Publication Type

Journal Article

Journal Name

Journal of Agriculture and Food Research

Publication Date

12-1-2024

Abstract

The production gap between current and attainable yields is highest on Africa's smallholder farms, and some studies indicate that they might not benefit from the yield gains offered by conventional farming. Simultaneously, alternative farming systems like organic provide biodiversity and soil fertility advantages, but their ability to produce sufficient food is still under debate. Additionally, comparative data on the productivity of organic versus conventional in tropical regions are scarce or short-term. We investigated the crop productivity of organic and conventional farming systems using 15 years in two long-term systems comparison trials in Kenya. The trials were established in 2007 at two sites in the Central Highlands of Kenya. At each site, conventional and organic systems were compared at high input levels. The trial involved a three-year crop rotation cycle of maize, vegetables, legumes, and potatoes, repeated five times since its establishment. Management practices were kept similar in the first four rotations and revised in the fifth to improve systems representing best practices. Our results showed that while maize and baby corn had relatively low yield gaps (−13 to +12 %) between organic and conventional systems, cabbage, French beans, and potato had high yield gaps (−50 to −30 %). We attributed this to nutrient limitations and higher pest and disease damage. The yield gap could partially be closed by adopting best practices in the organic system, including system diversification and effective soil fertility, nutrient, and integrated pest management.

Keywords

Best-practice, Farming systems, Long-term experiment, Organic agriculture, Tropics

Funding Statement

The authors wish to acknowledge the financial support from the Biovision Foundation for Ecological Development, Coop Sustainability Fund, the Liechtenstein Development Service (LED), and the Swiss Agency for Development and Cooperation (SDC). They also wish to thank the management of the Kenya Agricultural and Livestock Research Organization (KALRO) for offering the trial site at Kandara and the management of Kiereni Primary School for offering the second trial site at Chuka. We are grateful to Ms. Jane Makena and Mr. James Karanja for managing the trial sites and the collection of data. The inputs and useful scientific discussions of the members of the Scientific Advisory Board Committees are gratefully acknowledged. Finally, we extend our gratitude to the paper's external reviewers for their valuable comments that helped further improve the manuscript.

Download

Share

COinS