The effect of the indigenous cultural practices of in-ground storage and piecemeal harvesting of sweetpotato on yield and quality losses caused by sweetpotato weevil in Uganda. uri icon

abstract

  • Traditionally, in Uganda most farmers growing sweetpotato practise in-ground storage combined with piecemeal harvesting. Several times during the growing period, between 3 and 7-12 months after planting, large roots are removed from individual plants and small roots are allowed to remain in the ground to enlarge further. The overall aim of the practice is to maintain a supply of roots in the ground for the longest possible period. In a series of four trials, once-over harvests at different intervals after planting and a simulated piecemeal harvesting treatment are compared for yield and quality losses caused by sweetpotato weevils (Cylas puncticollis and C. brunneus). For the once-over harvests, the percentage of damaged roots increased linearly the longer the harvest was delayed. Losses ranged between 3% at a harvest 3.5 months after planting (MAP) and 73% at 9.5 MAP. The total yield and undamaged yield for the piecemeal harvesting treatments were comparable to the yields at the optimum harvest times for once-over harvesting at 6-7.5 MAP. The results indicate that piecemeal harvesting is a practice with a controlling effect on sweetpotato weevil infestation. (C) 1997 Elsevier Science B.V.

publication date

  • 1997
  • 1997