Enhancing Crop Productivity in Salt-Affected Environments by Stimulating Soil Biological Processes and Remediation Using Nanotechnology

Abstract

World food production systems primarily crop lands are set to face unprecedented stress for matching production with overwhelming population growth in the backdrop of increasing natural calamities and climate change. Another green revolution does not seem likely with the same approaches as followed in the past. A large extent of marginally productive lands (including salt affected) in India and the world presents opportunity for bolstering food security via land reclamation, improved productivity, and resource conservation by enhancing biological functions of soil. The presence of soluble salts in the soil and water, including surface water and groundwater, poses great threat to productivity of land. Land use practices, such as clearing and irrigation, have significantly increased the extent of the problem. The most obvious effect of salts in soil includes decline in agricultural productivity. High concentrations of salt in the soil are toxic to plants, restrict plant uptake of water, and prevent plants from taking up essential nutrients. There are several approaches to manage these lands including chemical reclamation, but they are very resource expensive. Nanotechnology as an emerging science may play a greater role for managing these salt-affected marginal lands. Though nanotechnology, in respect of both research and development, is as yet at a nascent stage, it can be effectively directed toward understanding and creating improved materials, devices, and systems and in exploiting the nano-properties for managing these lands. Nanotechnology has not left agricultural sector untouched and promises to revolutionize the agricultural sector with new tools for molecular treatment of plant diseases, rapid detection of diseases, and enhancing the ability of plant to absorb nutrients, thus increasing soil fertility and crop production. The potential of nanotechnology is yet to be fully exploited in salt-affected land management, and agriculture, yet if once realized, it is likely to bring a sea change in agricultural production and productivity.

Rhizosphere is a site where complex interactions occur between the root and associated microorganisms and high microbial diversity. The effects of engineered nanomaterials on populations of organisms and on entire ecosystems are essentially unexplored at this time even though naturally occurring nanoscale minerals are present in all ecosystems, and they play a significant role in soil productivity. Naturally occurring nanoparticles (NPs) contribute immensely to the biogeochemical cycling of carbon, nitrogen, sulfur, and phosphorus in the environment. While these naturally occurring NPs are ubiquitous, the extent to which engineered NPs will exhibit unique physical and chemical attributes in the soil is virtually unknown. Moreover, studies on the interactions between plant, soil, microorganisms, and the different NPs are shedding light on their interrelationships, thus providing new possible ways to exploit them for agricultural purposes. Although new finding initiatives for microbial research represent a unique opportunity for microbiologists to study these emerging technologies, it also presents significant challenges to a field of research that has little history of predicting the impact on different soil microbiological processes.