Zinc and iron application in conjunction with nitrogen for agronomic biofortification of field crops – a review

Abstract

Context Maintaining food and nutritional security for the ever increasing population of the world is a great chllenge. Zinc and iron are important micronutrients for both human health and plant growth. Insufficient intake of these micronutrients leads to their deficiency in human body which causes morbidity and mortality in different age groups of poor populations in developing countries. Aims Therefore, agronomic biofortification is considered the most promising approach to alleviate zinc and iron malnutrition in developing countries. Methods The studies reviewed in this article clearly show that the combined application of zinc and nitrogen, iron and nitrogen, and zinc, iron and nitrogen to the soil or to the foliage during the reproductive phase leads to enhanced nutrient (zinc and iron) content in edible parts of crop plants. This happens as the remobilisation and translocation of zinc, iron and urea are governed by the same genetic pathways inside the plant. Key results The soil/foliar application of micronutrients (zinc and iron) along with nitrogen (mainly through urea) improves not only the micronutrient (zinc and iron) content in edible parts of the crop plants but also the crop productivity, and thus, is a win–win situation for growers as well as consumers. Conclusions Foliar application of urea at 1–2% along with zinc or iron or both during the reproductive phase has been found more effective for biofortification point of view. Implications This article reviews the effects of zinc and iron application in combination with nitrogen on agronomic biofortification in important field crops.

RETRACTED: Interaction between zinc and selenium bio-fortification and toxic metals (loid) accumulation in food crops

“…Researchers around the world are trying to compensate by enriching food products with zinc and selenium for their deficiency in the diet. Agronomic biofortification with Zn and Se have been widely investigated in recent years ( Manojlović et al., 2019 ; Izydorczyk et al., 2021 ; Yang et al., 2021 ; Jalal et al., 2022 ; Kaur and Singh, 2022 ; Silva et al., 2022 ). Improvement of crop varieties either by traditional breeding or transgenic has its own advantages, as, after the initial research and development, the benefits could be harnessed from these nutritionally enhanced crops with little more investments in the future.…”

Kernel color and fertilization as factors of enhanced maize quality

“…This indicated that apart from the genotype, other cropping practices could influence the share of phytic acid, affecting antioxidant activity. It is well known that urea is successfully used for biofortification to enhance Zn and Fe accumulation in crop grains ( Pal et al., 2021 ; Kaur and Singh, 2022 ). In this study, urea primarily decreased the ratio of phytic acid with Mg, Fe, Mn, and Zn even in red-kernel maize, thereby contributing to their better potential accessibility.…”

Agronomic innovations for enhancement of zinc content in pulses: A review

“…The data regarding foliar application of zinc on zinc content in grain of pulses are presented in Table 2, which clearly shows tremendous potential of zinc enhancement with foliar application of zinc. The combined use of zinc and urea (nitrogen) further improves zinc content in the grain over the sole use of zinc (Kaur and Singh 2022).…”