Farmers are more likely to accept yellow/orange fleshed cassava due to the growing popularity/acceptance of orange-fleshed sweet potatoes,Evaluation and selection of cassava varieties for high beta carotene content

1. Development and Evaluation of Yellow
fleshed Cassava clones in Tanzania,Uganda
and SARRNET Countries
E. Kanju1 and P. Ntawuruhunga2
1IITA-Tanzania
2IITA-Malawi
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

2. Introduction
•Thirty percent (30%) of African children under five are
Vitamin A deficient
•Bio-fortification offers more cost-efficient treatment than
medical supplements
•Yellow-fleshed cassava are not commonly found
among the local germplasm
•Very few farmers are aware of yellow-fleshed cassava
genotypes
•Farmers are more likely to accept yellow/orange
fleshed cassava due to the growing
popularity/acceptance of orange-fleshed sweet potatoes
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

3. Materials and Methods
• Sources
– Selections among F1 seedlings
– TC materials from IITA-Ibadan (Uganda)
– Crossing blocks established (Namulonge and Naliendele)
• Selection criteria
– Yellow fleshed colour – visual selection (1 – 9 scale)
– High dry matter (≥30%)
– Disease resistance/tolerance
– Low CnP
– Mealiness
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

4. Achievements
• Tanzania
– All the clones selected (23 in CET
2006/07) were susceptible to
CBSD
– None of the clones selected was
mealy
– Colour score range 3 - 5
– Seeds from CBSD tolerant parents
planted in 2009
• Uganda
– 44 clones at AYT at Namulonge in
2009 (high CMD and CBSD
pressure)
– Colour score range 3 - 5
– 21 clones introduced from Ibadan
are at CET at Serere
– Private partner interested and
involved (UgaChick) International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

5. 3 Evaluation and selection of cassava
varieties for high beta carotene content
• In Angola 18 yellow root clones from IITA introductions
are in a clonal evaluation trial at Malanje and Kwanza
Norte and will be harvested in November.
• Additional clones with high beta carotene content are
being selected from the 2007/08 SN.
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

6. • In Malawi quantitative analysis for root beta carotene
content started mid August (8 MAP).
• Analysis is being conducted at IITA/SARRNET
biochemistry lab.
• Clone 98/2132 has the highest (7.15 ( g /g) levels of
beta carotene followed by 01/1413, 01/16960, 01/1371
and 01/663 with levels of 3.03 to 4.69 g /g.
• The checks (white-flesh), Mbundumali and NDL90/034,
had the lowest levels (<0.05 g /g), confirming the fact
that white-fleshed cassava are poor sources of beta
carotene.
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

7. • In Zambia the yellow root clones, 99/2987, 01/1224,
01/1380 and 01/1115, are still in the field at Mansa
and will be evaluated for agronomic performance and
root beta-carotene content at harvest in December.
• In Mozambique, 82 clones (16 yellow root and 66
high protein content) are in AYT and UYT at Umbeluzi
and Mocuba Research Stations. Will be analyzed for
beta carotene and protein content at harvest in
December.
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org

8. Way Forward
• Develop source population for yellow-fleshed roots
• Identify parents with high breeding values for deep yellow-
fleshed roots, high dry matter content, low CnP and
resistance to CMD and CBSD for use in crossing blocks
• Start farmer participatory evaluation to capture farmers’
preferences
• Quantify levels of beta carotene in selected clones (target is
clones with 15μg/g)
• Evaluate suitability of yellow-fleshed roots for use in different
products
• Germplasm introduction (esp. mealy deep yellow/orange
parents)
International Institute of Tropical Agriculture – Institut international d’agriculture tropicale – www.iita.org