2020
de la Barrera, E.; Aguirre-Pérez, I. A.; Ibarra-Otero, B. A.; Villalvazo-Figueroa, E. A.; Díaz-Álvarez, E. A.
No country for new seeds: Food and environmental security implications of Mexico's intended ban on GM crops Journal Article
In: Transgenic Research, vol. 29, no. 1, pp. 156-170, 2020.
Abstract | Links | BibTeX | Tags: agroecology, biodiversity, biosafety, climate change, public policy, science policy
@article{delaBarrera2020b,
title = {No country for new seeds: Food and environmental security implications of Mexico's intended ban on GM crops},
author = {E. de la Barrera and I. A. Aguirre-Pérez and B. A. Ibarra-Otero and E. A. Villalvazo-Figueroa and E. A. Díaz-Álvarez},
url = {https://link.springer.com/article/10.1007/s11248-019-00186-7},
doi = {10.1007/s11248-019-00186-7},
year = {2020},
date = {2020-02-03},
journal = {Transgenic Research},
volume = {29},
number = {1},
pages = {156-170},
abstract = {An intended generalized ban on the "introduction and use of transgenic seeds" has been announced by the Mexican government, which, unlike the other agricultural programs under this administration, lacks a budget and rules of operation. In this policy brief we consider scenarios of implementing such an intended ban, de-regulating the use of genetically modified crops, or an intermediate scenario under the existing biosafety regulations. We recommend maintaining the status quo given its potential contributions to food and environmental security, in addition to a better economic outlook. However, a greater impulse needs to be given by the federal government to foment the domestic development of GM crops that are pertinent for Mexican agri-food needs, in addition to funding the development and implementation of various agro-ecological practices that increase biodiversity in food production units.},
keywords = {agroecology, biodiversity, biosafety, climate change, public policy, science policy},
pubstate = {published},
tppubtype = {article}
}
An intended generalized ban on the "introduction and use of transgenic seeds" has been announced by the Mexican government, which, unlike the other agricultural programs under this administration, lacks a budget and rules of operation. In this policy brief we consider scenarios of implementing such an intended ban, de-regulating the use of genetically modified crops, or an intermediate scenario under the existing biosafety regulations. We recommend maintaining the status quo given its potential contributions to food and environmental security, in addition to a better economic outlook. However, a greater impulse needs to be given by the federal government to foment the domestic development of GM crops that are pertinent for Mexican agri-food needs, in addition to funding the development and implementation of various agro-ecological practices that increase biodiversity in food production units.
2019
Díaz-Álvarez, E. A.; Felix, J. D.; de la Barrera, E.
Elemental and isotopic assessment for Colombian orchids from a montane cloud forest: a baseline for global environmental change Journal Article
In: Acta Physiologiae Plantarum, vol. 41, no. 6, pp. 99, 2019.
Abstract | Links | BibTeX | Tags: biodiversity, CAM, ecophysiology, epiphytes, global change, nitrogen, orchid, photosynthesis, stable isotopes
@article{Díaz-Álvarez2019,
title = {Elemental and isotopic assessment for Colombian orchids from a montane cloud forest: a baseline for global environmental change},
author = {E. A. Díaz-Álvarez and J. D. Felix and E. de la Barrera},
url = {https://rdcu.be/bCRG6},
doi = {10.1007/s11738-019-2893-y},
year = {2019},
date = {2019-05-16},
journal = {Acta Physiologiae Plantarum},
volume = {41},
number = {6},
pages = {99},
abstract = {Orchidaceae is the largest family of plants, reaching its maximum diversity in Colombia where 4000 species have been registered. One particular ecosystem with high diversity of orchids is the tropical montane cloud forest characterized by high humidity and low air temperatures. However, due to anthropic pressure such as land use change its area has been reduced. This is not the only anthropic disturbance that can affect the continuity of this forest and orchids, climate change and nitrogen deposition also become threats. By means of elemental composition and isotopic measurements of carbon and nitrogen, we determined the photosynthetic pathway for orchids from a tropical cloud forest in Colombia, for which, we also evaluated the nutritional status of nitrogen and its relationship with atmospheric deposition. We found 46 species from 18 genera; of these, 19 species were epiphytic, 9 lithophytic and 18 terrestrials. The carbon content was not significantly different among the species evaluated, averaging 46.4 ± 0.41% (dry weight). In turn, only one terrestrial orchid had a nitrogen content above 2.2%, averaged 1.4 ± 0.07% for the remaining 45 species. The δ13C that averaged − 28.1 ± 0.4‰ for 45 species was typical of C3 plants, while only one species, whose δ13C of 18.8‰ can be considered CAM. The δ15N values for 44 orchids were negative, in total they ranged from − 8.1 to 4.5‰. It can be concluded that the temperatures in this area are not yet high enough to produce a noticeable change in photosynthesis as evidenced by the carbon content of orchids, however, the expected rise would bring harmful consequences for these populations of orchids, especially when considering that these orchids were collected at the highest altitudinal range of the region. Moreover, the rates of nitrogen deposition are not high enough yet to leave a significant signal in the vegetation.},
