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Zinc (Zn) plays a crucial role in metabolism in both plant and animal life. Zn deficiency is a worldwide problem that has recently gotten worse. This micronutrient shortage can be largely attributed to eating foods that are poor in zinc. If biofortification methods were widely used, Zn enrichment of the organ or tissue of interest would increase dramatically. However, Zn absorption mechanisms in rice plants must be understood on a fundamental level before these methods can be used effectively. Plant systems' Zn transporters and metal chelators play a major role in regulating this intricate physiological characteristic. The Zn efficiency of specific species is affected by a variety of factors, including the plant's growth stage, edaphic conditions, the time of year, and more. Both old and new ways of breeding plants can be used for biofortification. We have highlighted the significance of recombinant and genetic approaches to biofortifying in rice. In this review, we have the metabolic role of zinc in rice, and the different transporter families involved in the transportation of zinc in rice. We have also discussed the combined approaches of agronomic and genetic in zinc biofortification in rice and potential outcomes and future predictions.

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Cassava (Manihot esculenta Crantz) was introduced to Southeast Asia in the 16th-17th centuries and has since flourished as an industrial crop. Since the 1980s, Thailand has emerged as the leading producer and exporter of cassava products. This growth coincided with the initiation of cassava breeding programs in collaboration with the International Center for Tropical Agriculture (CIAT), focusing on root yield and starch production. The success of Thai cassava breeding programs can be attributed to the incorporation of valuable genetic diversity from international germplasm resources to cross with the local landraces, which has become the genetic foundation of many Thai commercial varieties. Effective evaluation under diverse environmental conditions has led to the release of varieties with high yield stability. A notable success is the development of Kasetsart 50. However, extreme climate change poses significant challenges, including abiotic and biotic stresses that threaten cassava root yield and starch content, leading to a potential decline in starch-based industries. Future directions for cassava breeding must include hybrid development, marker-assisted recurrent breeding, and gene editing, along with high-throughput phenotyping and flower induction. These strategies are essential to achieve breeding objectives focused on drought tolerance and disease resistance, especially for CMD and CBSD.

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Malnutrition, often termed "hidden hunger," represents a pervasive global issue carrying significant implications for health, development, and socioeconomic conditions. Addressing the challenge of inadequate essential nutrients, despite sufficient caloric intake, is crucial. Biofortification emerges as a promising solution by enhance the presence of vital nutrients like iron, zinc, iodine, and vitamin A in edible parts of different crop plants. Crop biofortification can be attained through either agronomic methods or genetic breeding techniques. Agronomic strategies for biofortification encompass the application of mineral fertilizers through foliar or soil methods, as well as leveraging microbe-mediated mechanisms to enhance nutrient uptake. On the other hand, genetic biofortification involves the strategic crossing of plants to achieve a desired combination of genes, promoting balanced nutrient uptake and bioavailability. Additionally, genetic biofortification encompasses innovative methods such as speed breeding, transgenic approaches, genome editing techniques, and integrated omics approaches. These diverse strategies collectively contribute to enhancing the nutritional profile of crops. This review highlights the above-said genetic biofortification strategies and it also covers the aspect of reduction in antinutritional components in food through genetic biofortification.

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Traditional crop breeding techniques are not quickly boosting yields to fulfill the expanding population needs. Long crop lifespans hinder the ability of plant breeding to develop superior crop varieties. Due to the arduous crossing, selecting, and challenging processes, it can take decades to establish new varieties with desired agronomic traits. Develop new plant varieties instantly to reduce hunger and improve food security. As a result of the adoption of conventional agricultural techniques, crop genetic diversity has decreased over time. Several traditional and molecular techniques, such as genetic selection, mutant breeding, somaclonal variation, genome-wide association studies, and others, have improved agronomic traits associated with agricultural plant productivity, quality, and resistance to biotic and abiotic stresses. In addition, modern genome editing approaches based on programmable nucleases, CRISPR, and Cas9 proteins have escorted an exciting new era of plant breeding. Plant breeders and scientists worldwide rely on cutting-edge techniques like quick breeding, genome editing tools, and high-throughput phenotyping to boost crop breeding output. This review compiles discoveries in numerous areas of crop breeding, such as using genome editing tools to accelerate the breeding process and create yearly crop generations with the desired features, to describe the shift from conventional to modern plant breeding techniques.

