Status and market potential of transgenic biofortified crops

Belgian dietitians' knowledge, perceptions and willingness-to-recommend of genetically modified food and organisms

BACKGROUND

Dietitians play a critical role in the public's relationship with food and are often overlooked as an important stakeholder group in the general debate about sustainable food. Genetically modified organisms (GMOs) are one type of modern food source that could contribute to a more sustainable food system. This case study is the first to examine the knowledge, perception and willingness-to-recommend (WTR) genetically modified (GM) foods by dietitians in Europe.

METHODS

An online survey was addressed to all members of the Flemish Association of Dietitians (Belgium) in 2021, resulting in a sample of 98 valid responses. Multivariate linear regression included sociodemographic, knowledge, and attitudinal factors as the independent variables to explain dietitians' WTR.

RESULTS

Flemish dietitians had limited knowledge of GMOs; only about half of the GM questions were answered correctly. Most dietitians (53%-76%) would recommend GMOs with positive effects on human nutrition or sustainability, whereas few dietitians (19%-27%) would recommend other GMO applications. Trust in GMO information sources and perceived GM benefits significantly influenced a positive WTR of GM foods. Predominant negative information about GM foods was significantly associated with dietitians' low trust and WTR such foods.

CONCLUSIONS

Countering the predominantly negative portrayal with more neutral and factual information could improve trust, which in turn could positively influence dietitians' perceptions towards GMOs. By further examining the knowledge and perception of dietitians worldwide GMOs and gene-edited products, new insights could be could gathered into the positioning of this underexposed stakeholder group.

The role of orphan crops in the transition to nutritional quality-oriented crop improvement

Micronutrient malnutrition is a persisting problem threatening global human health. Biofortification via metabolic engineering has been proposed as a cost-effective and short-term means to alleviate this burden. There has been a recent rise in the recognition of potential that underutilized, orphan crops can hold in decreasing malnutrition concerns. Here, we illustrate how orphan crops can serve as a medium to provide micronutrients to populations in need, whilst promoting and maintaining dietary diversity. We provide a roadmap, illustrating which aspects to be taken into consideration when evaluating orphan crops. Recent developments have shown successful biofortification via metabolic engineering in staple crops. This review provides guidance in the implementation of these successes to relevant orphan crop species, with a specific focus on the relevant micronutrients iron, zinc, provitamin A and folates.

Breeding and adoption of biofortified crops and their nutritional impact on human health

Micronutrient malnutrition has affected over two billion people worldwide and continues to be a health risk. A growing human population, poverty, and the prevalence of low dietary diversity are jointly responsible for malnutrition, particularly in developing nations. Inadequate bioavailability of key micronutrients, such as iron (Fe), zinc (Zn), and vitamin A, can be improved through agronomic and/or genetic interventions. The Consultative Group on International Agricultural Research prioritizes developing biofortified food crops that are rich in minerals and vitamins through the HarvestPlus initiative on biofortification. The objective of this review is to provide an overview of biofortified food crops along with evidence supporting their acceptability and adoption. Between 2004 and 2019, 242 biofortified varieties belonging to 11 major crops were released in 30 countries across Asia, Africa, and Latin America. These conventionally bred biofortified crops include Fe-enriched beans, pearl millet, and cowpea; Zn-enriched rice, wheat, and maize; both Fe- and Zn-enriched lentil and sorghum; and varieties with improved vitamin A in orange-fleshed sweet potato, maize, cassava, and banana/plantain. In addition to ongoing efforts, breeding innovations, such as speed breeding and CRISPR-based gene editing technologies, will be necessary for the next decade to reach two billion people with biofortified crops.

