POTATO INTERCROPPING SYSTEMS WITH MAIZE AND FABA BEAN
Potato is a major cash crop for Bhutanese highland farmers, who widely\nuse intercropping systems combining potato (Solanum tuberosum) with\nmaize (Zea mays). Scarcity of information on existing cropping practices\nlimits the scope of present extension programs. Experiments evaluating\npotato intercropping systems with maize and faba bean (Vicia faba) were\nconducted at Yusipang (2700 m) and Kangma (1900 m). Potato yield\nreductions through intercropping ranged from 0-21 percent depending on\nyear, and location. Variation in planting geometry and maize planting\ndate did not affect potato yield reductions. The land equivalent ratio\nranged from 1.03-1.06 for faba bean and from 1.11 to 1.49 for maize\nintercropping systems. Compared to potato as a sole crop maize\nintercropping increased gross benefits in Kangma by 12-15 percent with\nmaize plant densities of 2.8 per m2. In Yusipang, gross benefits were\nnot increased through intercropping. Reducing risks of environmental and\nmarket impacts favor the use of intercropping systems.