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Plant breeding has made a significant contribution to increasing agricultural production. Conventional breeding based on phenotypic selection is not effective for crop improvement. Because phenotype is considerably influenced by environmental factors, which will affect the selection of breeding materials for crop improvement. The past two decades have seen tremendous progress in plant breeding research. Especially the availability of high-throughput molecular markers followed by genomic-assisted approaches significantly contributed to advancing plant breeding. Integration of speed breeding with genomic and phenomic facilities allowed rapid quantitative trait loci (QTL)/gene identifications and ultimately accelerated crop improvement programs. The advances in sequencing technology helps to understand the genome organization of many crops and helped with genomic selection in crop breeding. Plant breeding has gradually changed from phenotype-to-genotype-based to genotype-to-phenotype-based selection. High-throughput phenomic platforms have played a significant role in the modern breeding program and are considered an essential part of precision breeding. In this review, we discuss the rapid advance in plant breeding technology for efficient crop improvements and provide details on various approaches/platforms that are helpful for crop improvement. This review will help researchers understand the recent developments in crop breeding and improvements.

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S-adenosyl-l-methionine (SAM) is ubiquitous in living organisms and plays important roles in transmethylation, transsulfuration and transamination in organisms. Due to its important physiological functions, production of SAM has attracted increasing attentions. Currently, researches on SAM production mainly focus on microbial fermentation, which is more cost-effective than that of the chemical synthesis and the enzyme catalysis, thus easier to achieve commercial production. With the rapid growth in SAM demand, interests in improving SAM production by developing SAM hyper-producing microorganisms aroused. The main strategies for improving SAM productivity of microorganisms include conventional breeding and metabolic engineering. This review summarizes the recent research progress in improving microbial SAM productivity to facilitate further improving SAM productivity. The bottlenecks in SAM biosynthesis and the solutions were also addressed.

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Chickpea is an important leguminous crop with potential to provide dietary proteins to both humans and animals. It also ameliorates soil nitrogen through biological nitrogen fixation. The crop is affected by an array of biotic and abiotic factors. Among different biotic stresses, a major fungal disease called Fusarium wilt, caused by Fusarium oxysporum f. sp. ciceris (FOC), is responsible for low productivity in chickpea. To date, eight pathogenic races of FOC (race 0, 1A, and 1B/C, 2-6) have been reported worldwide. The development of resistant cultivars using different conventional breeding methods is very time consuming and depends upon the environment. Modern technologies can improve conventional methods to solve these major constraints. Understanding the molecular response of chickpea to Fusarium wilt can help to provide effective management strategies. The identification of molecular markers closely linked to genes/QTLs has provided great potential for chickpea improvement programs. Moreover, omics approaches, including transcriptomics, metabolomics, and proteomics give scientists a vast viewpoint of functional genomics. In this review, we will discuss the integration of all available strategies and provide comprehensive knowledge about chickpea plant defense against Fusarium wilt.