Advanced biotechnological strategies towards the development of crops with enhanced micronutrient content

Micronutrients are essential mineral elements required for both plant and human development.An integrated system involving soil, climatic conditions, and types of crop plants determines the level of micronutrient acquisition and utilization. Most of the staple food crops consumed globally predominantly include the cereal grains, tubers and roots, respectively and in many cases, particularly in the resource-poor countries they are grown in nutrient-deficient soils. These situations frequently lead to micronutrient deficiency in crops. Moreover, crop plants with micronutrient deficiency also show high level of susceptibility to various abiotic and biotic stress factors. Apart from this, climate change and soil pollution severely affect the accumulation of micronutrients, such as zinc (Zn), iron (Fe), selenium (Se), manganese (Mn), and copper (Cu) in food crops. Therefore, overcoming the issue of micronutrient deficiency in staple crops and to achieve the adequate level of food production with enriched nutrient value is one of the major global challenges at present. Conventional breeding approaches are not adequate to feed the increasing global population with nutrient-rich staple food crops. To address these issues, alongside traditional approaches, genetic modification strategies have been adopted during the past couple of years in order to enhance the transport, production, enrichment and bioavailability of micronutrients in staple crops. Recent advances in agricultural biotechnology and genome editing approaches have shown promising response in the development of micronutrient enriched biofortified crops. This review highlights the current advancement of our knowledge on the possible implications of various biotechnological tools for the enrichment and enhancement of bioavailability of micronutrients in crops.

A genome-wide association study of folates in sweet corn kernels

Folate is commonly synthesized in natural plants and is an essential water-soluble vitamin of great importance inhuman health. Although the key genes involved in folate biosynthesis and transformation pathways have been identified in plants, the genetic architecture of folate in sweet corn kernels remain largely unclear. In this study, an association panel of 295 inbred lines of sweet corn was constructed. Six folate derivatives were quantified in sweet corn kernels at 20 days after pollination and a total of 95 loci were identified for eight folate traits using a genome-wide association study. A peak GWAS signal revealed that natural variation in ZmFCL, encoding a 5-formyltetrahydrofolate cyclo-ligase, accounted for 30.12% of phenotypic variation in 5-FTHF content. Further analysis revealed that two adjacent SNPs on the second exon resulting in an AA-to-GG in the gene and an Asn-to-Gly change in the protein could be the causative variant influencing 5-FTHF content. Meanwhile, 5-FTHF content was negatively correlated with ZmFCL expression levels in the population. These results extend our knowledge regarding the genetic basis of folate and provide molecular markers for the optimization of folate levels in sweet corn kernels.

The future of CRISPR gene editing according to plant scientists

This study surveyed 669 plant scientists globally to elicit how (which outcomes of gene editing), where (which continent) and what (which crops) are most likely to benefit from CRISPR research and if there is a consensus about specific barriers to commercial adoption in agriculture. Further, we disaggregated public and private plant scientists to see if there was heterogeneity in their views of the future of CRISPR research. Our findings suggest that maize and soybeans are anticipated to benefit the most from CRISPR technology with fungus and virus resistance the most common vehicle for its implementation. Across the board, plant scientists viewed consumer perception/knowledge gap to be the most impeding barrier of CRISPR adoption. Although CRISPR has been hailed as a technology that can help alleviate food insecurity and improve agricultural sustainability, our study has shown that plant scientists believe there are some large concerns about the consumer perceptions of CRISPR.

Rice carotenoid biofortification and yield improvement conferred by endosperm-specific overexpression of OsGLK1

Carotenoids, indispensable isoprenoid phytonutrients, are synthesized in plastids and are known to be deficient in rice endosperm. Many studies, involving transgenic manipulations of carotenoid biosynthetic genes, have been performed to obtain carotenoid-enriched rice grains. Nuclear-encoded GOLDEN2-LIKE (GLK) transcription factors play important roles in the regulation of plastid and thylakoid grana development. Here, we show that endosperm-specific overexpression of rice GLK1 gene (OsGLK1) leads to enhanced carotenoid production, increased grain yield, but deteriorated grain quality in rice. Subsequently, we performed the bioengineering of carotenoids biosynthesis in rice endosperm by introducing other three carotenogenic genes, tHMG1, ZmPSY1, and PaCrtI, which encode the enzymes truncated 3-hydroxy-3-methylglutaryl-CoA reductase, phytoene synthase, and phytoene desaturase, respectively. Transgenic overexpression of all four genes (OsGLK1, tHMG1, ZmPSY1, and PaCrtI) driven by rice endosperm-specific promoter GluB-1 established a mini carotenoid biosynthetic pathway in the endosperm and exerted a roughly multiplicative effect on the carotenoid accumulation as compared with the overexpression of only three genes (tHMG1, ZmPSY1, and PaCrtI). In addition, the yield enhancement and quality reduction traits were also present in the transgenic rice overexpressing the selected four genes. Our results revealed that OsGLK1 confers favorable characters in rice endosperm and could help to refine strategies for the carotenoid and other plastid-synthesized micronutrient fortification in bioengineered plants.

