Sweetpotato commercial seed production – screenhouse practices


Experiences from the USA National Clean Plant Network for Sweetpotato (in North Carolina and Louisiana) and sub-Saharan Africa

This webinar is part of a series hosted by the CGIAR Research Program on Roots, Tubers, and Bananas (RTB) on quality seed. This cluster seeks to improve access to quality seed and improved varieties as well as develop methods and techniques to diagnose, evaluate and improve seed systems for banana, cassava, potato, sweetpotato, and yam.

The five crops are vegetatively propagated – through roots, stems, vines, and suckers – and share similar challenges, including a low multiplication rate during the early stages of planting material production. The RTB program promotes knowledge sharing among scientists and practitioners, which has enabled the adaptation of techniques across crops, from yam to potato, for example. This webinar will focus on aeroponics and semi-autotropic hydroponics (SAH).

DATES (two parts)

May 21, 2020
9:00 (US eastern standard)
May 28, 2020
9:00 (US eastern standard)


Rosemary Kihiu



A key stage in sweetpotato seed production is the transfer of pathogen-tested tissue culture (TC) plantlets to in vivo for production in screenhouses. Screenhouse propagation of vine cuttings is the opportunity to bulk up quality seed for commercial sales. This requires optimization of the ratio between TC plantlets and screenhouse plants and having the appropriate implementing management practices to reduce unit cost of production.

This webinar is an initial discussion to exchange experiences among colleagues involved in the USA National Clean Plant Network for Sweetpotato and researchers and practitioners in sub-Saharan Africa (SSA) who are involved in early generation seed production.

The event and discussion are open to the public and participation is expected from members of the sweetpotato speedbreed and seed communities of practice in SSA (e.g., NARIs, ARIs, development practitioners); and members of the RTB program for quality seed and improved varieties from the USA, Europe, Latin American, and Southeast Asia.

We see this webinar as an initial step to generate more in-depth exchange of information on screenhouse practices in the following areas:

  1. Media, containers, and nutrient mix used for screenhouse operations (including sandponics and semi-autotrophic hydroponics)
  2. Ratooning practice
  3. Irrigation practice
  4. Quality assurance practices (internal, external)
  5. Temperature and humidity management
  6. Other measures to reduce unit cost of production:
    • Lighting systems
    • Aeroponics
    • Staking/trellising
  7. Output measures (e.g., multiplication rate per plant per unit time; unit cost of production, volume/revenue per season or cycle)
  8. Varietal turnover including number of varieties per season