Advances in Understanding Wheat Grain Color: Genetic, Nutritional, and Agronomic Perspectives

Abstract

Wheat, as a staple crop, holds paramount importance in global food security, and its grain color significantly influences market value, nutritional quality, and consumer preferences. This review critically summarizes recent advances in the genetic basis of wheat grain color, encompassing the biochemical pathways responsible for pigment production and the implications of these traits on nutritional quality. Additionally, we explore the influence of environmental factors on grain color and its prospective role in breeding programs aimed at enhancing the nutritional profile of wheat. Recent findings highlight the growing interest in colored wheat due to its health benefits, further driven by the rise in natural food trends. The review concludes with a discussion on future research directions and the importance of integrated breeding strategies.

1. Introduction

Wheat (Triticum aestivum L.) is one of the most extensively cultivated crops globally, serving as a staple food for billions and a critical source of energy, protein, and dietary fiber [1]. The color of wheat grains plays a significant role in their marketability and consumer preference for various food products. The visual appeal of wheat products not only influences buying decisions but also correlates with perceived nutritional quality [2].

There exists a wide array of grain colors ranging from conventional white to red, purple, and even blue hues, each attributed to the presence of diverse pigments, including flavonoids and carotenoids [3]. Carotenoids are a general term for two major types of pigments: carotenes and xanthophylls [4]. Flavonoids are divided into seven subtypes: anthocyanins, proanthocyanidins, flavonols, flavones, flavanones, isoflavones, and chalcones [5]. These pigments, particularly anthocyanins, have garnered attention for their antioxidant properties and potential health benefits, leading to a resurgence of interest in colored wheat varieties [6,7]. This review focuses on anthocyanins as the main discussion topic.

Anthocyanins in colored wheat have a wide range of biological activities, which are related to antioxidant, anti-inflammatory, antibacterial, and anticancer activities [8]. From a genetic perspective, the fine regulatory mechanism of the anthocyanin biosynthesis pathway has gradually become clear, especially the core regulatory role of the MYB-bHLH-WD40 (MBW) ternary complex. It is worth noting that in addition to structural genes and regulatory genes affecting the biosynthesis of anthocyanins, external environmental factors (light, temperature, hormones, water, fertilization, metal ions) also have a certain influence on the synthesis and regulation of anthocyanins [9,10]. Therefore, current agronomic progress focuses on the regulatory mechanism of environment–gene interactions, and implements comprehensive agriculture that takes environmental variables into consideration to balance the contradiction between pigment accumulation and yield [11]. These advances have expanded the potential of wheat as a functional crop, and can promote nutrition-oriented breeding and innovation in the entire industry chain from “field to table”.

This review aims to consolidate current knowledge on the genetic, biochemical, and environmental factors that influence wheat grain color while discussing implications for breeding practices and potential benefits for health. As consumer awareness of nutrition and health continues to rise, it is essential to provide evidence-based insights into the benefits and challenges associated with colored wheat, thus informing breeding programs and agricultural practices [2,12].

2. Genetic Basis of Wheat Grain Color

Understanding the genetic foundation of grain color in wheat is integral to breeding programs aimed at improving grain quality. Grain color is influenced by specific genes, epistatic interactions, and environmental factors that can affect pigment expression. Advances in molecular genetics are facilitating deeper insights into these genetic mechanisms, enabling more targeted breeding strategies [13].

2.1. Key Genes Associated with Grain Color

The regulation of grain color in wheat is governed by a multitude of genes, particularly transcription factors and structural genes involved in the biosynthesis of flavonoids and other pigments [14].

2.1.1. Transcription Factors

Three transcription factors (TFs) were activated in samples of colored wheat, including the MYC family and the MYB family. All types of colored wheat express MYC and MYB transcription factors or at least one of the two differentially expressed MYCs [15].

