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1.
ACS Omega ; 9(18): 19786-19795, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38737020

RESUMO

This study looked at using modified camelina oil to develop sustainable coatings that could replace those derived from petroleum-based materials for use in packaging and other industrial sectors. Solvent-free synthesis of maleic anhydride grafted camelina oil (MCO) was carried out at two different temperatures (200 and 230 °C) to obtain sustainable hydrophobic coating materials for paper substrates. Maleic anhydride grafting of camelina oil was confirmed with attenuated total reflectance-Fourier transform infrared and NMR spectroscopic techniques, and up to 16% grafting of maleic anhydride was achieved, as determined by the titration method. MCO, obtained at different reaction temperatures, was coated onto cellulosic paper and evaluated for its hydrophobicity, mechanical, oxygen, and water vapor barrier properties. Scanning electron microscopy indicated the homogeneous dispersion of coating material onto the paper substrate. MCO-coated papers (MCO-200C paper and MCO-230C paper) provided a water contact angle of above 90° which indicates that the modified oil was working as a hydrophobic coating. Water vapor permeability (WVP) testing of coated papers revealed a reduction in WVP of up to 94% in comparison to the uncoated paper. Moreover, an improved oxygen barrier property was also observed for paper coated with both types of MCO. Analysis of the mechanical properties showed a greater than 70% retention of tensile strength and up to a five-fold increase in elongation at break of coated versus uncoated papers. Overall, the results show that camelina oil, a renewable resource, can be modified to produce environmentally friendly hydrophobic coating materials with improved mechanical and water vapor barrier properties that can serve as a potential coating material in the packaging industry. The results of this research could find applications in the huge paper packaging industries, specially in food packaging.

2.
Heliyon ; 10(7): e27975, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560240

RESUMO

Euphorbia lagascae Spreng is a promising emerging oilseed crop, with its seed oil accounting for approximately 50% of the seed weight. Euphorbia oil contains a significant amount of vernolic acid, comprising two-thirds of its composition, which boasts various industrial applications, including acting as a stabilizer-plasticizer and natural dye. However, this species was known to have a high degree of seed-shattering and a low germination rate, which act as two important barriers to large-scale production and exploitation. Therefore, the objective of this study is to determine the genetic control of seed germination and seed-shattering traits in order to develop a reliable pipeline that would be applicable for industries and breeders to select superior E. lagascae lines and design a robust breeding scheme in a short time at reduced labor costs. For this objective, five different wild-type genotypes of E. lagascae that demonstrated high germination potential were crossed with an ethyl methanesulfonate (EMS) mutant genotype that produces non-shattering capsules. The F2 populations from two successful crosses (A and B) were separated into three different treated groups for seed germination evaluation and to study the segregation of 200 individuals per F2 population. The three treatments were: light, gibberellic acid (GA3), and control treatment. Consequently, plants treated with approximately 250 µmol/m2/s of light showed significant improvement in germination up to 75% in cross A and 82.4 % in cross B compared with the control plants and the group treated with 0.05% GA3. According to the chi-square test results, the inheritance pattern of seed germination in response to light treatment follows a 3:1 segregation ratio between germinated and non-germinated seeds, indicating a dominant gene action in the F2 generation. The same conclusion was followed for the shattering trait in the group treated with light, which was also simply inherited as a 3:1 ratio for shattering vs. non-shattering capsules. Our results emphasize the importance and significance of light treatment in producing uniform populations through acceptable germination and shattering resistance of the mutant genotypes of E. lagascae. This is the first report of light treatment that significantly improved seed germination of E. lagascae, which may enhance efforts in the development of this new industrial crop as a feedstock for vernolic acid production.

