Search

Food security is a serious issue in this era of rapidly growing population. Food security is threatened due to low crop yields around the world due to different biotic and abiotic stresses. The arable lands are decreasing due to different soil degradation process and thus prospect for increasing crop yields through extending areas under cultivation are not very bright. Hence, to achieve the food security on a sustainable basis, it is necessary to utilize degraded soils productively. Among the degraded soils, Salt-affected soils share the major fraction and their presence is prevalent in all continents. The adoption of different management techniques for productive use of salt-affected soils is thus pre-requisite for enhancing crop yields on such soils. These management strategies include management of irrigation water, reclamation techniques, raising beds, organic matter and salt tolerant crops like kallar grass. In addition to these, better fed plants have good potential to withstand with salinity and other stresses. Exogenous application of nutrients can alleviate the detrimental effects of salts. Silicon (Si) as a beneficial nutrient is known to improve plant growth particularly under abiotic stresses. It is helpful for plants in many ways as it improves plant water status in the context of relative water content and transpiration rate. The role of Si to promote the plant growth under salt-affected soils is reviewed in detail in this chapter.

Iron (Fe) deficiency is a prevalent nutritional deficiency throughout the world, affecting an estimated 3.7 billion people. Increasing Fe concentration in foodcrops is an important global challenge due to the high incidence of Fe deficiency in human population. Further, cereals grown on calcareous soil are low in Fe contents. High pH, high temperature, low organic matter and poorly managed soil with respect to fertility are the factors which cause low Fe availability to cereal crops in calcareous soil. Iron fertilization in calcareous soil is not effective due to their rapid conversion into unavailable forms and poor mobility of Fe in phloem. Iron-organic compounds in manure are effective in maintaining Fe availability to plants. Fe bioavailability inhibitors such as polyphenols and phytate inhibit iron absorption but it was concluded that their inhibitory effect on iron absorption can be limited by increasing iron content. Ferritin, an iron storage protein, can deposit thousands of iron atoms asnon-toxic form and ferritin iron is bioavailable to humans as ferrous sulphate. Improving both concentration and bioavailability of Fe in cereal grains is, therefore, an important challenge and a high-priority research area. Hence, there is a need for effective strategies to overcome Fe deficiency in cereals and to increase Fe bioavailabilty in cereals grains. Biofortification of food crops with Fe to combat iron deficiency problems in humans, is a cost-effective and sustainable agricultural strategy to alleviate malnutrition. We hypothesized that Fe nutrition management in calcareous soil can increase growth, yield and Fe bioavailability from cereals.