Shoeva et al. [16] identified the bHLH-coding gene TaMYC1/TaMYC1.1 (chromosome 2AL), which controls anthocyanin synthesis in wheat pericarp. TaMYB1 has been characterized as a positive regulator of anthocyanin accumulation, the overexpression of which leads to significantly increased levels of this pigment in grains. TaMYB2 is implicated in modulating responses to environmental stimuli, influencing pigment synthesis under varying light conditions. Moreover, studies have indicated that the interaction between TaMYB1 and TaMYB2 can produce a synergistic effect on anthocyanin production, which may vary across wheat genotypes [16,17].

In addition to the allelic variation of TaMYB1, TaMYB2, and their homologous genes related to the change in grain color, the TaMYB family is also a part of the MYB-bHLH-WD40 ternary complex, and participates in the biosynthesis of flavonoids together with the MYC family [18]. Liu et al. [17] reported that in wheat, TaPpm1 (MYB from chromosome 7D) and TaPpb1 (MYC from chromosome 2A) co-regulate anthocyanin production in the purple pericarp.

2.1.2. Additional Genes and Biosynthetic Pathway Components

In addition to the TaMYB genes, other loci play significant roles in grain pigmentation. The CHS gene is crucial for initiating the flavonoid biosynthetic pathway. Variations in CHS can lead to differences in the accumulation of anthocyanins and other flavonoids, subsequently affecting grain color [19]. Mutations and polymorphisms in these genes can translate into lighter grain phenotypes, underscoring their importance in the pigmentation process [18].

The Flavonoid 3′-Hydroxylase (F3′H) gene, which is involved in the hydroxylation of flavonoids, also contributes to the diversity of pigmentation in wheat grains. Different alleles of F3′H can lead to variations in pigment composition, thus affecting the intensity of grain color [14]. Another significant gene is the Colorless gene (c), which acts as a negative regulator of anthocyanin production. Genetic interactions involving the c locus and the purple pigment locus in wheat illustrate the complexity of color modulation. This interplay creates a regulatory network that governs color expression, highlighting the necessity of understanding epistatic relationships within these pathways [16].

In addition to flower pigment biosynthesis, other genes, including HV58, O-methyltransferase ZRP4, Os10g0395400 (involved in anthocyanin transportation in black rice caryopsis), and the MATE outflow family indirectly enhance flower pigment accumulation [20].

2.1.3. Pathway Regulators and Signaling Molecules

Moreover, genes encoding biosynthetic enzymes like Flavanone 3-Hydroxylase (F3H) and Leucoanthocyanidin Dioxygenase (LDOX) play essential roles in the production and diversification of flavonoid compounds that influence grain color [21,22]. These enzymes catalyze specific steps in the flavonoid biosynthetic pathway, and their expression levels can directly impact the concentration of pigments in the grains.

Recent advances in genomics have also identified several Genetic Variants Linked to Phenotypic Traits (GVLPTs), establishing a comprehensive genetic background relevant to grain color. Single Nucleotide Polymorphisms (SNPs) within these genes have been associated with variations in pigmentation and can serve as important molecular markers for breeding programs [23].

2.2. Genomic Approaches and Marker Development

The integration of modern genomic technologies, such as CRISPR/Cas9 and next-generation sequencing (NGS), has revolutionized the genetic mapping of color traits in wheat. These advancements facilitate the identification of key genetic markers associated with desirable traits, enabling more efficient selection processes in breeding programs [23].

2.2.1. Marker-Assisted Selection (MAS)

Marker-assisted selection (MAS) has emerged as a powerful tool to screen for desirable alleles linked to grain pigmentation traits. The successful use of molecular markers, including SNPs and InDels (insertions/deletions), enables breeders to select for specific traits effectively, significantly reducing the time required to develop new varieties. This approach ensures that key alleles associated with enhanced grain color are retained and propagated through generations, enhancing the efficiency of breeding efforts [21].