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Soybean is considered one of the important crops among legumes. Due to high nutritional contents in seed (proteins, sugars, oil, fatty acids, and amino acids), soybean is used globally for food, feed, and fuel. The primary consumption of soybean is vegetable oil and feed for chickens and livestock. Apart from this, soybean benefits soil fertility by fixing atmospheric nitrogen through root nodular bacteria. While conventional breeding is practiced for soybean improvement, with the advent of new biotechnological methods scientists have also engineered soybean to improve different traits (herbicide, insect, and disease resistance) to fulfill consumer requirements and to meet the global food deficiency. Genetic engineering (GE) techniques such as transgenesis and gene silencing help to minimize the risks and increase the adaptability of soybean. Recently, new plant breeding technologies (NPBTs) emerged such as zinc-finger nucleases, transcription activator-like effector nucleases, and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR/Cas9), which paved the way for enhanced genetic modification of soybean. These NPBTs have the potential to improve soybean via gene functional characterization precision genome engineering for trait improvement. Importantly, these NPBTs address the ethical and public acceptance issues related to genetic modifications and transgenesis in soybean. In the present review, we summarized the improvement of soybean through GE and NPBTs. The valuable traits that have been improved through GE for different constraints have been discussed. Moreover, the traits that have been improved through NPBTs and potential targets for soybean improvements via NPBTs and solutions for ethical and public acceptance are also presented.

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S-adenosyl-l-methionine (SAM) is ubiquitous in living organisms and plays important roles in transmethylation, transsulfuration and transamination in organisms. Due to its important physiological functions, production of SAM has attracted increasing attentions. Currently, researches on SAM production mainly focus on microbial fermentation, which is more cost-effective than that of the chemical synthesis and the enzyme catalysis, thus easier to achieve commercial production. With the rapid growth in SAM demand, interests in improving SAM production by developing SAM hyper-producing microorganisms aroused. The main strategies for improving SAM productivity of microorganisms include conventional breeding and metabolic engineering. This review summarizes the recent research progress in improving microbial SAM productivity to facilitate further improving SAM productivity. The bottlenecks in SAM biosynthesis and the solutions were also addressed.

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Feeding 10 billion people sustainably by 2050 in the era of slow genetic progress has spurred urgent calls to bring more crops per unit time. Over the last century, crop physiologists and breeders have been trying to alter plant biology to investigate and intervene in developmental processes under controlled chambers. Accelerating the breeding cycle via "speed breeding" was the outcome of these experiments. Speed breeding accelerates the genetic gain via phenome and genome-assisted trait introgression, re-domestication, and plant variety registration. Furthermore, early varietal release through speed breeding offers incremental benefits over conventional methods. However, a lack of resources and species-specific protocols encumber the technological implementation, which can be alleviated by reallocating funds to establish speed breeding units. This review discusses the limitations of conventional breeding methods and various alternative strategies to accelerate the breeding process. It also discusses the intervention at various developmental stages to reduce the generation time and global impacts of speed breeding protocols developed so far. Low-cost, field-based speed breeding protocol developed by Punjab Agricultural University, Ludhiana, Punjab, India to harvest at least three generations of wheat in a year without demanding the expensive greenhouses or growth chambers is also discussed.

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Quinoa (Chenopodium quinoa) is a well-known climate-resilient crop and has been introduced into multiple marginal lands across the world, including China, to improve food security and/or balanced nutrient supplies. Conventional breeding has been widely applied in the selection and breeding of quinoa varieties in China since 1980s; however, few studies have been implemented on the genetic variances among different varieties developed by diversity breeding objectives. In this study, the phenotypic and genetic differences between two varieties (Longli-4 and CA3-1) from China were systematically analyzed. A total of 407,651 and 2,731,411 single nucleotide polymorphisms (SNPs) and 212,724 and 587,935 small insertion and deletion (INDELs) were detected for Longli-4 and CA3-1, respectively, when compared with the reference genome of PI614886. The SNPs/INDELs were unevenly distributed across each chromosome for both varieties. There were 143,996 SNPs and 83,410 INDELs shared between Longli-4 and CA3-1, accounting for 4% of the total variances. The variation was then screened based on the SNP effects. There were 818 and 73 genes with the variety-specific non-synonymous and stop-gain variation in Longli-4, whereas there were 13,701 and 733 genes in CA3-1. Specifically, 3501 genes with the non-synonymous variation and 74 genes with the stop-gain variation were found in both Longli-4 and CA3-1. These results suggest that convergent selection occurred during the different breeding processes. A set of candidate genes related to agronomic traits and domestication were further selected to detect the genetic divergence in detail in the two varieties. Only one domestication gene was identified having Longli-4-specific stop-gain variation. Twelve candidate genes related to betalain (1), flowering (4), seed size (2), domestication (1), and saponin (4) were identified having CA3-1-specific stop-gain variation. Interestingly, one seed size gene homologous of CKX1 (cytokinin oxidase/dehydrogenase 1) had the stop-gain variation in both varieties. This research will therefore provide guidance for the molecular-assisted breeding in quinoa.