3.
Plant Methods ; 20(1): 14, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267941

RESUMO

BACKGROUND: The potential of plant-based sources of vernolic acid to provide agricultural producers with a market diversification opportunity and industrial manufacturers with a renewable, environmentally friendly chemical feedstock is immense. The herbaceous wild spurge or caper spurge (Euphorbia lagascae Spreng) is the most promising source of vernolic acid, containing an average oil content of 50%, of which around 60% is vernolic acid. Its seed yield ranges between 500 and 2000 kg ha-1, and a theoretical yield of 180 kg ha-1 of pure vernolic acid is possible. The objective of this research was to characterize the flower and whole plant morphology so to allow for the development of a method to efficiently hybridize E. lagasce plants for breeding purposes. RESULTS: In this study, we have characterized the flower and whole plant morphology in detail, thereby, developing an efficient method for hybridization of E. lagasce to allow for its breeding and improvement as a novel oil crop. Such method was not described previously in the literature making it difficult to breed this crop. We believe that the method will be of great value to plant breeders working on optimizing the crop, particularly in terms of the development of non-shattering cultivars with enhanced germination potential. CONCLUSIONS: The successful development of this crop through plant breeding could provide substantial economic benefits to farmers by offering them a new industrial oilseed crop. This research could prove invaluable in unlocking the potential of E. lagasce, and in turn, the potential of vernolic acid as a renewable, environmentally friendly source of chemical feedstock.

4.
RSC Adv ; 12(42): 27230-27245, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36321163

RESUMO

Global environmental pollution is a growing concern, especially the release of carbon dioxide from the use of petroleum derived materials which negatively impacts our environment's natural greenhouse gas level. Extensive efforts have been made to explore the conversion of renewable raw materials (vegetable oils) into bio-based products with similar or enhanced properties to those derived from petroleum. However, these edible plant oils, commonly used for human food consumption, are often not suitable raw materials for industrial applications. Hence, there is an increasing interest in exploring the use of non-edible plant oils for industrial applications. One such emerging oil seed crop is Camelina sativa, generally known as camelina, which has limited use as a food oil and so is currently being explored as a feedstock for various industrial applications in both Europe and North America. Camelina oil is highly unsaturated, making it an ideal potential AGH feedstock for the manufacture of lower carbon footprint, biobased products that reduce our dependency on petroleum resources and thus help to combat climate change. This review presents a brief description of camelina highlighting its composition and its production in comparison with traditional plant oils. The main focus is to summarize recent data on valorization of camelina oil by various chemical means, with specific emphasis on their industrial applications in biofuels, adhesives and coatings, biopolymers and bio-composites, alkyd resins, cosmetics, and agriculture. The review concludes with a discussion on current challenges and future opportunities of camelina oil valorization into various industrial products.

5.
R Soc Open Sci ; 4(1): 160879, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28280587

RESUMO

Identity recognition systems allow plants to tailor competitive phenotypes in response to the genetic relatedness of neighbours. There is limited evidence for the existence of recognition systems in crop species and whether they operate at a level that would allow for identification of different degrees of relatedness. Here, we test the responses of commercial soya bean cultivars to neighbours of varying genetic relatedness consisting of other commercial cultivars (intraspecific), its wild progenitor Glycine soja, and another leguminous species Phaseolus vulgaris (interspecific). We found, for the first time to our knowledge, that a commercial soya bean cultivar, OAC Wallace, showed identity recognition responses to neighbours at different levels of genetic relatedness. OAC Wallace showed no response when grown with other commercial soya bean cultivars (intra-specific neighbours), showed increased allocation to leaves compared with stems with wild soya beans (highly related wild progenitor species), and increased allocation to leaves compared with stems and roots with white beans (interspecific neighbours). Wild soya bean also responded to identity recognition but these responses involved changes in biomass allocation towards stems instead of leaves suggesting that identity recognition responses are species-specific and consistent with the ecology of the species. In conclusion, elucidating identity recognition in crops may provide further knowledge into mechanisms of crop competition and the relationship between crop density and yield.

