Management of bacterial (Ralstonia solanaceerum) wilt in tomato (Solanum lycopersicum L.) using resistant African eggplant (Solanum spp) rootstocks T. NIKUZE, E. M. ATEKA, W. O. OWINO AND J. AMBUKO 6/June/2018

INTRODUCTION Tomato is an economically important horticultural crop in Kenya Progressive decline in tomato production 6/June/2018

Cont… Increased cost of production and reduction in household income Constantly attacked by BW Wide host range and widespread Mitigated through use of resistant varieties 6/June/2018

Performance of tomato in Kenya 2012 – 2015 Year Area (000) Ha Volume (MT) Value (000, Ksh) 2012 19 364 103 2013 21 384 116 2014 24 400 118 2015 25 410 120 6/June/2018

Objectives To determine phenotypic reaction of African eggplant accessions to bacterial wilt infection To identify resistant markers for bacterial wilt in different accessions of African eggplant 6/June/2018

Materials and Methods 1. To determine the phenotypic reaction of African eggplant accessions to bacterial wilt infection 6/June/2018

Bacterial wilt status of experimental field Soil sample Number of colonies Population density (cfu/ml S1 177 1.6 x 107 S2 148 5.9 x 106 S3 154 9.4 x106 6/June/2018

Trans-Planting Eggplant seedlings Inoculation Field Greenhouse 6/June/2018

Results Healthy plant (A), bacterial wilt symptoms (B, C and D), E, F and G BW oozing from plant sections a D b B c Oozy stem F E 6/June/2018 G

Cont… Morphological characteristics on TZC (Kelman) media 6/June/2018

Reaction trends 6/June/2018

Trends cont… 6/June/2018

Trends cont… 6/June/2018

Trends cont… 6/June/2018

Trends cont… 6/June/2018

Materials and methods 2. To identify resistant genes for bacterial wilt in different accessions of African eggplant 6/June/2018

DNA-extraction CTAB PCR 6/June/2018

Results 6/June/2018

Cont….. 6/June/2018

A1 A2 A A3 B1 B B3 6/June/2018 B2

Discussion and Conclusion There was difference in response to infection Various mortality at different time point No wilting symptoms in Accession RV100332 and resistant markers Accession RV100445 did not react to BW and carried 5 SSR markers Morphological characteristics of Ralstonia after isolation 6/June/2018

Cont… Resistant markers were present in thirty accessions There is association between accessions and origin S. aethiopicum and S. anguivi good source of resistant genes Resistant markers will help breeders to develop resistant tomato varieties to BW Resistant accession can be used as rootstocks in management of BW 6/June/2018

References Bi-hao, C. Jian-jun, L., Yong, W. and Guo-ju, C.2009. Inheritance and identification of SCAR marker linked to bacterial wilt-resistance in eggplant. African Journal of Biotechnology , 8(20), pp. 5201-5207. Caguiat, X.G.I. and Hautea, D.M.2014. Genetic Diversity analysis of eggplant (solanum melongena l.) and related wild species in the philippines using morphological and ssr markers. sabrao Journal or Breeding and Genetics, 46(2), pp. 183-201. Castillo, J. A. and Greenberg, J. T. 2007. Evolutionary Dynamics of Ralstonia solanacearum." Applied and Environmental Micribiology, 73(4), pp. 1225-1238. Lebeau, A., Gouy, M., Daunay, M. C., Wicker, E., Chiroleu, F., Prior, P., Frary, A. and Dintinger, J. 2013. Genetic mapping of a major dominant gene for resistance to Ralstonia solanacearum in eggplant. Theor Appl Genet, Volume 126, pp. 143-158. Muthoni, J., Shimelis, H. and Melis, R. 2012. Management of Bacterial Wilt [Rhalstonia solanacearum Yabuuchi et al., 1995] of Potatoes: Opportunity for Host Resistance in Kenya. Journal of Agricultural Science, 4(9), pp. 64-78. 6/June/2018

THANK YOU 6/June/2018