About the authors - Agriculture Cultivation Fruit Cultivation Sowing the seeds for better yams CGIAR SP IPM

About the authors

Coyne, D. Claudius-Cole, A.

Disadvantages: There is the need for specialized equipment and a fuel/energy source; the process is time-

consuming and slow; it may reduce germination of treated material, particularly certain sensitive cultivars (Coyne

et al., 2010).

Chemical seed sett treatment

Cut seed setts immersed in chemical

dip. – D. Coyne

The use of a recommended fungicide-insecticide

combination before planting has provided excellent

results for producing healthy seeds. This is ideally

applied by dipping setts into a liquid suspension, then

leaving them to dry before planting. Studies in West

Africa showed that a combination of a compatible

fungicide and insecticide was most effective in

increasing the yield, quality, and storability of seeds

(Kenyon, 2005). It is important to receive local

information from agro-input suppliers on safe and

suitable products for this use. Chemical dusts can also

be used, but may result in an uneven distribution.

Disadvantages: Care is required to prevent unwanted human and environmental contamination and to ensure

the safe disposal of excess chemicals and packages; this method is not suitable for organic crop production.

The dual combination of hot water treatment followed by chemical dip is also a viable strategy, particularly when

dealing with poor quality initial material.

Tissue culture and vine cuttings

Tissue culture and vine cuttings are other technologies to mass-produce plants that form healthy mini-tubers to

be used as seed material. They allow the elimination of major pests such as nematodes if they are planted on

nematode-free land. However, as for hot water and chemical treatment, viruses cannot be fully eliminated and

plants must be monitored for these symptoms and affected plants eradicated. Research on both new

technologies is ongoing at IITA to optimize the procedures. These include the identification of the most suitable

media for meristem culture and alternatives to rice husks as the rooting media for vine cuttings.

Kikuno, H.

Danny Coyne is a plant

nematologist currently

stationed at IITA-Tanzania.

Abiodun Claudius-Cole is a

nematologist and a visiting

scientist at IITA-Ibadan.

Hidehiko Kikuno is a yam

physiologist with IITA-Ibadan.

email: d.coyne@cgiar.org

A B CD

A. Main vine stem cut from the mother plant. B. Vine cutting, with a node and a leaf, excised from the

main stem. C. Vine cutting in the rooting medium. D. Harvested tubers from vine cutting. – H. Kikuno

Vine cuttings give a high multiplication rate without the use of tubers. Depending on the cultivar, size, and type of

mother plants, the multiplication rate of vines (about 20-50 times or more) and the size of tubers harvested will

both vary. The combination of tissue culture and vine cuttings gives even higher multiplication rates, rapid

growth, and clean tubers for seeds. However, there is a need for the validation of the technology with more

species and cultivars in different agro-ecological zones. Nevertheless, it is expected that this technology can be

simplified so that NARIs and seed producing farmers can apply it and produce healthy seed tubers (Kikuno,

2009).

Disadvantages: Tissue culture facilities are needed and the availability of rice husks for making carbonized rice

husks as the rooting media is limited in some areas where rice is not cultivated.

This Technical Innovation

Brief is published by:

SP-IPM Secretariat

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