Study of genetic determinism of harvest index in durum wheat (Triticum durum Desf) under semi-arid conditions

Out of six varieties of durum wheat (Triticum durum Desf.), two local varieties with a low harvest index and four others with high harvest indices and short straw imported from France were studied in a diallel cross. The experiment was done in a complete randomized block design with three replications. It was done at the Research Station of the Institute of Technical Big Cultures of Khemis Miliana, located in the semi-arid high Chelif Valley in Algeria. Before spikes emerged from the grains of the six varieties, we did a complete diallel hybridization between them. This resulted in 30 crosses. The heterosis that appeared in F2 of the harvest index in some hybrids is because the genotypes vary. Nefer variety located close to the parabola shows there is no transgression in character. The effects of additive are confirmed by the Hayman analysis in the harvest index. The most promising breeding stocks that can be used to improve the harvest index of durum varieties are Guem Goum Erkham, Hedba3 and Excalibur.Key words: Genetic determinism, Triticum durum Desf, harvest index

Norovirus GII.17 Predominates in Selected Surface Water Sources in Kenya

In this study, the prevalence and genotypes of noroviruses (NoVs) in selected water sources from rural, urban and refugee settings in Kenya were investigated. Ten litres each of river, household and borehole water was collected in rural (Mboone River), urban (Nairobi and Mutoine River) and refugee (Dadaab refugee camp) settings. NoVs were recovered from the water samples by a glass wool adsorption–elution technique and/or PEG/NaCl precipitation. Nucleic acid was extracted using the automated MagNA Pure platform. NoVs were detected with singleplex real-time reverse transcription-polymerase chain reaction assays and characterised by nucleotide sequence analysis. NoVs were detected in 63 % (25/40) of the selected water samples comprising GII (42.5 %), GI (2.5 %) and mixed GI/GII (17.5 %) positive samples. The prevalence of NoVs in the Mutoine River (urban area) was higher than in the Mboone River (rural area) (P = 0.0013). Noroviruses GI.1, GI.3, GI.9, GII.4, GII.6, GII.12, GII.16 and GII.17 were identified, with GII.17 accounting for 76 % (16/21) of the typed strains. The NoV GII.17 predominance differs to other studies in Africa and further surveillance of NoVs in clinical and environmental settings is required to clarify/elucidate this observation. As information regarding NoVs in Kenyan water sources is limited this report provides valuable new data on NoV genotypes circulating in environmental water sources and the surrounding communities in Kenya.The National Research Foundation, South Africa and the National Council for Science and Technology, Kenya: South Africa/Kenya Research Programme.http://link.springer.com/journal/12560hb2017Medical Virolog