Near-isogenic lines developed through molecular marker-assisted selection and hybridization methods showed that dominant alleles such as Pp-A1, Pp-D1, and Pp3 acted together to significantly increase the expression of anthocyanin biosynthesis genes CHI and F3H [24].

2.2.2. Genome-Wide Association Studies (GWAS)

Beyond traditional QTL mapping, genome-wide association studies (GWASs) are increasingly being employed to elucidate the genetic basis of grain color. These population-based studies utilize high-density genotyping data to identify associations between genetic markers and phenotypic traits in diverse wheat populations. Insights gained from GWAS have led to the identification of several new loci associated with grain color traits, providing invaluable resources for breeders seeking to enhance anthocyanin levels and overall grain quality [23].

A recent GWAS identified multiple significant SNP associations on chromosomes 3A, 4D, and 6A that are correlated with increased anthocyanin content, illustrating the effectiveness of this approach. The collected data not only advance our understanding of the genetic architecture of grain color but also accelerate the introgression of desirable alleles into commercial varieties [15].

2.2.3. Integration of Omics Technologies in Breeding

The success of genetic tools, such as MAS and GWAS, emphasizes the importance of leveraging genetic diversity within wheat germplasm to foster the development of new cultivars that meet consumer demands and agricultural sustainability goals. The merging of genomics, transcriptomics, proteomics, and metabolomics (collectively termed “multi-omics”) provides a holistic understanding of the complex interactions governing grain color and quality [25,26].

For example, integrating transcriptomic data to identify differentially expressed genes during different developmental stages and environmental conditions can provide clues on how to manipulate these factors for improved pigment production [27]. Furthermore, metabolomic profiling can elucidate the concentration and diversity of bioactive compounds, enabling the identification of cultivars with superior health benefits [26].

2.2.4. Metabolic Engineering

A way of metabolic engineering is to overexpress heterologous regulatory genes or endogenous regulators when available, so choosing the right heterologous regulators is crucial to obtain anthocyanin-rich varieties.

Current research shows that transcription factors regulating anthocyanins share a large conserved functional domain, and functional diversity between a species and closely related species is typically found in regulatory sequences rather than coding regions. This high conservation may help metabolic engineering [21,28].

3. Biochemical Mechanisms of Pigment Production

The biosynthesis of pigments within wheat grains, particularly anthocyanins, requires a complex network of biochemical pathways. These pathways are intricately regulated and can be influenced by both genetic and environmental factors [14,18].

3.1. Biosynthesis Pathway Overview

The production of anthocyanins in wheat grains primarily occurs via the phenylpropanoid pathway. This pathway commences with the conversion of phenylalanine to cinnamic acid by the enzyme phenylalanine ammonia-lyase (PAL), which is the first committed step in flavonoid biosynthesis [29]. Subsequent enzymatic steps lead to the formation of different anthocyanins, resulting in varying grain colors. Key enzymes include Chalcone Synthase (CHS), Chalcone Isomerase (CHI), Flavonoid 3-Hydroxylase (F3H), and Anthocyanin Synthase (ANS), each contributing to specific steps in the anthocyanin biosynthetic pathway [19,25].

Recent transcriptomic and metabolomic studies have elucidated that various environmental conditions can modulate these pathways. For instance, increased light exposure has been found to correlate with enhanced anthocyanin levels, suggesting potential strategies for optimizing growing conditions [26]. The regulatory mechanisms controlling this biosynthesis are complex and involve a network of transcription factors and signaling pathways.

Furthermore, hormones such as abscisic acid (ABA) and gibberellins have been implicated in the regulation of anthocyanin accumulation in response to environmental stresses [30]. Understanding the intricate signaling networks that govern pigment production can guide the development of breeding strategies aimed at enhancing pigmentation in wheat grains.