keywords = {biodiversity, CAM, ecophysiology, epiphytes, global change, nitrogen, orchid, photosynthesis, stable isotopes},
pubstate = {published},
tppubtype = {article}
}
Orchidaceae is the largest family of plants, reaching its maximum diversity in Colombia where 4000 species have been registered. One particular ecosystem with high diversity of orchids is the tropical montane cloud forest characterized by high humidity and low air temperatures. However, due to anthropic pressure such as land use change its area has been reduced. This is not the only anthropic disturbance that can affect the continuity of this forest and orchids, climate change and nitrogen deposition also become threats. By means of elemental composition and isotopic measurements of carbon and nitrogen, we determined the photosynthetic pathway for orchids from a tropical cloud forest in Colombia, for which, we also evaluated the nutritional status of nitrogen and its relationship with atmospheric deposition. We found 46 species from 18 genera; of these, 19 species were epiphytic, 9 lithophytic and 18 terrestrials. The carbon content was not significantly different among the species evaluated, averaging 46.4 ± 0.41% (dry weight). In turn, only one terrestrial orchid had a nitrogen content above 2.2%, averaged 1.4 ± 0.07% for the remaining 45 species. The δ13C that averaged − 28.1 ± 0.4‰ for 45 species was typical of C3 plants, while only one species, whose δ13C of 18.8‰ can be considered CAM. The δ15N values for 44 orchids were negative, in total they ranged from − 8.1 to 4.5‰. It can be concluded that the temperatures in this area are not yet high enough to produce a noticeable change in photosynthesis as evidenced by the carbon content of orchids, however, the expected rise would bring harmful consequences for these populations of orchids, especially when considering that these orchids were collected at the highest altitudinal range of the region. Moreover, the rates of nitrogen deposition are not high enough yet to leave a significant signal in the vegetation.
2015
Díaz-Álvarez, E. A.; Lindig-Cisneros, R.; de la Barrera, E.
Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa Journal Article
In: PeerJ, vol. 3, pp. e1021, 2015.
Abstract | Links | BibTeX | Tags: acid rain, biodiversity, CAM, conservation physiology, d15N, global change, Laelia, neotropical, nitrogen, orchid, plant nutrition, pollution, stable isotopes
@article{Díaz-Álvarez2015,
title = {Responses to simulated nitrogen deposition by the neotropical epiphytic orchid Laelia speciosa},
author = {E. A. Díaz-Álvarez and R. Lindig-Cisneros and E. de la Barrera},
url = {https://peerj.com/articles/1021/
https://agro.mx/wp-content/uploads/2015/06/031-Díaz-Alvarez-et-al-2015-PeerJ-Laelia.pdf},
doi = {10.7717/peerj.1021},
year = {2015},
date = {2015-06-18},
journal = {PeerJ},
volume = {3},
pages = {e1021},
abstract = {Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha-1 yr-1) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr–1, the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr–1 than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m-2 and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr–1. The δ13C for leaves averaged –14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ15N decreased as the nitrogen dose increased from 0.9 ±0.1‰ under 2.5 kg N ha-1 yr-1 to – 3.1 ± 0.2 ‰ under 80 kg N ha-1 yr-1, indicating that orchids preferentially assimilate NH4+ rather than NO3– of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species.},
keywords = {acid rain, biodiversity, CAM, conservation physiology, d15N, global change, Laelia, neotropical, nitrogen, orchid, plant nutrition, pollution, stable isotopes},
pubstate = {published},
tppubtype = {article}
}
Potential ecophysiological responses to nitrogen deposition, which is considered to be one of the leading causes for global biodiversity loss, were studied for the endangered endemic Mexican epiphytic orchid, Laelia speciosa, via a shadehouse dose-response experiment (doses were 2.5, 5, 10, 20, 40, and 80 kg N ha-1 yr-1) in order to assess the potential risk facing this orchid given impending scenarios of nitrogen deposition. Lower doses of nitrogen of up to 20 kg N ha yr–1, the dose that led to optimal plant performance, acted as fertilizer. For instance, the production of leaves and pseudobulbs were respectively 35% and 36% greater for plants receiving 20 kg N ha yr–1 than under any other dose. Also, the chlorophyll content and quantum yield peaked at 0.66 ± 0.03 g m-2 and 0.85 ± 0.01, respectively, for plants growing under the optimum dose. In contrast, toxic effects were observed at the higher doses of 40 and 80 kg N ha yr–1. The δ13C for leaves averaged –14.7 ± 0.2‰ regardless of the nitrogen dose. In turn, δ15N decreased as the nitrogen dose increased from 0.9 ±0.1‰ under 2.5 kg N ha-1 yr-1 to – 3.1 ± 0.2 ‰ under 80 kg N ha-1 yr-1, indicating that orchids preferentially assimilate NH4+ rather than NO3– of the solution under higher doses of nitrogen. Laelia speciosa showed a clear response to inputs of nitrogen, thus, increasing rates of atmospheric nitrogen deposition can pose an important threat for this species.