Screening Tomato Genotypes for Bacterial Wilt Disease (Ralstonia solanacearum) Resistance in Ghana

Thirteen-tomato genotypes were assembled from the USA, Taiwan and Ghana for screening for bacterial wilt resistance in two environments: in a screen house at Crops Research Institute, Kumasi, Ghana and in the field at a bacterial wilt hot spot at Bechem in the Brong-Ahafo region of Ghana. The bacterium, Ralstonia solanacearum was isolated using the serial dilution method on Nutrient Agar (NA) and aseptically cultured for inoculation. The bacterium was implicated as the causal organism of the bacterial wilt disease of tomato. A local check, Petofake and H7996 were used as susceptible and resistant checks respectively. Three genotypes, H7996, LA0442 and LA0443 demonstrated significant resistance stability in both experimental environments by recording significantly low wilt incidence and severity. H7996 was obtained from the World Vegetable Centre (WVC), Taiwan while the other two genotypes were collected from the University of California, Davis, USA. Apart from the highest yielding genotype LA 0442 that recorded 50.67 t/h, the rest recorded very low yields. The lowest yielding genotype AVTO 1713, recorded (12.67 t/h). Thus, the highest yielding genotype, LA 0442 over-yielded the lowest AVTO1713 by approximately 300%. It is instructive to note that LA0442, which was identified as a stable resistant genotype also recorded the highest yield. This result supports the potential of developing a resistant, high yielding variety using LA0442 as a parent. The future of the tomato industry in Ghana therefore looks promising.