6.
PLoS One ; 7(6): e39440, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22768079

RESUMO

BACKGROUND: Feral populations of cultivated crops can pose challenges to novel trait confinement within agricultural landscapes. Simulation models can be helpful in investigating the underlying dynamics of feral populations and determining suitable management options. METHODOLOGY/PRINCIPAL FINDINGS: We developed a stage-structured matrix population model for roadside feral alfalfa populations occurring in southern Manitoba, Canada. The model accounted for the existence of density-dependence and recruitment subsidy in feral populations. We used the model to investigate the long-term dynamics of feral alfalfa populations, and to evaluate the effectiveness of simulated management strategies such as herbicide application and mowing in controlling feral alfalfa. Results suggest that alfalfa populations occurring in roadside habitats can be persistent and less likely to go extinct under current roadverge management scenarios. Management attempts focused on controlling adult plants alone can be counterproductive due to the presence of density-dependent effects. Targeted herbicide application, which can achieve complete control of seedlings, rosettes and established plants, will be an effective strategy, but the seedbank population may contribute to new recruits. In regions where roadside mowing is regularly practiced, devising a timely mowing strategy (early- to mid-August for southern Manitoba), one that can totally prevent seed production, will be a feasible option for managing feral alfalfa populations. CONCLUSIONS/SIGNIFICANCE: Feral alfalfa populations can be persistent in roadside habitats. Timely mowing or regular targeted herbicide application will be effective in managing feral alfalfa populations and limit feral-population-mediated gene flow in alfalfa. However, in the context of novel trait confinement, the extent to which feral alfalfa populations need to be managed will be dictated by the tolerance levels established by specific production systems for specific traits. The modelling framework outlined in this paper could be applied to other perennial herbaceous plants with similar life-history characteristics.


Assuntos
Agricultura , Medicago sativa/crescimento & desenvolvimento , Modelos Biológicos , Manitoba , Dinâmica Populacional , Fatores de Tempo
7.
Transgenic Res ; 20(2): 397-407, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20635142

RESUMO

Alfalfa is a highly outcrossing perennial species that can be noticed in roadsides as feral populations. There remains little information available on the extent of feral alfalfa populations in western Canadian prairies and their role in gene flow. The main objectives of this study were (a) to document the occurrence of feral alfalfa populations, and (b) to estimate the levels of outcrossing facilitated by feral populations. A roadside survey confirmed widespread occurrence of feral alfalfa populations, particularly in alfalfa growing regions. The feral populations were dynamic and their frequency ranged from 0.2 to 1.7 populations km(-1). In many cases, the nearest feral alfalfa population from alfalfa production field was located within a distance sufficient for outcrossing in alfalfa. The gene flow study confirmed that genes can move back and forth between feral and cultivated alfalfa populations. In this study, the estimated outcrossing levels were 62% (seed fields to feral), 78% (feral to seed fields), 82% (hay fields to feral) and 85% (feral to feral). Overall, the results show that feral alfalfa plants are prevalent in alfalfa producing regions in western Canada and they can serve as bridges for gene flow at landscape level. Management of feral populations should be considered, if gene flow is a concern. Emphasis on preventing seed spill/escapes and intentional roadside planting of alfalfa cultivars will be particularly helpful. Further, realistic and pragmatic threshold levels should be established for markets sensitive to the presence of GE traits.


Assuntos
Produtos Agrícolas/genética , Fluxo Gênico , Medicago sativa/genética , Cruzamentos Genéticos , Engenharia Genética , Genótipo , Manitoba , Medicago sativa/classificação , Medicago sativa/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética
8.
Environ Sci Pollut Res Int ; 17(8): 1448-59, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20393805

