Tailoring crops with superior product quality through genome editing: an update.

MAIN CONCLUSION: In this review, using genome editing, the quality trait alterations in important crops have been discussed, along with the challenges encountered to maintain the crop products' quality. The delivery of economic produce with superior quality is as important as high yield since it dictates consumer's acceptance and end use. Improving product quality of various agricultural and horticultural crops is one of the important targets of plant breeders across the globe. Significant achievements have been made in various crops using conventional plant breeding approaches, albeit, at a slower rate. To keep pace with ever-changing consumer tastes and preferences and industry demands, such efforts must be supplemented with biotechnological tools. Fortunately, many of the quality attributes are resultant of well-understood biochemical pathways with characterized genes encoding enzymes at each step. Targeted mutagenesis and transgene transfer have been instrumental in bringing out desired qualitative changes in crops but have suffered from various pitfalls. Genome editing, a technique for methodical and site-specific modification of genes, has revolutionized trait manipulation. With the evolution of versatile and cost effective CRISPR/Cas9 system, genome editing has gained significant traction and is being applied in several crops. The availability of whole genome sequences with the advent of next generation sequencing (NGS) technologies further enhanced the precision of these techniques. CRISPR/Cas9 system has also been utilized for desirable modifications in quality attributes of various crops such as rice, wheat, maize, barley, potato, tomato, etc. The present review summarizes salient findings and achievements of application of genome editing for improving product quality in various crops coupled with pointers for future research endeavors.

Combining ability and heterosis studies for grain iron and zinc concentrations in pearl millet [Cenchrus americanus (L). Morrone].

Iron (Fe) and zinc (Zn) deficiency has been identified as a major food-related health issue, affecting two billion people globally. Efforts to enhance the Fe and Zn content in food grains through plant breeding are an economic and sustainable solution to combat micronutrient deficiency in resource-poor populace of Asia and Africa. Pearl millet, Cenchrus americanus (L). Morrone, considered as a hardy nutri-cereal, is the major food crop for millions of people of these nations. As an effort to enhance its grain mineral content, an investigation was conducted using line × tester analysis to generate information on the extent of heterosis, gene action, combining ability for grain yield potential, and grain mineral nutrients (Fe and Zn). The partitioning of variance attributable to parents indicated that the lines and testers differed significantly for the traits studied. For most of the attributes, hybrids that were superior to the parents in the desired direction in terms of per se performance were identified. The analysis of combining ability variance indicated the preponderance of both additive and non-additive genetic effects. Thus, reciprocal recurrent selection can be used to develop a population with high-grain Fe and Zn contents. The Fe and Zn content in grain exhibited a highly significant and positive association between them, whereas the Fe and Zn contents individually showed a negative, albeit weak, correlation with grain yield and a moderate positive relation with grain weight. This indicates that mineral nutrient contents in grains can be improved without significant compromise on yield. The consistency of these trends across the environment suggests that these findings could be directly used as guiding principles for the genetic enhancement of Fe and Zn grain content in pearl millet.