## 1 Introduction  
The quest to apply nanotechnology in agriculture arises from the fact that human population is constantly on the rise, which necessitates the need for more food. Population survey has estimated about 9.6 billion people by the end of 2050 [1]. Farm lands are losing their fertility due to human activities on them and societal change in lifestyle. This invariably affects the production of crops and could lead to famine and hunger, thus concerted efforts are necessary to improve plants for enhanced production. Nanotechnology serves as the latest technology for precision agriculture,whereby strategies are formulated and channeled towards meeting with food demands of the increasing human population. There is a diversion from the traditional ways of crop production to technologies that could increase agricultural productivities with required nutrients, cost effective and efficient resource use that guarantees nutrient security, uplifts the value of production, boosts farmers' economy, delivers agri-value chain to rural partakers and supports pollution free environment [2]. This technology uses improved materials to add value to agriculture, by exploiting the nanoscale properties. Nanotechnology, as applied to agriculture, is bridging the gap in nutrient loss and fortification of crops. Farmers are using this science in the nano-regime to boost the quality and quantity of agricultural produce. The application of nanotechnology in agriculture includes nanobiotechnology, livestock, nanotoxicology, agrochemicals, hydroponics, biotechnology, etc. Urban agriculture that makes use of recent nanotechnologies has the potential to contribute immensely to food security and healthy nutrition. Although there are associated risks from chemicals which may have emanated from soils, water or air [3], the ultimate goals for application of nanomaterials in agriculture spans reducing hazard chemicals, nutrient losses, pest control and crop yield improvement [4]. The nutrients needed by the plants are fortified in the fertilizers, with the belief that they could be absorbed by the plants. The lack of the micronutrients is manifested by abnormal growth of the plant parts; however, sometimes the soil may not be deficient of the micronutrient, rather the roots are unable to absorb and translocate the nutrients due to small root pore size. It is, therefore, imperative to explore the strategies of improving crop quality and their essential nutrients to meet the food demands of the growing populace. The use of chemical fertilizers is an age long practice and has tremendously increased crop yields. However, they lead to soil mineral imbalance, destroy the soil structure, soil fertility and general ecosystem, which are serious impediments in the long term. To deal with the situation, it is pertinent to develop smart materials that can release nutrients to targeted areas and contribute to clean environment. Recent studies have shown that graphene is a promising material that could serve as a carrier for plant nutrients. It is capable of slow and controlled release of nutrient for the plants benefit, and ultimately increases the amount of crop production with low environmental impact [5]. Nanotechnology seems to be the alternative that could revolutionize this field of agriculture as the entire nanotechnology industry had grown to $1 trillion in 2015 [6]. Plants remain the primary source of nourishment for humans, and food quality determines the health of majority of the people. Staple foods are usually high calorific foods, consumed regularly in high quantity, which becomes dominant part of a standard diet in a community. As a result, there is high correlation between staple foods and nutrition of its consumers, especially among the rural and poor communities who rarely have other sources of nutrient supplementation. Lack of essential micronutrients in food is common in such areas. These have become a global issue with serious adverse effects [7; 8; 9; 10; 11].