Phenotypic and Genotypic Characterization of Race TKTTF of Puccinia graminis f. sp. tritici that Caused a Wheat Stem Rust Epidemic in Southern Ethiopia in 2013-14.

A severe stem rust epidemic occurred in southern Ethiopia during November 2013 to January 2014, with yield losses close to 100% on the most widely grown wheat cultivar, 'Digalu'. Sixty-four stem rust samples collected from the regions were analyzed. A meteorological model for airborne spore dispersal was used to identify which regions were most likely to have been infected from postulated sites of initial infection. Based on the analyses of 106 single-pustule isolates derived from these samples, four races of Puccinia graminis f. sp. tritici were identified: TKTTF, TTKSK, RRTTF, and JRCQC. Race TKTTF was found to be the primary cause of the epidemic in the southeastern zones of Bale and Arsi. Isolates of race TKTTF were first identified in samples collected in early October 2013 from West Arsi. It was the sole or predominant race in 31 samples collected from Bale and Arsi zones after the stem rust epidemic was established. Race TTKSK was recovered from 15 samples from Bale and Arsi zones at low frequencies. Genotyping indicated that isolates of race TKTTF belongs to a genetic lineage that is different from the Ug99 race group and is composed of two distinct genetic types. Results from evaluation of selected germplasm indicated that some cultivars and breeding lines resistant to the Ug99 race group are susceptible to race TKTTF. Appearance of race TKTTF and the ensuing epidemic underlines the continuing threats and challenges posed by stem rust not only in East Africa but also to wider-scale wheat production.

Assessing the association of severe malaria infection and ABO blood groups in northwestern Ethiopia.

BACKGROUND & OBJECTIVES: There is lack of adequate information on the association between severe malaria and some human genetic markers like ABO blood types. The study was undertaken to evaluate the association between severe malaria infection and ABO blood types among febrile patients attending Felegeselam Health Center, northwestern Ethiopia. METHODS: A total of 398 febrile patients were examined for malaria and tested for ABO blood groups in December 2011. The blood samples were collected by finger pricking, stained with Giemsa and slides were examined microscopically. ABO blood group was determined by agglutination test using agglutinating A and B monoclonal anti-sera together with parasite load count. Chi-square and ANOVA tests were used to assess the difference between frequencies and means, respectively. RESULTS: Out of 398 acute febrile patients, 201 (50.5%) were found to be infected with Plasmodium parasites. Of which 194 (48.74%) and 7 (1.76%) belong to Plasmodium falciparum and P. vivax, respectively. The distribution of ABO blood groups was O (46%), A (27.1%), B (23.1%) and AB (3.8%). The percentage of severe malaria with respect to blood group A, B, AB and O was found to be 40, 34.1, 14.3 and 5.1%, respectively. The association of severe malaria with non 'O' blood types was statistically significant (χ2 = 31.246, p <0.01). INTERPRETATION & CONCLUSION: The present findings indicate that individuals with blood groups A, B and AB are more susceptible for severe malaria infection than blood group O.