A review of zinc nutrition and plant breeding

Plants require the proper balance of zinc (Zn) for normal growth and optimum yield. Interest in Zn has risen in the last decade because Zn defciency stress is extensive in many areas, causing decreases in crop yields. Zn defciency also decreases the amount of Zn in cereal grain and diminishes its nutritional quality. Hence, increasing the Zn content of the edible portions of crops should be considered in plant breeding. Available data indicate that Zn enrichment traits are present within the genomes of crops that could allow for substantial increases in the Zn concentration of edible parts without negatively impacting yield. Increasing the amount of Zn in food crops can improve the Zn status of people. Furthermore, the use of Zn-dense seeds results in greater seedling vigor and increased crop yields when the seeds are sown in Zn-poor soils. Progress toward developing mineral-dense seed has mainly relied upon conventional plant breeding approaches, a process that is labor-intensive and time-consuming. Hence, the identifcation of DNA markers that are diagnostic of Zn effciency can accelerate the development of cultivars that can remain productive even in Zn-defcient soils. Additionally, these markers may be used to begin identifying the specifc genes responsible for differences in the response of genotypes to Zn defciency.