahuan Desert in plants to which zinc, or zinc and nitrogen were added. Resorption of nitrogen, phosphorus, and zinc in unfertilized plants varied temporally and spatially, but was both efficient (66%, 49%, and 40%, respectively) and proficient (0.55%, 0.09%, and 9.4 μg g−1, respectively) as determined by comparison to worldwide resorption patterns in a wide variety of other species. Applications of zinc had no significant effect on the resorption of nitrogen and phosphorus, but did influence the resorption of zinc. Resorption of zinc was significantly less efficient in zinc-treated plants than controls at only one of the two sites in one of the 2 years, yet resorption of zinc was significantly less proficient in zinc-treated plants than controls in both years and at both sites. This pattern of zinc resorption adds insight into the continuing debate regarding the relationship between fertility and resorption because the data used to fuel the debate have almost exclusively described macronutrients, not trace metals. The high variability in resorption among individuals, sites, and years observed for F. splendens may well be an attribute of many desert-dwelling, drought-deciduous plants. When senescence is controlled primarily by water availability rather than photoperiod, especially in a landscape characterized by unpredictable amounts and timing of precipitation, high variability in associated processes such as resorption may be inevitable.

Fouquieria splendens ssp. breviflora is a species of the family Fouquieriaceae, growing in arid zones of Mexico, between 700 and 2100 m above sea level (a.s.l). This species characteristically forms leaf buds under conditions of adequate water supply. The physiological response of this species was studied under varying conditions of irrigation in soil and water, using stems collected during two seasons: dry and rainy; evaluating the foliar material produced the quantity of free proline and total protein and anatomical foliar changes in the water conduction systems. This species displayed distinctive adaptive mechanisms involving the development of foliar fascicles, differentiation of vessels with formation of tracheal elements, and, metabolically, a high proline and total protein content in the stems of the dry season, showing that the responses observed in F. splendens spp. breviflora are adaptive physiological responses that take place simultaneously, being evidence of the first mechanisms of response to water-stress conditions. Thus, this species is regarded as a poikilohydric plant, as it is capable of the regulation of its metabolism during bud development when flooding events occur in the species' habitat after a prolonged dry and desiccation period.

The decomposition of leaf litter for five dominant plant species of a desert scrub in Baja California Sur, Mexico was investigated. We designed a factorial decomposition experiment using decomposition bags and the collected leaf-litter from Prosopis articulata, Jatropha cinerea, J. cuneata, Cyrtocarpa edulis, and Fouquieria diguetti. Factors, such as radiation exposure, rainfall, and the size of litter-consuming organisms were considered. The rates of litter decomposition were calculated for these plant species and the environmental conditions by using single exponential models. The initial concentration of nutrients (C, N, P, K, and Ca) and crude-fiber content of the leaf litter were determined. Our results show that the environmental heterogeneity generated by different conditions of radiation exposure and short-term rainfall patterns are the most relevant factors affecting decomposition processes in this Sonoran desert community. A species-specific pattern was observed in decay rates and mass-loss patterns. Decomposition rates varied from 0.0027 to 0.0201 depending on the species and exposure to different ecological conditions. The decay rates were higher under bare-soil conditions and during a wet year than under the shade provided by the canopy of nurse trees and during a dry year. The leaf litter of J. cuneata reincorporated to the soil more rapidly than that of P. articulata and C. edulis. Termites were the more important macroarthropods associated with litter decomposition, and their harvest distribution was independent of the resources distribution. The ecological significance of these results is discussed considering the extreme climatic conditions prevailing in this region.

Dead and downed ocotillos (Fouquieria splendens) are common in the Colorado Desert of southern California and pose a question concerning the life-span of adult plants that have been reported to be long-lived: if ocotillo is long-lived, decay rates must be very slow. Our study focused on decomposition and disintegration of above-ground ocotillo wood over 14 years to obtain a rate of change in dead mass. Disintegration rate was used in a new application of life-cycle graph analysis to calculate persistence time of carcasses, which in turn was used to estimate adult survival rates. We conclude that previous estimates of life spans may be too conservative and half-life of adult shrubs is over 200 years. Our approach to estimating adult survival from decay rates provides an independent test of survival transitions based on live plants for some species and so is an additional tool for developing life cycle models.

