Prospects and challenges of emerging yam formal seed systems in West Africa

Aighewi, B., Aihebhoria, D., Balogun, M. & Mignouna, D. (2023). Prospects and challenges of emerging yam formal seed systems in West Africa. Morocco: Mohammed vi Polytechnic University, (1 p.).

Yam (Dioscorea spp.) is a staple tuber crop produced in parts of tropical Af rica, the Caribbean, Oceania, and South Asia. Typically, the crop is grown in traditional systems where there are no dedicated seed producers and farmers use seed f rom informal sources. Recently, technologies developed at the International Institute of Tropical Agriculture, Nigeria, were deployed to initiate formal yam seed systems in Nigeria and Ghana to enhance the availability of quality seed to millions of yam farmers in West Af rica. A study was conducted using a structured questionnaire to investigate how seed companies that engage in foundation and certified seed yam production were using the new technologies, and to assess the prospects for increasing the availability of quality seed through the formal seed system, as well as the challenges encountered. Results showed that seed companies were satisf ied using new technologies such as <10 g minitubers of improved varieties, compared to the 250 g seeds of landraces in informal production systems. They also use leaf-bud cuttings in hydroponic systems in screenhouses with up to 92% plant establishment, and 65% of the companies use locally available rice husk as a growth substrate. The improved practices used in screenhouses and f ields that are inspected and certified by the relevant quality control and certification agencies have great potential in enhancing the availability of quality seed yam. However, the aeroponic system was considered complicated and expensive, and not adopted despite the 95 to 97% plant survival in the system. Major challenges of the new system include limited knowledge on the storage requirement for 1 - 10 g foundation seeds and high storage losses (up to 38%) resulting from nematode infestation when seed was produced in the field. There is also an unwillingness by farmers to accept new varieties. In conclusion, the adoption of new technologies in the formal seed system with additional knowledge on storage and pest control will mitigate major bottlenecks in quality seed yam production and availability.