3.2. Expression and Regulation of Genes Related to Flavonoid Biosynthesis

3.2.1. Structural Genes

The mRNA abundance of most structural genes, such as those encoding cinnamic acid 4-hydroxylase (C4H), flavonoid 3′5′-hydroxylase (F3′5′H), dihydroflavonol 4-reductase (DFR), 4-coumarate CoA ligase (4CL), and UDP-glucose flavonoid 3-oxy-glucosyl transferase (UFGT), strongly correlates with the accumulation of anthocyanin glycosides [18,19].

The structural genes can be divided into the following:

Upstream structural genes (PAL, C4H, and 4CL) regulate the transformation of phenylalanine into 4-coumaroyl-CoA.

Early structural genes (CHS, CHI, and F3H) synthesize dihydrokaempferol from 4-coumaroyl-CoA.

Late structural genes (F3′H, F3′5′H, DFR, ANS, and UFGT) convert dihydrokaempferol into colored anthocyanidins.

In the phenylpropanoid pathway (Figure 1), the coordinated action of these genes ensures the efficient biosynthesis of anthocyanins [14,31].

3.2.2. The MYB-bHLH-WD40 Ternary Complex (MBW)

Regulation of anthocyanin biosynthesis is primarily controlled by the protein complex MYB-bHLH-WD40 (MBW), which binds to the promoters of structural genes and regulates their expression at the transcriptional level, ultimately leading to the accumulation of anthocyanin glycosides [33,34]. However, the MBW complex primarily regulates late structural genes and has little or no effect on early structural genes [22].

Jiang et al. [35] pointed out that WD40 serves as a docking platform to promote the interaction between MYB and bHLH and stabilizes the transcription factor (TF) complexes, but it does not have intrinsic enzymatic functions (DNA-binding or initiating target genes). Hu et al. identified 394 of 743 TaWD40 proteins in wheat and found that WD40 is expressed in wheat seeds regardless of color, highlighting its conserved role in the regulation of anthocyanin biosynthesis [36].

4. Nutritional Quality and Health Implications

The connection between grain color in wheat and nutritional quality is an emerging field of study with vital implications for food security and public health [2].

4.1. The Relationship Between Grain Color and Nutritional Quality

From the origin and evolution of wheat to the modern breeding process, the grains of the current main wheat varieties are mostly white and red in color. However, colored wheat presents special colors such as purple, blue, and black because its grains are rich in anthocyanins, which is a precious germplasm resource for wheat breeding [37]. The anthocyanins of purple wheat are present in the pericarp, the anthocyanins of blue wheat are present in the aleurone layer, and black wheat is mainly obtained by hybridizing purple and blue wheat. The anthocyanins are present in both the pericarp and the aleurone layer [38].

4.1.1. Types of Anthocyanins in Colored Wheat

Cyanidin is the most common anthocyanidin (aglycone) followed by delphinidin, peonidin, pelargonidin, petunidin, and malvidin. They form relatively stable anthocyanins through glycosylation, and the anthocyanin compounds in different parts determine the color of wheat grains. Blue wheat mainly contains delphinidin and cyanidin, purple wheat mainly contains cyanidin, pelargonidin, malvadin, and morning glory pigment, while black wheat is unique to peonydin anthocyanins [39,40].

Beyond aesthetic appeal, the color of wheat grains holds significant nutritional implications. The nutraceutical profile of wheat lines is observed as black > blue > purple > white [41]. Anthocyanins are flavonoid compounds widely studied for their health-promoting properties, and the colored varieties have been shown to contain higher levels of anthocyanins, which have been linked to improved metabolic health through mechanisms such as enhancing lipid profiles and reducing insulin resistance [42].

Moreover, the interactions among anthocyanins, starch digestibility, and food microstructures are vital to clarify the digestion processes of fortified food systems. Such findings have fueled consumer interest in adopting colored grains as part of a healthier lifestyle, prompting further exploration into their agronomic viability and potential impact on food product development [43].

