Nanotechnology, Plant Nutrition and Climate Change
Nanotechnology is emerging out as the sixth revolutionary technology in the current era after the Industrial Revolution of mid 1700s, Nuclear Energy Revolution of the 1940s, The Green Revolution of 1960s, Information Technology Revolution of 1980s and Biotechnology Revolution of the 1990s. It is a new frontier with challenges and opportunities that will extend our reach and enrich our lives. The word Nanotechnology has originated from a Greek word which means “dwarf” and nanometer is 1 billionth of a meter (1 nm = 10-9 meter). Nanotechnology is defined as the understanding and control of matter at dimensions of roughly 1-100 nm, where unique physical properties make novel applications possible (EPA, 2007). Utilizing basic principles of nano-science and nano-technology, we can contribute significantly towards development of new agro-production and protection technologies. It is worthy to consider the following relationship between particle size and surface area what we have known for a long-time about how the properties of particles change as they decrease in size to the micron to submicron size range. For spherical particles, the ratio of surface area ‘A’ (A=4πr2) to volume ‘V’ (V= 4/3πr3) is inversely proportional to the particle radius ‘r,’ i. e. A/V = 3/r. This relationship tells us that as a particle becomes smaller, its surface area becomes an increasingly larger component of its overall form. Thus, reduction of particle sizes of the naturally occurring minerals is an important means to increase their reactivity in soil vis-à-vis availability to the growing plants. Vast deposits of minerals, which are not suitable for industrial use, can be made useful as sources of plant nutrients for the crop production. Our investigation clearly indicated that low grade rock phosphates, can easily be made as a source of P to the plant when they are converted to nano-size (<100 nm). Similarly, vast deposits of gluconite/waste mica, dolomite and magnetite (as source of Ca & Mg), pyrite (as source of Fe and S), can be made useful for agriculture use with a reduced cost and without impairing damage to environment. A protocol was developed to fortify the Urea granules with a consortium of nano-particles of Zn, Cu, Fe, and Si using oleoresin. This protocol can successfully be used to deliver nano-particles of micronutrients along with urea. The nano-particles coated urea, thus produced, contained 43.84% N, 2.20 mg Zn/g Urea, 1.10 mg Fe/g Urea, 0.66 mg Cu/g Urea and 1.06 mg Si/g Urea. Application of such urea @ 200 Kg/ha will supply, 440 g Zn, 220 g Fe, 132 g Cu and 212 g Si along
with 87.68 kg N/ha to the crops. A protocol has also been developed to coat the seeds of maize, soybean, pigeon pea and ladies finger with nano scale (<100 nm) ZnO powder. The most important advantage of seed coating with nano ZnO is that it does not exert any osmotic potential at the time of germination of the seed, thus, the total requirement of Zn of the crop can be loaded with the seed. This protocol of seed coating with ZnO can be used by the seed producing agencies to produce customized seed for Zn deficient areas of the country.