From Golden Rice to Golden Diets: How to turn its recent approval into practice

Following its approval in the Philippines in July 2021, provitamin A-rich "Golden Rice" is set to become the worlds' first commercialized genetically modified crop with direct consumer benefits. Despite supplementation and fortification programs, the burden of micronutrient deficiencies remains high. For Golden Rice to be successful in reducing vitamin A deficiency, it needs to be taken up by food systems and integrated into consumer diets. Despite negative information often being associated with genetic engineering, evidence suggests that consumers react positively to Golden Rice. Thus, it offers policy makers and public health stakeholders a new, powerful option to address micronutrient malnutrition that they can integrate as a cost-effective component in broader nutrition strategies and tailor it to consumers' heterogeneous socio-economic contexts and needs to promote "Golden Diets". For this to happen, the right framing of the pathway from policy to consumption is crucial.

Metabolic engineering provides insight into the regulation of thiamin biosynthesis in plants

Thiamin (or thiamine) is a water-soluble B-vitamin (B1), which is required, in the form of thiamin pyrophosphate, as an essential cofactor in crucial carbon metabolism reactions in all forms of life. To ensure adequate metabolic functioning, humans rely on a sufficient dietary supply of thiamin. Increasing thiamin levels in plants via metabolic engineering is a powerful strategy to alleviate vitamin B1 malnutrition and thus improve global human health. These engineering strategies rely on comprehensive knowledge of plant thiamin metabolism and its regulation. Here, multiple metabolic engineering strategies were examined in the model plant Arabidopsis thaliana. This was achieved by constitutive overexpression of the three biosynthesis genes responsible for B1 synthesis, HMP-P synthase (THIC), HET-P synthase (THI1), and HMP-P kinase/TMP pyrophosphorylase (TH1), either separate or in combination. By monitoring the levels of thiamin, its phosphorylated entities, and its biosynthetic intermediates, we gained insight into the effect of either strategy on thiamin biosynthesis. Moreover, expression analysis of thiamin biosynthesis genes showed the plant's intriguing ability to respond to alterations in the pathway. Overall, we revealed the necessity to balance the pyrimidine and thiazole branches of thiamin biosynthesis and assessed its biosynthetic intermediates. Furthermore, the accumulation of nonphosphorylated intermediates demonstrated the inefficiency of endogenous thiamin salvage mechanisms. These results serve as guidelines in the development of novel thiamin metabolic engineering strategies.

Development and validation of breeder-friendly gene-based markers for lpa1-1 and lpa2-1 genes conferring low phytic acid in maize kernel

Based on C (wild) to T (mutant) transition at amino acid position 1432 bp of lpa1-1 gene, two dominant markers each specific to wild type (LPA1) and mutant (lpa1-1) allele were developed and validated across seven F₂ populations. Joint segregation of these markers behaved in co-dominant fashion, clearly distinguishing heterozygote from two other homozygote genotypes. Full length sequence alignment between wild type (LPA2) and mutant (lpa2-1) allele revealed one transition mutation (A to G) and a co-dominant CAPS marker was developed which differentiated all three types of segregants across seven F₂ populations. Across populations, segregants with lpa1-1/lpa1-1 (1.77 mg/g) and lpa2-1/lpa2-1 (1.85 mg/g) possessed significantly lower phytic acid compared to LPA1/LPA1 (2.58 mg/g) and LPA2/LPA2 (2.53 mg/g). Inorganic phosphorus was however higher in recessive homozygotes (lpa1-1/lpa1-1: 0.77 mg/g, lpa2-1/lpa2-1: 0.53 mg/g) than the dominant homozygotes (LPA1/LPA1: 0.33 mg/g, LPA2/LPA2: 0.19 mg/g). Overall, homozygous segregants of lpa1-1 and lpa2-1 showed 31% and 27% reduction of phytic acid, respectively. Analysis of phytate and inorganic phosphorous in the maize kernel in these segregating populations confirmed co-segregation of trait and markers specific to lpa1-1 and lpa2-1. This is the first report of the development of breeder-friendly gene-based markers for lpa1-1 and lpa2-1; and it holds great significance for maize biofortification.