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Rice production needs to be sustained in the coming decades, as the changeable climatic conditions are becoming more conducive to disease outbreaks. The majority of rice diseases cause enormous economic damage and yield instability. Among them, rice blast caused by Magnaportheoryzae is a serious fungal disease and is considered one of the major threats to world rice production. This pathogen can infect the above-ground tissues of rice plants at any growth stage and causes complete crop failure under favorable conditions. Therefore, management of blast disease is essentially required to sustain global food production. When looking at the drawback of chemical management strategy, the development of durable, resistant varieties is one of the most sustainable, economic, and environment-friendly approaches to counter the outbreaks of rice blasts. Interestingly, several blast-resistant rice cultivars have been developed with the help of breeding and biotechnological methods. In addition, 146 R genes have been identified, and 37 among them have been molecularly characterized to date. Further, more than 500 loci have been identified for blast resistance which enhances the resources for developing blast resistance through marker-assisted selection (MAS), marker-assisted backcross breeding (MABB), and genome editing tools. Apart from these, a better understanding of rice blast pathogens, the infection process of the pathogen, and the genetics of the immune response of the host plant are very important for the effective management of the blast disease. Further, high throughput phenotyping and disease screening protocols have played significant roles in easy comprehension of the mechanism of disease spread. The present review critically emphasizes the pathogenesis, pathogenomics, screening techniques, traditional and molecular breeding approaches, and transgenic and genome editing tools to develop a broad spectrum and durable resistance against blast disease in rice. The updated and comprehensive information presented in this review would be definitely helpful for the researchers, breeders, and students in the planning and execution of a resistance breeding program in rice against this pathogen.

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Nutrient enriched crops (NECs) were developed through biofortification as a tool to reach the world's most vulnerable. The delivery model developed by HarvestPlus for the scaling of NECs relies on commercial demand from food businesses and consumers, coupled with the ability to promote and market foods that comply with legislation. This review of standards, regulations, and laws across the value chain in 20 countries demonstrates that existing provisions for food labeling are sufficient to carry out sales and marketing of foods made from conventionally bred NECs. The term biofortification is not necessary to create demand and, potentially, is counterproductive. Promoting the natural source of vitamins and minerals and relevant nutrition claims is the most effective and simple way to signpost healthier products to consumers. Until 2021, it was not possible to distinguish NECs at the grain level from the market standard. The development of a globally relevant Publicly Available Specification allows traders to demand grains that offer a substantial increase in zinc, iron, or vitamin A. Addressing this gap at the grain level ensures that standards and regulations are available end-to-end in the food supply chain providing the enabling environment for the rapid scale of NECs.

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Lentil, an important cool season food legume, is a rich source of easily digestible protein, folic acid, bio-available iron, and zinc nutrients. Lentil grows mainly as a sole crop in the winter after harvesting rice in South Asia. However, the annual productivity is low due to its slow growth during the early phase, competitive weed infestation, and disease outbreaks during the crop growth period. Disease resistance breeding has been practiced for a long time to enhance resistance to various diseases. Often the sources of resistance are available in wild crop relatives. Thus, wide hybridization and the ovule rescue technique have helped to introgress the resistance trait into cultivated lentils. Besides hybridization, induced mutagenesis contributed immensely in creating variability for disease tolerance, and several disease-resistant mutant lines have been developed. However, to overcome the limitations of traditional breeding approaches, advancement in molecular marker technologies, and genomics has helped to develop disease-resistant and climate-resilient lentil varieties with more precision and efficiency. This review describes types of diseases, disease screening methods, the role of conventional and new breeding technologies in alleviating disease-incurred damage and progress toward making lentil varieties more resilient to disease outbreaks under the shadow of climate change.

