University of Tennessee
National University of Lesotho, Growing Nations, Global Conservation Agriculture Program, International Maize and Wheat Improvement Center
Forbes Walker, Dayton Lambert,Michael Wilcox, Makoala Marake, August Basson, Patrick Wall
Subsistence farmers across Southern Africa struggle with food security and often address the shortfall by plowing more land. This approach usually results in fewer crops due to less timely weeding, limited inputs such as fertilizer being spread across a larger area, and higher erosion rates due to larger tracts of erodible, residue-free land. The continued use of this approach has resulted in degraded soils that further limit crop potential. To address these challenges, this project looks at the effectiveness of different no-till and tilled crop management systems in Lesotho and Mozambique. The goal is to find an appropriate cereal, grass, and legume cover-crop mix that protects the soil surface from erosion, builds soil organic matter, sequesters carbon, limits weed germination, enhances soil fertility, and increases yields and income through adaptation of conservation agriculture systems to local conditions.
1. Integrate cover crops into CAS to protect soil from erosion; provide weed suppression or control; include crop rotations that provide forages for livestock; improve soil quality as measured by soil C; decrease risk and vulnerability to drought. 2. Determine the agronomic and economic fertilizer rate for maize planted using different planting configurations in no-till conditions. 3. Characterize the composition and contribution of N and C from legume/grass cover crops and determine the best species for maintaining soil residue cover until after maize crop harvest. 4. Determine the short- and long-term impacts of CAS on gender equity especially in terms of household income and economic impact and to involve women in decisions that impact their welfare. 5. Evaluate ways and means to improve fertilizer adoption rates among smallholder farmers, the degree to which market structure influences fertilizer use, and determine welfare implications based on price margins.
LTRA-9 is generating sociologic, economic, agronomic, and fundamental nutrient cycling data that will be integrated into farming systems that can be further adapted on the farm. Current results indicate that maize yields--the staple crop in Lesotho and Mozambique--greater than ten times the current national average in Lesotho are attainable with limited chemical application if a winter cover crop is successfully established. These results are encouraging and suggest that food security can be improved if the knowledge gained during the KAP is incorporated into the CAS through the ATP.