4.1.2. Other Beneficial Compounds in Colored Wheat

In addition to anthocyanins, colored wheat varieties often possess higher levels of beneficial phytochemicals, such as phenolic acids and other antioxidant compounds [44,45]. These nutrients contribute to the health benefits associated with the consumption of whole grains, as they are linked to lower risks of chronic diseases, including cardiovascular conditions and certain cancers [46].

In addition, the amino acids, proteins, vitamins, minerals, dietary fiber, and other nutrients in colored wheat also have great advantages over ordinary wheat, which has a wide range of application value and development prospects as an ideal raw material for nutritional and health food. Ma et al. [47] show that black wheat grains have higher nutritional value, and its mineral elements and protein content are significantly higher than other colored wheat. Guo et al. [48] conclude that the content of zinc, iron, magnesium, and potassium in purple wheat is higher than that of the control white wheat, and purple wheat has a clear advantage in nutritional content over ordinary white wheat.

4.2. Antioxidant Properties and Health Benefits

Anthocyanins and other bioactive compounds present in colored wheat have garnered attention for their potential health benefits. Numerous studies have highlighted the antioxidant properties of these compounds, suggesting that they can mitigate oxidative stress and inflammation within the human body [3,49].

The bioavailability of these compounds plays a crucial role in their effectiveness, and different processing techniques can lead to variations in the retention of anthocyanins, prompting the need for greater understanding in this area [6]. For instance, milling practices that retain bran and germ are likelier to preserve the health-promoting properties of colored wheat [12]. Research indicates that different cooking methods (baking, boiling, etc.) can also affect the bioavailability of anthocyanins, highlighting the need for further studies to optimize processing techniques [13].

The consumption of whole grains, particularly colored varieties, has also been linked to improved glycemic control, supporting weight management and enhancing overall metabolic health. These findings propel the notion that promoting colored wheat in dietary guidelines could influence public health positively [13].

4.3. Market Trends and Consumer Preferences

The changing landscape of consumer preferences is having a significant impact on the wheat market, particularly with respect to colored wheat varieties. As individuals become more health-conscious and mindful about their food choices, many are seeking alternatives that align with their values of natural eating and nutritional benefits [2].

4.3.1. Health Consciousness and Nutritional Awareness

A major driver behind the rising popularity of colored wheat varieties is the growing awareness of their nutritional benefits. Colored wheat, especially varieties rich in anthocyanins and other pigment compounds, is often associated with higher levels of beneficial phytochemicals, such as antioxidants and dietary fiber. These components contribute to various health benefits, including reduced risk of chronic diseases like cardiovascular conditions and certain cancers [46].

In particular, consumers are increasingly drawn to the color of grains as a marker of healthfulness. Research shows that colored varieties, such as red and purple wheat, tend to have higher antioxidant capacities and dietary fiber content compared to conventional white wheat [50]. Such attributes not only enhance consumer perceptions of health benefits but also spur interest in these products as part of a holistic approach to a balanced diet.

4.3.2. Marketing Strategies and Product Innovation

The market dynamics around colored wheat varieties have encouraged both breeders and producers to innovate in developing new food products. This innovation has led to a rise in products derived from colored grains, including breads, pastas, cereals, and snacks that cater to health-oriented consumers [42]. Farmers’ markets and health food stores have become prominent venues for these products, effectively meeting the demand for novel food sources as consumers seek more diversity in their diets.

To enhance the marketability of colored wheat products, effective marketing strategies are essential. Storytelling around the heritage, sustainability, and nutritional benefits of colored wheat can create strong consumer connections. Brands that communicate the health advantages of these grains and their versatile culinary applications are positioned to resonate better with health-conscious consumers [12].

4.3.3. Culinary Versatility and Consumer Engagement

The unique processing characteristics of colored wheat give rise to a corresponding culinary variety, which plays a crucial role in consumer preferences. Engaging consumers by showcasing recipes and cooking methods that highlight the unique flavors and colors of these grains can enhance their appeal [13].

