Striga hermonthica
© Jos Raaijmakers, NIOO-KNAW


From Promise to Promise II 

The overall goal of PROMISE (PROmoting Microbes for Integrated Striga Eradication) is to develop innovative, sustainable, affordable and locally sourced  management strategies to control Striga and enhance crop yields for small-scale farmers in Sub-Saharan Africa. 

Stages of Promise I and II
Victoria Miles, NIOO-KNAW

Promise I

In the discovery project PROMISE I (2016-2022), we investigated the functional potential of soil and plant-associated microorganisms to disrupt the Striga life cycle. We accomplished this by identifying and characterizing a large collection of bacteria and fungi isolated from agricultural fields across the sorghum belt in Ethiopia. More specifically, we studied a diversity of mechanisms and the underlying chemistry by which soil and root-associated microorganisms can diminish the Striga seed bank or interfere with the early stages of root infection. The experimental work ranged from studying the effects of edaphic factors on microbial community diversity and functioning across different Ethiopian agro-ecologies and sorghum cultivars to microbe-mediated changes of host root architecture, root exudation, and induction of Striga resistance. We discovered the functional potential of soil and root-associated bacteria and fungi to: i) disrupt the early stages of the Striga life cycle through the production of Strigacidal volatile compounds, ii) cause Striga seed decay or suicidal germination, iii) degrade host-derived germination signals and haustorium-inducing factors, and iv) induce structural barriers (aerenchyma, suberin) in the host plant roots. In collaboration with local research institutes, we then developed initial strategies to augment Striga-suppressive activities of indigenous soil microbial communities to achieve Striga suppression in greenhouse and field settings.

Image: Jos Raaijmakers, NIOO-KNAW

Tested vs untested

Promise II

Building upon the finding of Promise I , Promise II aims to develop two innovative technologies that can increase crop yields for smallholder farmers  by diminishing the Striga seedbank and reducing root infections. We will focus on identifying affordable, locally sourced substrates rich in strigacidal volatiles. Additionally, we’ll examine the beneficial bacterial and fungal strains identified in Promise I to transform them into prototype microbial products to cause Striga seed decay and to protect root infections in sorghum, rice, and millet. 

Image: Jonne Rodenburg, University of Greenwich 

Striga asiatica on Maize

Global Accessibility Strategy

As part of the project, we will ensure effective communication, dissemination and monitoring of the outcomes of the project via a global access strategy developed for PROMISE II. By being in close contact with the farmers, we will ensure that the integration of the developed technologies is effective, safe and affordable for local business across the Sub-Saharan region.

Image: Jonne Rodenburg, University of Greenwich