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Pomegranate (Punica granatum) has staminate (male), androgynous (hermaphrodite), and intermediate flower types. Floral characterization is difficult for breeding efficiency across many pomegranate genotypes in Pakistan, which is essential for pomegranate cultivar enhancements. The present research focused on the floral characterization and breeding efficiency of fifteen pomegranate genotypes. Flower sex ratio, floral morphological parameters, i.e., flower length, ovary width, flower notch, flower tip and stigma with style length, and fruit set percentage were examined during the experiment. In terms of sex ratio, male flowers were found to be higher among all genotypes. Due to clear differences in flower length, width, and heterostyly facilitating visual identification of the hermaphrodite flowers, genotype Ternab-2, Kandhari White, and Kandhari Red had higher fruit set (≥70%) among all cross combinations attempted. Genotype Sava had higher flower length and heterostyly of hermaphrodite flower type, but ovary width was not very distinct, leading to average crossing success (85-34%). In conclusion, single or combination of morphological characters can be used for accurate identification of hermaphrodite flowers, which can improve hybrid efficiency and fruit set after artificial cross-pollination.

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At least 75% of the world's grain production comes from the three most important cereal crops: rice (Oryza sativa), wheat (Triticum aestivum), and maize (Zea mays). However, abiotic stressors such as heavy metal toxicity, salinity, low temperatures, and drought are all significant hazards to the growth and development of these grains. Quantitative trait locus (QTL) discovery and mapping have enhanced agricultural production and output by enabling plant breeders to better comprehend abiotic stress tolerance processes in cereals. Molecular markers and stable QTL are important for molecular breeding and candidate gene discovery, which may be utilized in transgenic or molecular introgression. Researchers can now study synteny between rice, maize, and wheat to gain a better understanding of the relationships between the QTL or genes that are important for a particular stress adaptation and phenotypic improvement in these cereals from analyzing reports on QTL and candidate genes. An overview of constitutive QTL, adaptive QTL, and significant stable multi-environment and multi-trait QTL is provided in this article as a solid framework for use and knowledge in genetic enhancement. Several QTL, such as DRO1 and Saltol, and other significant success cases are discussed in this review. We have highlighted techniques and advancements for abiotic stress tolerance breeding programs in cereals, the challenges encountered in introgressing beneficial QTL using traditional breeding techniques such as mutation breeding and marker-assisted selection (MAS), and the in roads made by new breeding methods such as genome-wide association studies (GWASs), the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system, and meta-QTL (MQTL) analysis. A combination of these conventional and modern breeding approaches can be used to apply the QTL and candidate gene information in genetic improvement of cereals against abiotic stresses.

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With an increasing interest and demand for biotechnology crops in agriculture worldwide, genetically modified (GM) breeding stacks produced by conventional breeding of previously approved GM single events remain popular for farmers in GM crop cultivation countries. However, regulations on stacks vary in each country. Currently, Korea requires approval for all breeding stacks intended for cultivation. To determine whether the stack is subject to a full safety assessment as a new GM crop, molecular characterization, protein expression, composition analysis, and agronomic characterization data are required. Korea's regulatory policy on stacks has not adopted the high-covers-low concept; therefore, subcombinations of already approved higher combination events are subject to breeding stack review if any subcombination was purposefully bred for cultivation use. This review will help promote the efficient management of GM breeding stacks in Korea in the future.