RESUMO

PURPOSE: Feral populations of cultivated crops can act as reservoirs for novel genetically engineered (GE) traits and aid in trait movement at the landscape level. However, little information is available on the potential of cultivated crops to become feral. In this study, we investigated the ferality of alfalfa populations (non-GE version) occurring in roadside habitats. Knowledge on the nature of roadside alfalfa populations would be useful for designing efficient trait confinement protocols and coexistence strategies in alfalfa. METHODS: We investigated roadside alfalfa populations from 2006 to 2009 in three rural municipalities (Hanover, MacDonald, and Springfield) in Southern Manitoba, Canada. We studied the demography of these populations including seedbank, seedling recruitment, and fecundity and examined the impact of road verge mowing on key life stages of these populations. We also compared the growth and reproductive attributes of roadside and cultivated alfalfa populations. RESULTS: Alfalfa is reproductively successful in roadside habitats and capable of establishing self-perpetuating populations. A substantial portion of the alfalfa seeds we extracted from seedbank samples were viable but not germinable, suggesting some degree of seedbank persistence in roadside habitats. In the roadside habitat, alfalfa seedlings recruited successfully, however, seedling mortality was high when seedlings were in close proximity to well-established alfalfa plants. Mowing dramatically reduced the reproductive success of roadside alfalfa. Generally, the growth and reproduction of roadside alfalfa was comparable to cultivated alfalfa except for total fecundity. CONCLUSIONS: Considering the long lifespan (>10 years) of alfalfa and the levels of fecundity, seedbank, and seedling survival we observed, long-term persistence of roadside alfalfa populations seems reasonable. In the context of novel trait confinement, our results suggest that feral alfalfa populations required to be managed if there is a desire/need to confine novel traits in alfalfa.


Assuntos
Medicago sativa/crescimento & desenvolvimento , Biodiversidade , Ecossistema , Padrões de Herança , Manitoba , Medicago sativa/classificação , Medicago sativa/genética
9.
Transgenic Res ; 19(3): 449-60, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19763864

RESUMO

Transgenic wheat (Triticum aestivum L.) with improved agronomic traits is currently being field-tested. Gene flow in space is well-documented, but isolation in time has not received comparable attention. Here, we report the results of a field experiment that investigated reductions in intraspecific gene flow associated with temporal isolation of flowering between T. aestivum conspecifics. Pollen-mediated gene flow (PMGF) between an imazamox-resistant (IR) volunteer wheat population and a non-IR spring wheat crop was assessed over a range of volunteer emergence timings and plant population densities that collectively promoted flowering asynchrony. Natural hybridization events between the two populations were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) lines. Based on the examination of >545,000 seedlings, we identified a hybridization window in spring wheat approximately 125 growing degree-days (GDD) in length. We found a sizeable reduction (two- to four-fold) in gene flow frequencies when flowering occurred outside of this window. The hybridization window identified in this research also will serve to temporally isolate neighboring wheat crops. However, strict control of volunteer populations or spatial isolation of neighbouring crops emerging within a 125 GDD hybridization window will be necessary to maintain low frequencies of PMGF in spring wheat fields. The model developed herein also is likely to be applicable to other wind-pollinated species.


Assuntos
Agricultura/métodos , Fluxo Gênico/genética , Hibridização Genética , Plantas Geneticamente Modificadas/genética , Pólen/genética , Triticum/genética , Genética Populacional , Resistência a Herbicidas/genética , Imidazóis , Modelos Biológicos , Dinâmica Populacional , Fatores de Tempo
10.
Environ Biosafety Res ; 9(2): 75-85, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21288463

RESUMO

Prunus species are important commercial fruit (plums, apricot, peach and cherries), nut (almond) and ornamental trees cultivated broadly worldwide. This review compiles information from available literature on Prunus species in regard to gene flow and hybridization within this complex of species. The review serves as a resource for environmental risk assessment related to pollen mediated gene flow and the release of transgenic Prunus. It reveals that Prunus species, especially plums and cherries show high potential for transgene flow. A range of characteristics including; genetic diversity, genetic bridging capacity, inter- and intra-specific genetic compatibility, self sterility (in most species), high frequency of open pollination, insect assisted pollination, perennial nature, complex phenotypic architecture (canopy height, heterogeneous crown, number of flowers produced in an individual plant), tendency to escape from cultivation, and the existence of ornamental and road side Prunus species suggest that there is a tremendous and complicated ability for pollen mediated gene movement among Prunus species. Ploidy differences among Prunus species do not necessarily provide genetic segregation. The characteristics of Prunu s species highlight the complexity of maintaining coexistence between GM and non-GM Prunus if there were commercial production of GM Prunus species. The results of this review suggest that the commercialization of one GM Prunus species can create coexistence issues for commercial non-GM Prunus production. Despite advances in molecular markers and genetic analysis in agroecology, there remains limited information on the ecological diversity, metapopulation nature, population dynamics, and direct measures of gene flow among different subgenera represented in the Prunus genus. Robust environmental impact, biosafety and coexistence assessments for GM Prunus species will require better understanding of the mechanisms of gene flow and hybridization among species within the Prunus species complex.


