After an illustrious career at the Indian Council of Agricultural Research (ICAR)-Indian Agricultural Research Institute (IARI), New Delhi, for nearly two decades, Prasanna joined as Director of Global Maize Program in 2010 and served in that responsibility for nearly 15 years based in Nairobi, Kenya. As the Global Maize Program Director, Prasanna provided technical oversight for a wide range of multi-institutional projects focused on the development and deployment of elite, stress-resilient, and nutritionally enriched maize varieties across the tropics of sub-Saharan Africa, Asia, and Latin America. He has also spearheaded the application of innovative tools and technologies aimed at enhancing genetic gains and improving breeding efficiency, and established state-of-the-art research facilities in Africa and Asia, including the Maize Doubled Haploid facilities in Kiboko, Kenya, and Kunigal, India, and the Maize Lethal Necrosis (MLN) Screening Facility at Naivasha, Kenya. Under his leadership, adoption of CGIAR-related climate-resilient maize varieties in sub-Saharan Africa increased from 0.5 million hectares in 2010 to over 8.5 million hectares in 2024.

Prasanna led the CGIAR Research Program on Maize Agri-food Systems (MAIZE) from 2015 till 2021, an alliance of over 300 research and development institutions globally. He has been at the forefront in tackling the challenges of MLN disease in eastern Africa (since 2011), and the Fall Armyworm in Africa and Asia (since 2016 and 2018, respectively).

Together with an array of partners globally, Prasanna and the wider CGIAR team formulated the OneCGIAR Plant Health Initiative in 2021. Prasanna served as the Leader of the Plant Health Initiative, involving 10 CGIAR centers and over 120 national and international partners.

Prasanna has been conferred the title of CIMMYT Distinguished Scientist in 2024. He joined as CIMMYT Regional Director for Asia in January 2025, and as Managing Director of Borlaug Institute for South Asia (BISA) on 1st June 2025.

Prasanna has published over 250 research articles in various international journals of repute, and has a Scopus h-index of 60, and a Google Scholar h-index of 75. He has received several awards for his outstanding contributions to maize genetics and breeding, seed systems, post-graduate teaching, and popularization of science, including the Fellowship of National Academy of Agricultural Sciences (NAAS) in India, Shanghai Magnolia Award of China, and Dr M.S. Swaminathan Award for Leadership in Agriculture, conferred by the Trust for Advancement of Agricultural Sciences (TAAS) in India.