Crystal structure of plant vacuolar iron transporter VIT1

The iron ion is an essential cofactor in several vital enzymatic reactions, such as DNA replication, oxygen transport, and respiratory and photosynthetic electron transfer chains, but its excess accumulation induces oxidative stress in cells. Vacuolar iron transporter 1 (VIT1) is important for iron homeostasis in plants, by transporting cytoplasmic ferrous ions into vacuoles. Modification of the VIT1 gene leads to increased iron content in crops, which could be used for the treatment of human iron deficiency diseases. Furthermore, a VIT1 from the malaria-causing parasite Plasmodium is considered as a potential drug target for malaria. Here we report the crystal structure of VIT1 from rose gum Eucalyptus grandis, which probably functions as a H⁺-dependent antiporter for Fe²⁺ and other transition metal ions. VIT1 adopts a novel protein fold forming a dimer of five membrane-spanning domains, with an ion-translocating pathway constituted by the conserved methionine and carboxylate residues at the dimer interface. The second transmembrane helix protrudes from the lipid membrane by about 40 Å and connects to a three-helical bundle, triangular cytoplasmic domain, which binds to the substrate metal ions and stabilizes their soluble form, thus playing an essential role in their transport. These mechanistic insights will provide useful information for the further design of genetically modified crops and the development of anti-malaria drugs.

From in planta Function to Vitamin-Rich Food Crops: The ACE of Biofortification

Humans are highly dependent on plants to reach their dietary requirements, as plant products contribute both to energy and essential nutrients. For many decades, plant breeders have been able to gradually increase yields of several staple crops, thereby alleviating nutritional needs with varying degrees of success. However, many staple crops such as rice, wheat and corn, although delivering sufficient calories, fail to satisfy micronutrient demands, causing the so called 'hidden hunger.' Biofortification, the process of augmenting nutritional quality of food through the use of agricultural methodologies, is a pivotal asset in the fight against micronutrient malnutrition, mainly due to vitamin and mineral deficiencies. Several technical advances have led to recent breakthroughs. Nutritional genomics has come to fruition based on marker-assisted breeding enabling rapid identification of micronutrient related quantitative trait loci (QTL) in the germplasm of interest. As a complement to these breeding techniques, metabolic engineering approaches, relying on a continuously growing fundamental knowledge of plant metabolism, are able to overcome some of the inevitable pitfalls of breeding. Alteration of micronutrient levels does also require fundamental knowledge about their role and influence on plant growth and development. This review focuses on our knowledge about provitamin A (beta-carotene), vitamin C (ascorbate) and the vitamin E group (tocochromanols). We begin by providing an overview of the functions of these vitamins in planta, followed by highlighting some of the achievements in the nutritional enhancement of food crops via conventional breeding and genetic modification, concluding with an evaluation of the need for such biofortification interventions. The review further elaborates on the vast potential of creating nutritionally enhanced crops through multi-pathway engineering and the synergistic potential of conventional breeding in combination with genetic engineering, including the impact of novel genome editing technologies.

From Golden Rice to aSTARice: Bioengineering Astaxanthin Biosynthesis in Rice Endosperm

Carotenoids are important phytonutrients with antioxidant properties, and are widely used in foods and feedstuffs as supplements. Astaxanthin, a red-colored ketocarotenoid, has strong antioxidant activity and thus can benefit human health. However, astaxanthin is not produced in most higher plants. Here we report the bioengineering of astaxanthin biosynthesis in rice endosperm by introducing four synthetic genes, sZmPSY1, sPaCrtI, sCrBKT, and sHpBHY, which encode the enzymes phytoene synthase, phytoene desaturase, β-carotene ketolase, and β-carotene hydroxylase, respectively. Transgneic overexpression of two (sZmPSY1 and sPaCrtI), three (sZmPSY1, sPaCrtI and sCrBKT), and all these four genes driven by rice endosperm-specific promoters established the carotenoid/ketocarotenoid/astaxanthin biosynthetic pathways in the endosperm and thus resulted in various types of germplasm, from the yellow-grained β-carotene-enriched Golden Rice to orange-red-grained Canthaxanthin Rice and Astaxanthin Rice, respectively. Grains of Astaxanthin Rice were enriched with astaxanthin in the endosperm and had higher antioxidant activity. These results proved that introduction of a minimal set of four transgenes enables de novo biosynthesis of astaxanthin in the rice endosperm. This work provides a successful example for synthetic biology in plants and biofortification in crops; the biofortified rice products generated by this study could be consumed as health-promoting foods and processed to produce dietary supplements.

