1. Combined genetic distance analysis revealed by morphological and AFLP markers of cassava (Manihot esculenta Crantz) breeding parents in Mozambique
AM Zacarias da Silva, MT Labushagne, E Koen and EE Kanju
First Scientific Meeting of the Global Cassava Partnership
21-25 July 2008, Ghent, Belgium

2. BACKGROUND INFORMATION
Importance of cassava in Mozambique
Major source of calories
Second major crop after maize
Staple food for rural communities
Food security crop
One of most widespread produced by farms (72%)
Small-scale farmers represent 99%, intercrop
Production 11.5 million tonnes year

3. CMD +
CBSV

4. Uses Root Human consumption (fresh, flour, gari) Animal Processing
Mostly manual: dry pellets/flour and gari
Initiatives for composite flour
Leaves as vegetable (source of vitamin)
Informal Market predominant
Mozambique Cassava Strategy
was developed (2007)

5. CONSTRAINTS TO PRODUCTION

6. BREEDING OBJECTIVES
Resistant to cassava brown streak disease (CBSD) and cassava mosaic disease (CMD)
High yielding varieties
Selection for clones desired traits for farmers and emerging market (e.g. high quality flour, rale (gari) and starch)
Adaptation to main production environments in the country
Assess of genetic diversity cassava breeding parents genotypes by means of morphological and AFLP analysis

7. MATERIALS AND METHODS (cont)
4 IITA clones resistent to ACMV
13 local entries
Roots traits desired by farmers
CBSV leaves symptoms
Tolerant to CBSV root necrosis (scale 1 to 5)

8. Genebank mantained in Nampula, Mozambique, morphological traits recorded
Leaves: unexpanded and mature leaf colour
Pubescence
Lobe: number, shape, width and length
Petiole: length and colour
Stem: mature and apical colour
Branch: habit, level and height of first branch
Plant height
Root: inner skin, cortex and pulp colour; shape and peeling

9. Fresh leaf samples collected, packed in tissue mosture, freeze-dried (-60°C) and preserved (-70°C) at UOVS - SA
DNA extraction: Dellaporta et al. (1983)
AFLP analysis: Voz et al. (1995) modified by Herselman (2003) P

10. Results

11. Genetic distances for morphological (above diagonal) and a combination of AFLP and morphological (bellow diagonal) based on Dice similarity coefficients for 17 characterised accessions
Nikwa
TMS
Chigo
Mulal
Mocu
Nachi
Mucu
IMM
Munh
Namu
Muna
MZ891
MZ896
Likond
Macia
Nxink
Baad
0.462
0.467
0.357
0.824
0.370
0.519
0.765
0.737
0.581
0.417
0.833
0.706
0.750
0.571
0.801
0.333
0.375
0.455
0.400
0.533
0.364
0.308
0.105
0.500
0.273
0.810
0.829
0.526
0.421
0.539
0.600
0.435
0.125
0.316
0.385
0.770
0.816
0.822
0.167
0.353
0.471
0.235
0.286
0.735
0.727
0.762
0.667
0.522
0.813
0.714
0.751
0.791
0.808
0.797
0.802
0.625
0.444
0.300
0.348
0.381
0.811
0.800
0.807
0.909
0.609
0.250
0.480
0.476
0.783
0.805
0.738
0.804
0.823
0.733
0.745
0.794
0.844
0.878
0.828
0.296
0.742
0.790
0.772
0.695
0.752
0.771
0.803
0.789
0.710
0.722
0.429
Munam
0.814
0.817
0.723
0.773
0.799
0.827
0.118
0.621
0.320
0.775
0.821
0.798
0.753
0.841
0.774
0.867
0.707
0.779
0.843
0.766
0.835
0.916
0.784
0.815
0.792
0.754
0.780
0.812
0.788
0.851
0.615
0.793
0.726
0.782
0.820
0.852
0.795
0.709
0.778
0.806
0.546
Baadje
0.749
0.739
0.711
0.685
0.725
0.760
0.719
0.756
0.746
Nikwa=Nikwaha, TMS=TMS 30001, Chigo=Chigoma mafia, Mulal=Mulaleia, Mocu=Mocuba, Nachi=Nachinaya, Mucu=Mucudo moevia, IMM=IMM 30015, Munh=Muhaça, Namuh=Namuhiripwi, Munam=Mwanamwahula, MZ891=MZ 89001, MZ896=MZ 89186; Likond=Likonde, Macia =Macia 1, N’xink= N’xinkole

12. Combined AFLP and morphological characterisation of 17 cassava accessions with the aid of NTSYS computer package, Dice similarity coefficient and UPGMA clustering

13. PCoA plot for characterisation of 17 analysed cassava accessions using combined analysis with the aid of NTSYS computer package

15. CONCLUSIONS AND RECOMMENDATIONS
Relatively low levels of correlation were found between the morphological versus AFLP and combined analysis, but strong correlation was found between AFLP and combined analysis.
In practice, the results support the idea of combining both methods, to obtain a more accurate idea of the accession
AFLP and morphological analysis were complementar and useful to determine distinctiveness among accessions.

16. The use of molecular markers allowed the identification of the unique accessions to be used in the breeding programme.
The AFLP and morphological analysis did not group the accessions according to geographical origin.
Further studies should involve larger numbers of accessions with information about their pedigree for a clear picture of diversity in the country and explore the role of different methods
Introductions of new germplasm to increase genetic diversity

18. AKNOWLEDGEMENTS AGRA University of Free State
Agricultural Research Institute of Mozambique (IIAM)

19. THANK YOU VERY MUCH “MUITO OBRIGADO”