Bringing the 4Rs to Life in Jharkhand State, India

A visit to the IPNI Global Maize experimental site in Ranchi, Jharkhand. Pictured (left) Rakesh Kumar, collaborating researcher, (center) the site’s farmer, and (right) Dr. A. Johnston, IPNI VP Asia, Africa & Mid East

From 2008 to 2013, the International Plant Nutrition Institute (IPNI) ran the Global Maize Project in the Jharkhand state of India. This interdisciplinary, international research effort had an overall objective of creating local, ecological intensification (EI) practices for maize production that increase yields at a faster pace than current farmer practices. Ecological intensification practices entail “using land, water, biodiversity and nutrients efficiently and in ways that are regenerative, minimizing negative impacts.” (FAO)

This study provides scientific insight into the impact of moving away from traditional practices and towards a more site-specific approach based on 4Rs: it is possible to achieve realistically attainable grain yield targets while also reducing any potential for negative impacts to the environment in and around the field by applying fertilizer using the right mix of nutrients (source) at the right rate and the right time.

In South Asia, one of the two study sites for this project is located in Ranchi, the capital of India’s Jharkhand state. In Ranchi, farmers typically rely less on fertilizer than on livestock manure. With the objective of improving the productivity of the region’s maize-wheat cropping system, the Global Maize Project set forth to compare the effects of farmer’s existing fertilizer application practices (FFP) to those of ecological intensification (EI).

The EI practices showcased by the Global Maize Project used a balanced application of N, P and K fertilizers (180-90-100 kg/ha) rather than the FFP of relying on a large manure application (5 t/ha) and a small amount of N fertilizer (40 kg N/ha). Researchers also tested 4R nutrient management strategies designed to further enhance the efficiency for N use in the system.

The results speak from themselves: the average maize grain yields under EI were 7.0 t/ha, while farm practice only produced 1.0 t/ha; N fertilizer use efficiency was improved from 25 kg grain/kg fertilizer N under farmer practice to 44 kg/kg under EI.

Read more about the Global Maize Project here.