Moreover, consumer engagement through social media platforms and food blogs can amplify the visibility of colored grain products. By leveraging these channels, brands can foster a community around healthy eating, share personal stories related to whole grains, and encourage lifestyle changes that highlight the benefits of incorporating colored wheat into daily diets.

4.3.4. Sustainability and Ethical Considerations

Another facet influencing consumer preferences is sustainability. Many consumers are now making food choices based on environmental impact. The cultivation of colored wheat varieties is often viewed as a more sustainable practice, as these grains can be produced with fewer chemical inputs due to their natural pest-resistant qualities [51].

Additionally, as consumers seek to support local economies and sustainable agricultural practices, the promotion of colored wheat can be positioned as part of broader movements like farm-to-table initiatives [2]. By highlighting local sourcing and sustainable farming practices, producers can attract a consumer base that values ethical food production.

5. Environmental Influences on Grain Color

Environmental conditions are pivotal in determining the color characteristics and quality of wheat grains. Recognizing how these factors interplay can enhance breeding efforts aimed at optimizing grain pigmentation [52].

5.1. Impact of Environmental Variables

Studies indicate that factors such as light intensity, temperature variation, and soil nutrient levels can profoundly affect grain color. For instance, wheat exposed to higher light intensity accumulates more anthocyanins, leading to deeper pigmentation of the grains [29]. Additionally, temperature fluctuations during growth periods have been shown to influence enzymatic activity associated with pigment biosynthesis, with cooler temperatures often enhancing anthocyanin production [6].

The availability of soil nutrients, particularly nitrogen and phosphorus, also plays a significant role [52]. Deficiencies in these nutrients may hinder pigment biosynthesis, resulting in less vibrant grain coloration [1]. Understanding the biochemical pathways that connect nutrient availability with pigment production opens new avenues for practical application in agronomy.

5.2. Agricultural Practices for Optimal Color Development

Incorporating environmental variables to formulate precision cultivation practices and implementing environment-responsive integrated farming systems can significantly enhance grain color expression. For example, optimizing planting times to align with seasonal light patterns could maximize anthocyanin content in crops [30]. Crop management strategies that maximize light exposure during critical growth stages can improve not only color but also overall yield [15].

Fertility management strategies that include balanced fertilization can enhance nutrient uptake, support pigment biosynthesis, and improve grain quality [1]. Furthermore, the exploration of sustainable farming practices, such as cover cropping and biodiversity, can enrich soil fertility and promote healthier crops.

Research into the effects of climate change on wheat cultivation provides further context for this discussion. Increased atmospheric CO₂ levels and shifting climate patterns could both challenge wheat production and provide opportunities to select for more resilient, high-quality colored wheat varieties [2].

6. Implications for Breeding Programs

The insights gained from recent studies on grain color present tremendous opportunities for modern breeding programs. These programs can leverage genetic diversity, modern genomic tools, and enhanced knowledge of environmental influences to develop high-quality colored wheat varieties [12,38].

6.1. Innovative Breeding Techniques

The integration of genomic selection strategies allows breeders to identify and select for the desired traits associated with color and nutritional quality effectively [25]. The emergence of genome editing technologies, such as CRISPR/Cas9, enables precise modifications to key genes responsible for color traits, facilitating the development of novel wheat lines [23]. Such innovations have the potential to decrease the time and resources required in traditional breeding programs while ensuring that selected traits are accurately expressed in resultant cultivars.

The formation of wheat grain color results from the synergistic interplay of genetic, biochemical, nutritional, and environmental factors. This complex regulatory network provides novel insights for improving both grain color and nutritional quality through integrated approaches combining genomics, transcriptomics, and metabolomics. For instance, GWAS can identify QTLs governing color and nutritional traits [23], while transcriptome analysis reveals differentially expressed genes in anthocyanin biosynthesis pathways under varying environmental conditions [27]. Metabolic engineering further enables the selection of optimal heterologous regulators [28]. This multidimensional and coordinated regulatory strategy can overcome the traditional trade-off between yield and nutritional quality in breeding, making designer breeding of nutrient-rich colored wheat a reality. It offers a groundbreaking solution for functional agriculture and precision nutrition.