The capacity of individual branches to store water and fix carbon can have profound effects on inflorescence size and architecture, thus on floral display, pollination, and fecundity. Mixed regression was used to investigate the relation between branch length, a proxy for plant resources, and floral display of Fouquieria splendens (ocotillo), a woody, candelabraform shrub of wide distribution in arid North America. Long branches produced three times as many flowers as short branches, regardless of overall plant size. Long branches also had more complex panicles with more cymes and cyme types than short branches; thus, branch length also influenced inflorescence architecture. Within panicles, increasing the number of cymes by one unit added about two flowers, whereas increasing the number of cyme types by one unit added about 21 flowers. Because flower production is mediated by branch length, and because most plants have branches of various lengths, the floral display of individual plants necessarily encompasses a wide range of inflorescence size and structure.

The floral biology of Fouquieria splendens (Fouquieriaceae), a drought-deciduous shrub with wandlike branches, was studied in the northern Sonoran Desert. Two different measures of plant size, number of branches long enough to flower (>1 m in length) and actual number of reproductive branches, were used to examine the effect of plant size on reproductive output and floral display. Number of flowers and fruits increased with either measure of plant size. Annual flower production ranged from 190 to 6465 per plant and averaged 2553. Annual fruit production ranged from 9 to 1760 per plant and averaged 390. Because some branches long enough to flower did not do so, number of reproductive branches was a stronger predictor of flower production than number of branches > 1 m long. Inflorescence size (mean number of flowers per panicle) was not significantly related to plant size (number of flowering branches) in 2002 or 2003; in fact, the range in inflorescence size on certain individual plants was about ...

Los cultivos de células vegetales son sistemas experimentales homogéneos altamente controlables que permiten el estudio de adaptaciones bajo condiciones de estrés hídrico, sin la interferencia de los diferentes tejidos y estados del desarrollo vegetal. Una aproximación para comprender esas adaptaciones, es la aparición de proteínas inducidas, resultado de la alteración en la expresión génica. El presente trabajo analizó la respuesta de cultivos de células de Fouquieria splendens ssp. breviflora, expuestos a ácido abscísico (ABA), mediante la caracterización electroforética en cantidad y calidad de las proteínas inducibles de estrés. Se registraron polipéptidos de bajo peso molecular ( 35KDa), comunes bajo la exposición a 10 mM, seguida la asociación con 20 y 30 mM de ABA, quedando aislada la respuesta de la condición de células en cultivo sin la presencia de éste. Plant cell cultures are homogenous experimental systems, highly controllable that allow the study of short and large water stress adaptations without the interference of the different tissues and development of plants. An approach to understand these adaptations is through the presence of induced proteins; as a result of changes in genetic expression. This work analyze the response of Fouquieria splendens ssp. breviflora cell cultures exposed to abscisic acid (ABA), through the electrophoretic characterization of quantity and quality of stress induced proteins. There were recorded low molecular weight polypeptides ( 35kDa), common in experiments under ABA 10mM, followed by the association with 20 and 30mM ABA conditions, with a particularly response of cell cultures without the stress agent.