Toward Eradication of B-Vitamin Deficiencies: Considerations for Crop Biofortification

'Hidden hunger' involves insufficient intake of micronutrients and is estimated to affect over two billion people on a global scale. Malnutrition of vitamins and minerals is known to cause an alarming number of casualties, even in the developed world. Many staple crops, although serving as the main dietary component for large population groups, deliver inadequate amounts of micronutrients. Biofortification, the augmentation of natural micronutrient levels in crop products through breeding or genetic engineering, is a pivotal tool in the fight against micronutrient malnutrition (MNM). Although these approaches have shown to be successful in several species, a more extensive knowledge of plant metabolism and function of these micronutrients is required to refine and improve biofortification strategies. This review focuses on the relevant B-vitamins (B1, B6, and B9). First, the role of these vitamins in plant physiology is elaborated, as well their biosynthesis. Second, the rationale behind vitamin biofortification is illustrated in view of pathophysiology and epidemiology of the deficiency. Furthermore, advances in biofortification, via metabolic engineering or breeding, are presented. Finally, considerations on B-vitamin multi-biofortified crops are raised, comprising the possible interplay of these vitamins in planta.

Folate Biofortification of Potato by Tuber-Specific Expression of Four Folate Biosynthesis Genes

Insufficient dietary intake of micronutrients, known as "hidden hunger", is a devastating global burden, affecting two billion people. Deficiency of folates (vitamin B9), which are known to play a central role in C₁ metabolism, causes birth defects in at least a quarter million people annually. Biofortification to enhance the level of naturally occurring folates in crop plants, proves to be an efficient and cost-effective tool in fighting folate deficiency. Previously, introduction of folate biosynthesis genes GTPCHI and ADCS, proven to be a successful biofortification strategy in rice and tomato, turned out to be insufficient to adequately increase folate levels in potato tubers. Here, we provide a proof of concept that additional introduction of HPPK/DHPS and/or FPGS, downstream genes in mitochondrial folate biosynthesis, enables augmentation of folates to satisfactory levels (12-fold) and ensures folate stability upon long-term storage of tubers. In conclusion, this engineering strategy can serve as a model in the creation of folate-accumulating potato cultivars, readily applicable in potato-consuming populations suffering from folate deficiency.

Development of "Purple Endosperm Rice" by Engineering Anthocyanin Biosynthesis in the Endosperm with a High-Efficiency Transgene Stacking System

Anthocyanins have high antioxidant activities, and engineering of anthocyanin biosynthesis in staple crops, such as rice (Oryza sativa L.), could provide health-promoting foods for improving human health. However, engineering metabolic pathways for biofortification remains difficult, and previous attempts to engineer anthocyanin production in rice endosperm failed because of the sophisticated genetic regulatory network of its biosynthetic pathway. In this study, we developed a high-efficiency vector system for transgene stacking and used it to engineer anthocyanin biosynthesis in rice endosperm. We made a construct containing eight anthocyanin-related genes (two regulatory genes from maize and six structural genes from Coleus) driven by the endosperm-specific promoters,plus a selectable marker and a gene for marker excision. Transformation of rice with this construct generated a novel biofortified germplasm "Purple Endosperm Rice" (called "Zijingmi" in Chinese), which has high anthocyanin contents and antioxidant activity in the endosperm. This anthocyanin production results from expression of the transgenes and the resulting activation (or enhancement) of expression of 13 endogenous anthocyanin biosynthesis genes that are silenced or expressed at low levels in wild-type rice endosperm. This study provides an efficient, versatile toolkit for transgene stacking and demonstrates its use for successful engineering of a sophisticated biological pathway, suggesting the potential utility of this toolkit for synthetic biology and improvement of agronomic traits in plants.