Assuntos
Produtos Agrícolas/genética , Fluxo Gênico , Plantas Geneticamente Modificadas/genética , Prunus/genética , Contenção de Riscos Biológicos/métodos , Hibridização Genética , Plantas Geneticamente Modificadas/fisiologia , Dinâmica Populacional , Prunus/fisiologia , Reprodução , Medição de Risco
11.
Environ Biosafety Res ; 8(3): 141-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20028616

RESUMO

What happens when one nation cultivates a transgenic crop variety but neighboring nations do not? Using alfalfa as a case study, we argue that the potential for international transgene flow is substantial, and therefore, the need for international cooperation in regulatory decisions concerning transgenic crops is imperative. Alfalfa (Medicago sativa, L.) is the major forage crop in North America. Recently, genetically modified (GM) alfalfa received a moratorium on further cultivation in the US on the grounds that the approvals were based on inadequate environmental impact assessments. With their deep root system, symbiotic nitrogen fixation, prolific seed production and prolonged dormancy, alfalfa plants are capable of establishing self-perpetuating (feral) populations in unmanaged environments. Given what is known about alfalfa pollen dispersal, such feral populations could facilitate gene flow between GM and non-GM fields. The border between the US and Canada, particularly in farming areas, is very narrow (< 10 m wide). We surveyed along the US-Canada border and found both alfalfa fields and potentially feral alfalfa plants in the ditches along the border. Our survey results provide evidence of the possibility of cross-border transgene flow, suggesting a need for international co-operative risk assessment initiatives between the US and Canada. Such situations could occur for other crops, in other international border regions as well.


Assuntos
Fluxo Gênico , Cooperação Internacional , Medicago sativa/genética , Plantas Geneticamente Modificadas/genética , Transgenes , Agricultura/legislação & jurisprudência , Canadá , Regulamentação Governamental , Medição de Risco , Estados Unidos
12.
Environ Sci Pollut Res Int ; 16(6): 689-701, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19475440

