Comparative analysis for producing sweetpotato pre-basic seed using sandponics and conventional systems

Abstract

In Sub-Saharan Africa, sweetpotato pre-basic seed is multiplied in screenhouses using a sterilized soil substrate. This is expensive and unsustainable. The use of sand substrate with a fertigation system ("sandponics"), is an alternative. The study compared the cost-effectiveness for pre-basic seed production using the sandponics system to the conventional soil substrate for four genotypes. A randomized complete block split plot design was used, and data collected on vine traits over six harvests. Real-time cost data were collected for costeffectiveness analysis. Results showed a highly significant (p < .0001) 21.8% increase in the vine multiplication rate under the sandponics system. The cost of producing one sweetpotato node in sandponics was significantly lower by 0.009 US$. The cost-effectiveness of producing pre-basic seed in sandponics varied among the genotypes. The future use of sandponics is discussed with respect to the availability of soluble inorganic fertilizers, varietal specific response to nutrients, and labor implications.

Yield potential of sandponically produced sweetpotato (Ipomoea batatas (L.) Lam) pre-basic seed for selected genotypes

“…The superior field performance of planting materials sourced from the sandponics system compared to the conventional soil substrate planting materials considering vine survival, total storage root yield, number of storage roots per plant, and vine yield could be attributed to the higher residual nutrients in planting materials multiplied by the sandponics system as reported by Makokha et al (2020). This indicates that field establishment and growth of plants benefit from the residual effects of the system used for the multiplication of planting materials.…”

“…There have been efforts to build up seed systems steered from research and breeders focusing on varietal trials and release of new improved genotypes to consumers. However, multiplication of adequate quantities of pre-basic seed (also referred to as early generation seed) within a short period of time has been a limitation attributed to slow vine multiplication rate (VMR) and high costs using the conventional soil substrate method (Makokha et al 2020).…”

“…The conventional soil substrate media is composed of forest top soil, cow manure, and gravel in the ratio of 5:2:1, which is sterilized in a steam boiler for 30 min at 82°C using diesel as the source of energy. However, Makokha et al (2020) have shown that multiplication of pre-basic seed using this method is costly, is unsustainable, and does not achieve optimal yields.…”

Manual for sweetpotato pre‐basic seed production using the sandponics system

“…Research undertaken under phase II of the Sweetpotato Action for Security and Health in Africa (SASHA) project has demonstrated that sweetpotato pre-basic seed can be multiplied more cost-effectively in a sandponics system than when using the conventional soil substrate method (Makokha et al, 2019a). The VMR in the sandponics system is 22% higher when compared with the conventional soil substrate method.…”

Degeneration of sweetpotato seed in Tanzania: can cleaned-up, virus-tested seed help?

“…Mataya produced a similar number of vines in net tunnels and open fields for both ratooned and replanted crops. Genotypic variation influences sweetpotato vine production and this has also been reported in plants produced in screen houses using a sandponics system (Makokha et al, 2020). The morphology of cv.…”