The social and economic impact of biofortification through genetic modification

Genetic modification (GM) has been advocated as an alternative or complement to micronutrient interventions such as supplementation, fortification or dietary diversification. While proof-of-concept of various GM biofortified crops looks promising, the decision tree of policy makers is much more complex, and requires insight on their socio-economic impacts: Will it actually work? Is it financially sound? Will people accept it? Can it be implemented in a globalized world? This review shows that GM biofortification could effectively reduce the burden of micronutrient deficiencies, in an economically viable way, and is generally well received by target beneficiaries, despite some resistance and uncertainty. Practically, however, protectionist and/or unscientific regulations in some developed countries raise the (perceived) bar for implementation in target countries.

Staple crops biofortified with increased vitamins and minerals: considerations for a public health strategy

Biofortification of staple crops has been proposed as a strategy to address micronutrient malnutrition, particularly with respect to insufficient intake of vitamin A, iron, zinc, and folate. The World Health Organization, in collaboration with the Food and Agriculture Organization of the United Nations and the Sackler Institute for Nutrition Science at the New York Academy of Sciences, convened a technical consultation entitled "Staple Crops Biofortified with Vitamins and Minerals: Considerations for a Public Health Strategy" in April 2016. Participants of the consultation reviewed the definition of biofortification of staple crops, patterns of crops production, processing, consumption, seed varieties, and micronutrient stability and bioavailability, as well as farmers' adoption and acceptability of the modified crops. Also discussed were economic, environmental, safety, and equity aspects of biofortified crops, as well as legal, policy, regulatory, and ethical issues for the implementation of biofortification strategies in agriculture and nutrition. Consultation working groups identified important and emerging technical issues, lessons learned, and research priorities to better support the evidence of improved nutrition and unintended adverse effects of biofortification. This paper provides the background and rationale of the technical consultation, synopsizes the presentations, and provides a summary of the main considerations proposed by the working groups.

Methods matter: a meta-regression on the determinants of willingness-to-pay studies on biofortified foods

Following the growing evidence on biofortification as a cost-effective micronutrient strategy, various researchers have elicited consumers' willingness to pay (WTP) for biofortified crops in an effort to justify and determine their adoption. This review presents a meta-analysis of WTP studies on biofortified foods, either developed through conventional breeding or using genetic modification technology. On the basis of 122 estimates from 23 studies (9507 respondents), consumers are generally willing to pay 21.3% more for biofortified crops. Because WTP estimates are often determined through different valuation methods and procedures, a meta-regression was carried out to examine the role of potential determinants. Aside from contextual factors, such as type of food crop, target nutrient, and region (but not breeding technique), various methodological factors significantly influence premiums, including the type of respondent, nature of the study, study environment, participation fee, and provided information. The findings allow researchers to better anticipate potential methodological biases when examining WTP for (biofortified) foods, while it gives policy makers a broad understanding of the potential demand for different biofortified crops in various settings.

The socioeconomics of genetically modified biofortified crops: a systematic review and meta-analysis

Building upon the growing interest and research on genetically modified (GM) biofortification, its socioeconomic potential has been increasingly examined. We conducted two systematic reviews and meta-analyses to provide comprehensive evidence of consumers' willingness to pay (11 economic valuation studies, 64 estimates) and cost-effectiveness/benefits (five economic evaluation studies, 30 estimates). Worldwide, consumers were willing to pay 23.9% more for GM biofortified food crops. Aside from crop and design-related differences, information provision was deemed crucial. Positive information (nutrition and GM benefits) is associated with the highest consumer willingness to pay, compared with negative, objective, and conflicting GM information, especially when negative information was mentioned last. This health intervention would reduce the aggregated micronutrient deficiency burden in Asia (15.6 million disability-adjusted life years (DALYs)) by 12.5-51.4%, at a low cost of USD 7.9-27.8 per DALY in a pessimistic and optimistic scenario, respectively. Given that GM biofortified crops could tackle hidden hunger in a cost-effective and well-accepted way, its implementation is worth pursuing. A case study on folate biofortification further elaborates on the importance of socioeconomic research and the determinants of their market potential.

