Amplicon sequencing identified a putative pathogen, Macrophomina phaseolina, causing wilt in African eggplant (Solanum aethiopicum) grown in Tanzania and Uganda

African eggplant (Solanum aethiopicum L.) is one of the most common traditional vegetables in Tanzania and Uganda, but its productivity is severely affected by wilt diseases caused by a number of pathogens. Plant stem and root samples were collected in several fields from many neighboring diseased and healthy plants of the Gilo group in Tanzania and from the Shum group in Uganda to identify putative pathogens causing wilt on African eggplants. Through amplicon sequencing of sampled diseased and healthy tissues, we identified putative causal pathogens for the wilt symptoms. Wilting of S. aethiopicum in Uganda is most likely caused by the bacterial pathogen Ralstonia solanacearum whereas, in Tanzania, wilt is most likely caused by the fungal pathogen Macrophomina phaseolina, infecting roots. Infection of stems by Fusarium solani may also contribute to the wilt symptoms in Tanzania. Further artificial inoculation under controlled conditions confirmed that M. phaseolina can cause typical wilting symptoms on S. aethiopcium genotypes. The discovery of different putative causal agents of wilt in the crop demonstrates the need for site specific etiological analysis of wilt before developing and implementing effective control methods. Further research is needed to confirm the results and develop appropriate management measures against specific wilt pathogens

Climate change vulnerability and smallholder farmers’ adaptive responses in the semi-arid Far North Region of Cameroon

Climate change and variability contribute to exacerbating poverty and social unrest in poor countries. Therefore, it becomes important to assess vulnerability and adaptation measures to raise awareness and monitoring of climate change adaptation policy for better decision-making. This research examines how farmers perceive their vulnerability and how they respond to climate change in the semi-arid Far North Region of Cameroon. Using both quantitative and qualitative approaches, data on perceptions with regards to vulnerability and adaptation responses to climate change related hazards were collected based on expert opinions, individual farmers’ interviews, and focus group discussion. The qualitative data were triangulated with direct observations in the field. The results reveal that farmers are mostly concerned about drought and decrease in rainfall. Thus, they have mainly implemented behavioral and locally-made options such as short-cycle varieties, terrace farming, half-moon, and bunds, among others, to overcome water shortages. Nevertheless, these measures were not solely driven by vulnerability; the socioeconomic context might play a role. Moreover, farmers perceive a limited capacity to adapt to climate change, which suggests that the government and policy-makers should focus, not only on implementing planned adaptation strategies, but also on the improvement and promotion of farmers’ autonomous adaptation strategies