La trichinellosis es una enfermedad parasitaria zoonótica y cosmopolita, se debe al consumo de carne deficientemente cocida, principalmente proveniente del cerdo, diversos estudios avalan la eficacia de la administración de inmunoterapia. Se ha caracterizado un antígeno inmunodominante de 45 kDa y se plantea como objetivo evaluar la presencia de anticuerpos IgA, IgM e IgG anti-Trichinella spiralis a lo largo de la infección, así como el comportamiento en la administración de la inmunización de 45 kDa de Trichinella spiralis (T. spiralis) administrado por vía sublingual y vía parenteral. Se utilizaron 36 murinos (Long Evans), seis para la infección y purificación del antígeno de 45 kDa, 30 para formar los grupos de trabajo, control sano (cinco murinos), control infectado (cinco murinos), y 20 para los grupos experimentales, se inmunizaron dos grupos con cuatro dosis (0, 7, 14 y 21 días) del inmunógeno de 45 KDa de T. spiralis, uno por vía sublingual y otro por vía parenteral y se retaron con 500 larvas infectantes (LI) de T. spiralis siete días después de la ultima inmunización y dos grupos más se infectaron con 500 LI y se inmunizaron a las cuatro semanas postinfección por ambas vías. La respuesta se evaluó por inmunofluorescencia indirecta (IFI) por microscopia confocal para determinar la respuesta humoral con anticuerpos de clase IgG, IgM e IgA. Trichinellosis is a cosmopolitan zoonotic disease produced mainly by the consumption of poorly cooked swine meat. Several studies have probed the efficiency of immunotherapy as a method for the treatment of trichinellosis. In this work, a 45 kDa immunodominant antigen was characterized, and the presence of IgA, IgM and IgG anti-Trichinella spiralis antibodies was evaluated during the course of the infection. In addition, the differences between sublingual and parenteral administration of the 45 kDa T. spiralis antigen were determined. Long Evans rats were used both to purify the 45 kDa antigen and to evaluate the immune response produced in six different groups: healthy and infected controls; two groups of immunized murines (sublingually and parenterally) with 4 doses of the 45 kDa T. spiralis immunogen administered at days 0, 7, 14 and 21 and challenged with 500 T. spiralis infective larvae (IL) 7 days after the last immunization; and finally, two groups of murines infected with 500 IL of T. spiralis, immunized at week 4 post infection by the same two routes. The humoral response was evaluated by indirect immunofluorescence by confocal microscopyin order to determine the presence of IgA, IgM and IgG antibodies.

The minimum length of stem required for production of flowers in the C3 desert shrub ocotillo (Fouquieria splendens) has been widely accepted as 1 m since 1943. Long-term studies in the Chihuahuan Desert indicate that this threshold is no longer acceptable. During 2003–2006, 15 ocotillo stems shorter than 1 m produced 1–32 flowers each. The shortest stem on which flowers were produced was 62 cm long. Although fully capable of producing flowers, the contribution of stems

Molecular sequence data from the 18S‐26S rDNA internal transcribed spacer (ITS) region support the monophyly of Fouquieria sensu lato (Fouquieriaceae) and the three subgenera (subg. Fouquieria, subg. Bronnia, subg. Idria) previously recognized within it. Resolution within subg. Fouquieria differs somewhat between parsimony and maximum likelihood (ML) trees. Section Fouquieria and sect. Ocotilla within subg. Fouquieria are not well supported as monophyletic groups. Uncertainty regarding placement of the root within Fouquieriaceae makes discussion of character evolution within the family difficult. Three root positions are consistent with rate-constant evolution of ITS sequences: (1) along the branch to subg. Idria, (2) along the branch to subg. Bronnia, and (3) along the branch to subg. Fouquieria. The first root position listed is equivalent to an outgroup rooting. The third root position listed is equivalent to a midpoint rooting. Of the three root positions above, only the third is along a branch that may be sufficiently long to act as a long-branch attractor. The first two root positions would result in character reconstruction suggesting that succulent growth forms and white floral pigmentation are ancestral within the family, with shifts to woody growth forms and to red floral pigmentation. The third root position results in equivocal reconstruction of the ancestral growth form, equivocal reconstruction of ancestral floral pigmentation in parsimony trees, and a suggestion of white floral pigmentation as ancestral in ML trees. Two previous hypotheses of polyploid origins are compatible with the molecular data presented here: (1) origin of the tetraploid F. diguetii from F. macdougalii, and (2) allopolyploid origin of the hexaploid F. burragei from the tetraploid F. diguetii and a diploid species similar to F. splendens. Direct descent of the hexaploid F. columnaris from the subg. Bronnia lineage is not supported by our data. An amphiploid origin of F. columnaris involving a member of the subg. Bronnia lineage and an extinct taxon outside subg. Bronnia, however, cannot be ruled out.