Globalisation of agrifood systems and sustainable nutrition

The globalisation of agrifood systems is a mega-trend with potentially profound nutritional implications. This paper describes various facets of this globalisation process and reviews studies on nutritional effects with a particular focus on developing countries. Results show that global trade and technological change in agriculture have substantially improved food security in recent decades, although intensified production systems have also contributed to environmental problems in some regions. New agricultural technologies and policies need to place more emphasis on promoting dietary diversity and reducing environmental externalities. Globalising agrifood systems also involve changing supply-chain structures, with a rapid rise of modern retailing, new food safety and food quality standards, and higher levels of vertical integration. Studies show that emerging high-value supply chains can contribute to income growth in the small farm sector and improved access to food for rural and urban populations. However, there is also evidence that the retail revolution in developing countries, with its growing role of supermarkets and processed foods, can contribute to overweight and obesity among consumers. The multi-faceted linkages between changing agrifood systems and nutrition are a new field of interdisciplinary research, combining agricultural, nutritional, economics and social sciences perspectives. The number of studies on specific aspects is still limited, so the evidence is not yet conclusive. A review at this early stage can help to better understand important relationships and encourage follow-up work.

A novel framework for analysing stakeholder interest in healthy foods: A case study on iodine biofortification

Despite the availability of novel strategies to prevent micronutrient malnutrition, such as biofortification, limited understanding of stakeholders often hampers their success. We build upon the existing literature on protection motivations (PMT) and technology acceptance (TAM) to develop an integrated PMTAM model for analyzing stakeholders' reactions, on both the supply and demand sides. Regarding the latter, the case of the iodine biofortified food chain is used to evaluate African households' interest. All model constructs, and threat appraisal in particular, are decisive in determining the uptake of biofortification, while also social demographics and own nutrition status play an important role.

Are all GMOs the same? Consumer acceptance of cisgenic rice in India

India has more than 215 million food-insecure people, many of whom are farmers. Genetically modified (GM) crops have the potential to alleviate this problem by increasing food supplies and strengthening farmer livelihoods. For this to occur, two factors are critical: (i) a change in the regulatory status of GM crops, and (ii) consumer acceptance of GM foods. There are generally two classifications of GM crops based on how they are bred: cisgenically bred, containing only DNA sequences from sexually compatible organisms; and transgenically bred, including DNA sequences from sexually incompatible organisms. Consumers may view cisgenic foods as more natural than those produced via transgenesis, thus influencing consumer acceptance. This premise was the catalyst for our study--would Indian consumers accept cisgenically bred rice and if so, how would they value cisgenics compared to conventionally bred rice, GM-labelled rice and 'no fungicide' rice? In this willingness-to-pay study, respondents did not view cisgenic and GM rice differently. However, participants were willing-to-pay a premium for any aforementioned rice with a 'no fungicide' attribute, which cisgenics and GM could provide. Although not significantly different (P = 0.16), 76% and 73% of respondents stated a willingness-to-consume GM and cisgenic foods, respectively.

Modelling protection behaviour towards micronutrient deficiencies: Case of iodine biofortified vegetable legumes as health intervention for school-going children

BACKGROUND/OBJECTIVES

Despite successes recorded in combating iodine deficiency, more than 2 billion people are still at risk of iodine deficiency disorders. Rural landlocked and mountainous areas of developing countries are the hardest hit, hence the need to explore and advance novel strategies such as biofortification.

SUBJECTS/METHODS

We evaluated adoption, purchase, and consumption of iodine biofortified vegetable legumes (IBVL) using the theory of protection motivations (PMT) integrated with an economic valuation technique. A total of 1,200 participants from three land-locked locations in East Africa were recruited via multi-stage cluster sampling, and data were collected using two, slightly distinct, questionnaires incorporating PMT constructs. The survey also elicited preferences for iodine biofortified foods when offered at a premium or discount. Determinants of protection motivations and preferences for iodine biofortified foods were assessed using path analysis modelling and two-limit Tobit regression, respectively.

