This book covers the role and effects of nanofertilizers in agriculture and together with its companion book “Nanofertilizers for Sustainable Agriculture: Assessing Impacts on Health, Environment, and Economy� serves as an indispensable resource for researchers, agronomists, and policymakers exploring sustainable agriculture with nanotechnology. The book outlines the synthesis and formulation of nanoparticles tailored for agricultural applications and discusses the impact of nanofertilizers on crop well-being and soil fertility, including the pivotal role of plant growth-promoting microorganisms in nanoparticle-mediated agriculture. Divided into four sections, the book begins with an introduction to the relevance and specificities of nanotechnology in agriculture, including nonfertilizer synthesis and formulation, followed by a section dedicated to rhizosphere microorganisms and the impact of nanofertilizers in agricultural systems. Readers will learn about the impact of nanofertilizers on crop well-being and soil fertility, including the pivotal role of plant growth-promoting microorganisms in nanoparticle-mediated agriculture. The subsequent section of the book is devoted to the mechanisms of action of nanofertilizers, namely the ones governing the release, absorption, and translocation of nanonutrients in soil, and discusses the potential of biocatalysis in nanofertilizer development. The final section of the book discusses crop productivity and biofortification while unravelling the nuanced effects of nanoparticle doses, shapes, sizes, and compositions on crop yields and physiological activities. In this section, readers will also find diverse applications of nanofertilizers in stress tolerance, salinity, and environmental stress mitigation.