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Abstract Striga hermonthica is fast spreading in the Nigerian savanna and is predicted to encroach into the rainforest part of the country soon. S. hermonthica seedbanks in savanna soils have continued to rise due to poor agronomic practices by smallholder farmers. Considering differences in soil, climate, and agronomic practices within the savanna endemic agroecology, the severity of the infestation of S. hermonthica has varied from one location to another. Hence, there is a need to model a site-specific management approach for S. hermonthica in Nigeria. This review aims to understand the state-of-the-art management of S. hermonthica in Nigeria’s upland rice fields and further harmonize potential management approaches. Based on studies conducted in Nigeria, reducing S. hermonthica parasitism over a long-term period in the Savanna ecology of Nigeria implies the rotation of upland rice with trap crops, and enhancement of nitrogen fertility in farmers’ fields, combined with the use of seed-treated resistant or tolerant cultivars. In practical terms, farmer’s-research engagement in the long term is pertinent to reduce the severity of S. hermonthica in threatened areas. [ABSTRACT FROM AUTHOR]

The demand for rice to meet the dietary need in low-income countries is expected to witness an exponential rise as the population increases. Meeting the rice demand domestically has remained challenging due to significant yield loss caused by several biotic and abiotic factors. Among these factors, one of the most important is the high weed pressure that ravages the upland rice ecology. In Nigeria, several independent weed control techniques, such as physical, chemical and cultural methods, have been recommended and adopted for weed control across varying rice upland ecologies. However, outcomes of these approaches when used independently have not consistently led to an increase in yield. There remains an outstanding deficit between the actual yield and the potential rice yield. This review aimed to identify potential research gaps, and quest effective and sustainable weed management strategies in smallholder upland rice farming systems in Nigeria. A critical analysis of studies suggests the potential of sustainable weed management practices if adopted and adapted smartly in different upland ecologies in Nigeria. Competitiveness of upland rice against weeds can be enhanced through strategic integration of weed competitive cultivars, optimum nitrogen application timings (within weed-free periods), uniform plant spacing, and high seeding rates, with conventional herbicide/manual weed control practices. However, such management practices can only be engaged where inputs are supplied on time and the technical know-how is extended to farmers. The review equally highlights potential research gaps for further studies. [ABSTRACT FROM AUTHOR]