RESULTS

Knowledge of iodine, iodine-health link, salt iodization, and biofortification was very low, albeit lower at the household level. Iodine and biofortification were not recognized as nutrient and novel approaches, respectively. On the other hand, severity, fear, occupation, knowledge, iodine status, household composition, and self-efficacy predicted the intention to consume biofortified foods at the household level; only vulnerability, self-efficacy, and location were the most crucial elements at the school level. In addition, results demonstrated a positive willingness-to-pay a premium or acceptance of a lesser discount for biofortification. Furthermore, preference towards iodine biofortified foods was a function of protection motivations, severity, vulnerability, fear, response efficacy, response cost, knowledge, iodine status, gender, age. and household head.

CONCLUSIONS

Results lend support for prevention of iodine deficiency in unprotected populations through biofortification; however 'threat' appraisal and socio-economic predictors are decisive in designing nutrition interventions and stimulating uptake of biofortification. In principle, the contribution is threefold: 1) Successful application of the integrated model to guide policy formulation; 2) Offer guidance to stakeholders to identify and tap niche markets; 3) stimulation of rural economic growth around school feeding programmes.

Overexpression of Arabidopsis VIT1 increases accumulation of iron in cassava roots and stems

Iron is extremely abundant in the soil, but its uptake in plants is limited due to low solubility in neutral or alkaline soils. Plants can rely on rhizosphere acidification to increase iron solubility. AtVIT1 was previously found to be involved in mediating vacuolar sequestration of iron, which indicates a potential application for iron biofortification in crop plants. Here, we have overexpressed AtVIT1 in the starchy root crop cassava using a patatin promoter. Under greenhouse conditions, iron levels in mature cassava storage roots showed 3-4 times higher values when compared with wild-type plants. Significantly, the expression of AtVIT1 showed a positive correlation with the increase in iron concentration of storage roots. Conversely, young leaves of AtVIT1 transgenic plants exhibit characteristics of iron deficiency such as interveinal chlorosis of leaves (yellowing) and lower iron concentration when compared with the wild type plants. Interestingly, the AtVIT1 transgenic plants showed 4 and 16 times higher values of iron concentration in the young stem and stem base tissues, respectively. AtVIT1 transgenic plants also showed 2-4 times higher values of iron content when compared with wild-type plants, with altered partitioning of iron between source and sink tissues. These results demonstrate vacuolar iron sequestration as a viable transgenic strategy to biofortify crops and to help eliminate micronutrient malnutrition in at-risk human populations.

Public Acceptance of Plant Biotechnology and GM Crops

A wide gap exists between the rapid acceptance of genetically modified (GM) crops for cultivation by farmers in many countries and in the global markets for food and feed, and the often-limited acceptance by consumers. This review contrasts the advances of practical applications of agricultural biotechnology with the divergent paths-also affecting the development of virus resistant transgenic crops-of political and regulatory frameworks for GM crops and food in different parts of the world. These have also shaped the different opinions of consumers. Important factors influencing consumer's attitudes are the perception of risks and benefits, knowledge and trust, and personal values. Recent political and societal developments show a hardening of the negative environment for agricultural biotechnology in Europe, a growing discussion-including calls for labeling of GM food-in the USA, and a careful development in China towards a possible authorization of GM rice that takes the societal discussions into account. New breeding techniques address some consumers' concerns with transgenic crops, but it is not clear yet how consumers' attitudes towards them will develop. Discussions about agriculture would be more productive, if they would focus less on technologies, but on common aims and underlying values.

Nutritionally enhanced food crops; progress and perspectives

Great progress has been made over the past decade with respect to the application of biotechnology to generate nutritionally improved food crops. Biofortified staple crops such as rice, maize and wheat harboring essential micronutrients to benefit the world's poor are under development as well as new varieties of crops which have the ability to combat chronic disease. This review discusses the improvement of the nutritional status of crops to make a positive impact on global human health. Several examples of nutritionally enhanced crops which have been developed using biotechnological approaches will be discussed. These range from biofortified crops to crops with novel abilities to fight disease. The review concludes with a discussion of hurdles faced with respect to public perception, as well as directions of future research and development for nutritionally enhanced food crops.