Status and prospects for improving yam seed systems using temporary immersion bioreactors

Abstract

Yam production is constrained by scarcity of clean seed, pests, diseases and low soil fertility in the informal seed system, which is still operational, causing up to 90% yield losses. Although meristem culture can be effective for producing healthy seed yam, its use is limited by slow rate of regeneration and propagation in conventional tissue cultures. In most crops tested, temporary immersion bioreactor systems (TIBs) increased propagation rates. To determine the potential of TIBs in improving the yam seed system, 23 databases were consulted and three returned a total of eight publications with only 2 for Dioscorea rotundata-cayenensis. Both plantlets and microtubers can be produced in TIBs, which will facilitate production of quality breeder, foundation and certified seeds and fast-track genetic improvement and the evolution of a formal from informal seed production system. Control of contamination, direct use of field explants, culture of micro-explants like immature embryos and anthers, increasing the size of microtubers produced and standardization for various economically important yam genotypes are knowledge gaps that require immediate research attention. No report has put a cost on yam TIBs, but it will be necessary to use cost-effective TIBs to encourage integration public-private partnerships into emerging formal seed system.

Genetic purity of yam (Dioscorea spp.) multiplied through different seed multiplication techniques based on DArT SNP markers

“…This will help reduce the lengthy time spent on varietal development. The success of the aeroponics and the TIBS in achieving the targets for which they were developed has been observed at IITA (Balogun et al, 2014;Maroya et al, 2014a). The tissue culture system even though not farmer-friendly, due to the dependency on a controlled laboratory environment unsusceptible to changing weather conditions, has been very helpful in generating clean, high-quality and uniform plants from otherwise unclean mother plants (Yam and Arditt, 2009).…”

“…This is due to one or a combination of the following factors: the complexity of the technique, the high cost associated with the technique and high dependency on technical know-how. The aeroponic system and the TIBS have been developed with the primary target of priming and sustaining the formal seed yam system for pre-basic and basic seed production (Balogun et al, 2014;Maroya et al, 2014a;Aighewi et al, 2015). These systems, however, could also be very useful in yam breeding programmes for developing large quantities of high-quality seed yam for multi-location trials.…”

Collection, Characterizaton and Conservation of Genetic Resources of Yam Cultivars From Ekiti State, Nigeria

“…Yam research in Nigeria has focused on propagation, the state of the seed yam system, conservation of yam germplasm and improvement through selection and breeding. The work on yam propagation has addressed mini setts (Balogun 2004(Balogun , 2007(Balogun , 2009, micropropagation through plantlets raised in regular cultures and aeroponics, microtuber production (Balogun 2014;Aighewi et al 2015), generation of plantlets through regular callus production and somatic embryogenesis, production of encapsulated embryos and propagation from regular botanic seeds. Yam production in Nigeria is restricted to the South-Eastern, South-Western, Middle-Belt and East of River Niger zones where the soil fertility, humidity and rainfall permit its production.…”

Producción de ñame clon Criollo a partir de bulbillos aéreos

“…Además, los tubérculos, que constituyen la parte útil de la planta para la alimentación, se utilizan como material vegetal de plantación (Cabrera et al, 2010), y pueden abarcar una parte importante de la cosecha (35%) (Borges, 2011). La producción de ñame ha estado limitada por la escasez de semilla sana, baja fertilidad del suelo y la incidencia de plagas y patógenos en los sistemas tradicionales de cultivo (Balogun et al, 2014).…”