RESUMO

BACKGROUND, AIM, AND SCOPE: The controversy over the world's first genetically modified (GM) wheat, Roundup Ready wheat (RRW), challenged the efficacy of 'science-based' risk assessment, largely because it excluded the public, particularly farmers, from meaningful input. Risk analysis, in contrast, is broader in orientation as it incorporates scientific data as well as socioeconomic, ethical, and legal concerns, and considers expert and lay input in decision-making. Local knowledge (LK) of farmers is experience-based and represents a rich and reliable source of information regarding the impacts associated with agricultural technology, thereby complementing the scientific data normally used in risk assessment. The overall goal of this study was to explore the role of farmer LK in the a priori risk analysis of RRW. MATERIALS AND METHODS: In 2004, data were collected from farmers using mail surveys sent across the three prairie provinces (i.e., Manitoba, Saskatchewan, and Alberta) in western Canada. A stratified random sampling approach was used whereby four separate sampling districts were identified in regions where wheat was grown for each province. Rural post offices were randomly selected in each sampling district using Canada Post databases such that no one post office exceeded 80 farms and that each sampling district comprised 225-235 test farms (n = 11,040). In total, 1,814 people responded, representing an adjusted response rate for farmers of 33%. A subsequent telephone survey showed there was no non-response bias. RESULTS: The primary benefits associated with RRW were associated with weed control, whereas risks emphasized the importance of market harm, corporate control, agronomic problems, and the likelihood of contamination. Overall, risks were ranked much higher than benefits, and the great majority of farmers were highly critical of RRW commercialization. In total, 83.2% of respondents disagreed that RRW should have unconfined release into the environment. Risk was associated with distrust in government and corporations, previous experience with GM canola, and a strong belief in the importance of community and environment. Farmers were critical of expert-based risk assessment, particularly RRW field trials, and believed that their LK was valuable for assessing agbiotechnology as a whole. DISCUSSION: Over 90% of canola production across the Canadian prairies makes use of herbicide-tolerant (HT) varieties. Yet, respondents were generally uniform in their criticism of RRW, regardless whether they were HT users, non-HT-users, conservation tillage or organic in approach. They had a sophisticated understanding of how GM trait confinement was intrinsically tied to grain system segregation and, ultimately, market accessibility, and were concerned that gene flow in RRW would not be contained. Organic farmers were particularly critical of RRW, in large part because certification standards prohibit the presence of GM traits. Farmers practicing conservation tillage were also at relatively great risk, in part because their dependence on glyphosate to control weeds increases the likelihood that RRW volunteer would become more difficult and costly to control. CONCLUSIONS: This research is the first of its kind to include farmer knowledge in the a priori risk analysis of GM crops and, arguably, given its prairie-wide scope, is the largest scale, independent-farmer-focused study on GM crops ever conducted. The surprising uniformity in attitudes between users and non-users of GM technology and among organic, conventional, conservation tillage and GM using farmers speaks to the ability of farmers to discriminate among HT varieties. Our results clearly show that prairie farmers recognize that the risks associated with RRW commercialization outweigh any benefits. RECOMMENDATIONS AND PERSPECTIVES: Farmer knowledge systems are holistic in nature, incorporating socioeconomic, cultural, political, and agroecological factors that all can contribute meaningfully to the pre-release evaluation of GM crops. The inclusion of farmers and other stakeholders in risk assessment will also help enhance and even restore public confidence in science-focused approaches to risk assessment. Although farmers are highly knowledgeable regarding RRW and arguably any agricultural technology, their expertise continues to be overlooked by decision-makers and regulators across North America.


Assuntos
Resistência a Medicamentos/genética , Glicina/análogos & derivados , Medição de Risco/métodos , Triticum/genética , Agricultura/economia , Agricultura/legislação & jurisprudência , Agricultura/normas , Canadá , Análise Custo-Benefício , Glicina/farmacologia , Conhecimentos, Atitudes e Prática em Saúde , Herbicidas/farmacologia , Plantas Geneticamente Modificadas , Inquéritos e Questionários , Glifosato
13.
Transgenic Res ; 18(6): 841-54, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19387859

RESUMO

Transgenic wheat is currently being field tested with the intent of eventual commercialization. The development of wheat genotypes with novel traits has raised concerns regarding the presence of volunteer wheat populations and the role they may play in facilitating transgene movement. Here, we report the results of a field experiment that investigated the potential of spring wheat plant population density and crop height to minimize gene flow from a herbicide-resistant (HR) volunteer population to a non-HR crop. Pollen-mediated gene flow (PMGF) between the HR volunteer wheat population and four conventional spring wheat genotypes varying in height was assessed over a range of plant population densities. Natural hybridization events between the two cultivars were detected by phenotypically scoring plants in F(1) populations followed by verification with Mendelian segregation ratios in the F(1:2) families. PMGF was strongly associated with crop yield components, but showed no association with flowering synchrony. Maximum observed PMGF was always less than 0.6%, regardless of crop height and density. The frequency of PMGF in spring wheat decreased exponentially with increasing plant population density, but showed no dependence on either crop genotype or height. However, increasing plant densities beyond the recommended planting rate of 300 cropped wheat plants m(-2) provided no obvious benefit to reducing PMGF. Nevertheless, our results demonstrate a critical plant density of 175-200 cropped wheat plants m(-2) below which PMGF frequencies rise exponentially with decreasing plant density. These results will be useful in the development of mechanistic models and best management practices that collectively facilitate the coexistence of transgenic and nontransgenic wheat crops.


Assuntos
Fluxo Gênico , Resistência a Herbicidas , Plantas Geneticamente Modificadas/genética , Triticum/genética , Cruzamentos Genéticos , Pólen/genética , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
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