Furthermore, traditional breeding techniques, combined with modern molecular markers, can help harness genetic alleles that confer both desirable color and agronomic traits [23]. This convergence of methodologies can expedite the breeding process, producing new varieties that meet both market demands and nutritional needs. Multi-trait selection indices incorporating grain color, yield, and nutritional quality can further enhance breeding efficiency and target advancements across multiple traits [12].

6.2. Addressing Challenges in Breeding Programs

Despite the promising advancements in breeding colored wheat, several challenges remain. The genetic linkage between color and yield traits may impose restraints on selection. Higher pigment levels may generally correlate with lower yields due to resource allocation during grain development [25]. Therefore, breeding programs must adopt a holistic approach, considering how to maintain yield without sacrificing color quality.

Consumer acceptance of novel varieties also poses a challenge that must be addressed through education and marketing strategies [12]. Farmers and producers need to be inherently aware of the health benefits colored wheat can offer and the importance of consumer education in promoting these varieties.

The introduction of colored wheat into the commercial market must also be paired with collaborative efforts focusing on product development and promotion. Partnerships among breeders, food processors, and marketing agents will be crucial for successfully integrating these products into retail environments [13]. Developing consumer-friendly products, alongside transparent communication regarding their benefits, will enhance acceptance and market success.

7. Future Research Directions

As the quest for enhanced wheat varieties continues, identifying future research directions is vital. Multi-disciplinary approaches will be essential to drive innovations in the context of climate change, evolving dietary needs, and changing market dynamics [2].

7.1. Understanding Consumer Preferences

Further research is necessary to understand consumer preferences at regional and global levels, especially concerning colored wheat products. Conducting detailed market studies can provide insights into how to position colored wheat while addressing misconceptions regarding taste and health benefits [12]. Understanding the sociocultural values associated with wheat consumption will also promote targeted marketing strategies.

7.2. Holistic Approaches to Breeding

Future breeding initiatives should integrate physiological, genomic, and agrometric data to develop comprehensive breeding programs [15]. Such holistic approaches can enhance the predictability of desired traits, ensuring that colored varieties maintain their nutritional and agronomic superiority amidst environmental variability [7].

Moreover, integrating studies on consumer nutrition, sensory properties, and environmental sustainability will drive further interest in colored wheat cultivation [12]. Collaborative research efforts across universities, agricultural institutions, and industry stakeholders can foster knowledge exchange, resulting in more innovative solutions [2].

8. Conclusions

The exploration of the genetic, biochemical, nutritional, and environmental factors influencing wheat grain color is integral to developing new cultivars that provide enhanced nutritional quality. As the global population continues to grow, the need for diverse, nutrient-rich food sources becomes increasingly urgent. Understanding the synergistic relationship between genetic traits and environmental conditions paves the way for breakthroughs in breeding practices, ultimately contributing to improved food security and public health.

This article found that there is a clear correlation between the “genetics-biochemistry-nutrition-environment” of colored wheat (Figure 2): from genetics to nutrition, anthocyanin synthesis is regulated by the MBW complex, key genes are determined by cascade reactions in the phenylpropanoid pathway, and anthocyanin type and concentration determine grain color and nutritional quality; the environment can affect the genetic basis and nutritional quality of colored wheat, and environmental factors such as light intensity, temperature changes, and soil nutrient levels have a profound impact on grain color. The contradiction between color and yield can be balanced by optimizing cultivation strategies.

Future research should focus on the integration of genetic and agronomic approaches to ensure that colored wheat varieties can meet market demands whilst delivering optimal health benefits. Moreover, continued efforts to promote public awareness around the benefits of consuming whole grains and colored varieties will play a vital role in shaping the market and driving innovation in wheat production.