Litterfall and phenological patterns for six structurally important perennial species of a desert scrub community in Mexico ( Jatropha cinerea, J. cuneata, Fouquieria diguetti, Bursera microphylla, Cyrtocarpa edulis and Prosopis articulata ) are described for a 34-month period. The total litter obtained for the community in an experimental plot was 1·2 t ha −1 year −1 . Results showed that species could be grouped according to their production of vegetative structures in relation to water availability; this production of vegetative structures was related to species-specific leaf morphology. Conversely, the production of sexual structures depended on temperature and humidity.

Seedling emergence of psammophiles (plants restricted to active dunes) was examined with germination experiments and with field observations at the Algodones Dunes, California, U.S.A., and the Sierra del Rosario Dunes, Sonora, Mexico. In the field, perennial psammophiles germinated in response to smaller rainfall triggers (≥ 10 mm) than other woody desert plants (≥ 16 mm). In germination experiments, seedlings of three perennial psammophiles, Astragalus magdalenae var. peirsonii, Helianthus niveus subsp. tephrodes , and Palafoxia arida var. gigantea , emerged in larger numbers from greater soil depths than those of three nonpsammophiles, Cercidium microphyllum, Fouquieria splendens , and Palafoxia arida var. arida . Seed size for these six species did not correlate in any consistent fashion with emergence depth, suggesting that food reserves are not the only variable that ensures emergence of deeply buried psammophile seeds.

The demography of woody desert plants along the Colorado River in Grand Canyon, Arizona, USA, was analyzed using 355 pairs of replicated photographs taken as long ago as 1872. Longevity, recruitment, and mortality were determined for 38 species characteristic of ungrazed desert scrub. Indi- vidual plants that survived 100 yr or more included Acacia greggii, Ambrosia dumosa, Atriplex canescens, A. confertifolia, Echinocactus polycephalus, Ephedra spp., Fouquieria splendens, Larrea tridentata, Lycium andersonii, Opuntia acanthocarpa, 0. basilaris, 0. erinacea, Pleuraphis rigida, and Yucca angustissima. This is the first evidence of long lifespan for most of these species, particularly the succulents. Most of the long-lived species registered overall increases in population during the past century. Only four species with lifespans > 100 yr had a net loss of individuals between 1889 and the present, and only two decreased between 1923 and the present. It seems likely that climatic fluctuations over the past century are largely responsible for these recruitment and mor- tality patterns; however, nurse plants, predation refuges and other biotic factors may also play a role.

Fossil pollen from packrat (Neotoma sp.) middens indicate that elements of the modern Sonoran Desert, such as Bursera microphylla (elephant tree), have been established within the Sierra Bacha of Sonora, Mexico, for the last 10,000 years. However, Fouquieria columnaris (boojum tree) grew on xeric east-facing slopes prior to c. 9000 years ago, indicating locally stronger upwelling or greater effective precipitation over modern conditions. Nearmodern environments were established sometime prior to c. 5400 years ago. The lack of correspondence between pollen-based vegetation reconstructions from middens and nearby marine sediment cores probably reflects different source areas for the pollen.

Arborescent stem succulents in tropical and subtropical deserts depend on scarce and uncertain rainfall. Gas exchange and the diurnal acidity fluctuation of bark and ephemeral leaves were measured under both dry and moist soil conditions in Fouquieria columnaris (cirio or boojum tree) and Pachycormus discolor (torote blanco or elephant tree) and in stems of the columnar cactus Pachycereus pringlei (cardon) in the Central Desert of Baja California, Mexico. Results demonstrated that ephemeral leaves were the only site of exogenous CO2 assimilation in F. columnaris and P. discolor; there was no measurable gas exchange across the green photosynthetic bark. The pattern of gas exchange in F. columnaris and P. discolor was consistent with that of C3 plants. P. pringlei was shown to be a typical Crassulacean acid metabolism plant on the basis of acid fluctuations and gas exchange. Chlorophyll fluorescence studies of the green bark of F. columnaris and P. discolor indicated that this tissue is photosynthetically functional, and that CO2 assimilation can rise above the compensation point under high CO2 concentrations, such as may occur within the plant. The green photosynthetic bark of these species may be an adaptation for surviving prolonged drought and may function to recycle endogenous respiratory C02, thus maintaining the plant's energy reserves and permitting rapid production of leaves in response to infrequent rains.