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Faba bean is a cool-season grain legume crop, which is grown worldwide for food and feed. Despite a decrease in area under faba bean in the past, the interest in growing faba bean is increasing globally due to its high seed protein content and its excellent ecological service. The crop is, however, exposed to diverse biotic and abiotic stresses causing unstable, low grain yield. Although, sources of resistance to main diseases, such as ascochyta blight (Ascochyta fabae Speg.), rust (Uromyces viciae-fabae (Pers.) Schroet.), chocolate spot (Botrytis fabae Sard.) and gall disease (Physioderma viciae), have been identified, their resistance is only partial and cannot prevent grain yield losses without agronomical practices. Tightly associated DNA markers for host plant resistance genes are needed to enhance the level of resistance. Less progress has been made for abiotic stresses. Different breeding methods are proposed, but until now line breeding, based on the pedigree method, is the dominant practice in breeding programs. Nonetheless, the low seed multiplication coefficient and the requirement for growing under insect-proof enclosures to avoid outcrossing hampers breeding, along with the lack of tools such as double haploid system and cytoplasmic male sterility. This reduces breeding population size and speed of breeding hence the chances of capturing rare combinations of favorable alleles. Availability and use of the DNA markers such as vicine-convicine (vc -) and herbicide tolerance in breeding programs have encouraged breeders and given confidence in marker assisted selection. Closely linked QTL for several biotic and abiotic stress tolerance are available and their verification and conversion in breeder friendly platform will enhance the selection process. Recently, genomic selection and speed breeding techniques together with genomics have come within reach to accelerate the genetic gains in faba bean. Advancements in genomic resources with other breeding tools, methods and platforms will enable to accelerate the breeding process for enhancing genetic gain in this species.

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Cereals and pulses are consumed as a staple food in low-income countries for the fulfillment of daily dietary requirements and as a source of micronutrients. However, they are failing to offer balanced nutrition due to deficiencies of some essential compounds, macronutrients, and micronutrients, i.e., cereals are deficient in iron, zinc, some essential amino acids, and quality proteins. Meanwhile, the pulses are rich in anti-nutrient compounds that restrict the bioavailability of micronutrients. As a result, the population is suffering from malnutrition and resultantly different diseases, i.e., anemia, beriberi, pellagra, night blindness, rickets, and scurvy are common in the society. These facts highlight the need for the biofortification of cereals and pulses for the provision of balanced diets to masses and reduction of malnutrition. Biofortification of crops may be achieved through conventional approaches or new breeding techniques (NBTs). Conventional approaches for biofortification cover mineral fertilization through foliar or soil application, microbe-mediated enhanced uptake of nutrients, and conventional crossing of plants to obtain the desired combination of genes for balanced nutrient uptake and bioavailability. Whereas, NBTs rely on gene silencing, gene editing, overexpression, and gene transfer from other species for the acquisition of balanced nutritional profiles in mutant plants. Thus, we have highlighted the significance of conventional and NBTs for the biofortification of cereals and pulses. Current and future perspectives and opportunities are also discussed. Further, the regulatory aspects of newly developed biofortified transgenic and/or non-transgenic crop varieties via NBTs are also presented.

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In Asia, cassava (Manihot esculenta) is cultivated by more than 8 million farmers, driving the rural economy of many countries. The International Center for Tropical Agriculture (CIAT), in partnership with national agricultural research institutes (NARIs), instigated breeding and agronomic research in Asia, 1983. The breeding program has successfully released high-yielding cultivars resulting in an average yield increase from 13.0 t ha-1 in 1996 to 21.3 t ha-1 in 2016, with significant economic benefits. Following the success in increasing yields, cassava breeding has turned its focus to higher-value traits, such as waxy cassava, to reach new market niches. More recently, building resistance to invasive pests and diseases has become a top priority due to the emergent threat of cassava mosaic disease (CMD). The agronomic research involves driving profitability with advanced technologies focusing on better agronomic management practices thereby maintaining sustainable production systems. Remote sensing technologies are being tested for trait discovery and large-scale field evaluation of cassava. In summary, cassava breeding in Asia is driven by a combination of food and market demand with technological innovations to increase the productivity. Further, exploration in the potential of data-driven agriculture is needed to empower researchers and producers for sustainable advancement.