El estrés es considerado una desviación significativa de las condiciones óptimas de vida, que induce cambios que en primera instancia son reversibles, pero también pueden ser permanentes. El estrés hídrico desencadena una serie de respuestas tales como la biosíntesis de metabolitos secundarios y la activación simultánea de la síntesis de proteínas específicas denominadas de estrés, hasta cambios en el desarrollo y/o reproducción de las plantas. En el presente trabajo se evaluó la respuesta al estrés hídrico de Fouquieria splendens ssp. breviflora, mediante el análisis bioquímico y fisiológico de los brotes foliares producidos bajo condiciones de estrés hídrico con la adición de polietilenglicol y ácido abscísico. Se evidenció la presencia de elementos traqueales almacenadores de agua en los brotes foliares además de que su contenido de proteína total y prolina libre se incrementó bajo la presencia de estos agentes, lo que mostró una respuesta fisiológica de Fouquieria splendens ssp. breviflora que bien pudiera evidenciar los primeros mecanismos que le permiten responder a las condiciones de estrés hídrico generadas por el ambiente árido en el que se desarrolla.

Short-shoot leaves on the terminal stem segments of the drought-deciduous desert shrub ocotillo (Fouquieria splendens) are retained long after long-shoot leaves are lost through senescence and abscission. This formerly unreported observation has relevance for determining whether a terminal stem segment is new or old, because newly produced segments are routinely associated with the presence of long-shoot leaves. It is now clear that the absence of long-shoot leaves on a terminal stem segment cannot be used as unequivocal evidence that the segment is old. The relatively rapid loss of long-shoot leaves from new terminal stem segments may be an adaptation to reduce herbivory by accelerating maturation of the spine that develops from tissues left by each senescing long-shoot petiole.

Leaves and stems of Fouquieria splendens were found to accumulate flavonoid aglycones on their surfaces. Three flavones and five flavonols have been identified.

BowERs, JAIcE E. (U.S. Geological Survey, 1675 W. Anklam Road, Tucson, AZ 85745) AND MARK A. DIMMITr (Arizona-Sonora Desert Museum, 2021 N. Kinney Road, Tucson, AZ 85743). Flowering phenology of six woody plants in the northern Sonoran Desert. Bull. Torrey Bot. Club 121: 215-229. 1994.-Climatic and flowering data from a site in the northern Sonoran Desert of southern Arizona were used to define flowering triggers and developmental requirements for 6 woody plants. These formulations were then used to predict flowering dates at a second northern Sonoran Desert site. It was determined that flowering is triggered by rain in Larrea tridentata (DC.) Cov., Fouquieria splendens Engelm., Encelia farinosa A. Gray, Ambrosia deltoidea (A. Gray) Payne and Acacia constricta Benth., and that flowering is triggered by photoperiod in Cercidium microphyllum (Torr.) Rose & Johnst. The base temperature for floral development in L. tridentata, F. splendens, E. farinosa, A. deltoidea and C. microphyllum is about 10?C. Their mean degree-day requirements range from 414 to 719. Acacia constricta requires 522 degree-days above 15?C. Minimum rainfall triggers varied from 9 mm forAmbrosia to 20 mm for Encelia. Flowering time in C. microphyllum may reflect phylogenetic constraints, while flowering time in F. splendens may be strongly influenced by pollinator availability. Flowering times of the remaining species seem constrained more by climate than by biotic considerations such as phylogeny, seed germination and competition for pollinators.