Weed control in vegetable crops for small-scale commercial vegetable farmers in Kenya

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Genetic diversity and relationships of indigenous Kenyan camel (Camelus dromedarius) populations: Implications for their classification

The genetic diversity and relationships amongst the dromedary (Camelus dromedarius) populations are poorly documented. Four recognized Kenyan dromedary breeds (Somali, Turkana, Rendille, Gabbra) and dromedary from Pakistan and the Arabian Peninsula (Saudi Arabia, United Arab Emirates) were studied using 14 microsatellite loci. Phylogenetic analysis showed that Kenyan dromedaries are distinct from Arabian and Pakistani populations. Expected heterozygosity and allelic diversity values indicate that Kenyan dromedaries are less diverse than non-Kenyan populations. With the exception of the Somali population, the Kenyan dromedaries are poorly differentiated (average FST=0.009), with only one to two loci separating the Gabbra, Rendille and Turkana populations studied (P 2. Our results do not support the present classification of the indigenous Kenyan dromedary into four distinct breeds based on socio-geographical criteria. Instead, our results point to just two separate genetic entities, the Somali and a group including the Gabbra, Rendille and Turkana populations

Genetic diversity and relationship of indigenous Kenyan camel breeds: Preliminary results

Camels are important resource for the desert-dwelling communities. They are a source of income, milk and meat and often play an important sociocultural role in pastoralist societies. In order to help formulate a rational conservation, utilisation and Development policy for the species in Kenya, a diversity of Kenyan camel breeds is being studied using microsatellite markers. Preliminary results on the analyses of four breeds (Rendille, Gabra, Turkana and Somali) with 10 micro\92satellite loci are Reported here. Their relationships with dromedary and bactrian populations from the Arabian Peninsula and the Asian continent have been investigated. Genetic distances between Kenyan camel populations are low with the Rendille and Gabra camels being the most closely related breeds. Kenyan camels are genetically clearly distinct from the Asian and Arabian dromedary as well as from the bactrian camel. They are genetically less variable than non-Kenyan populations, possibly due to a lower number of initial individuals

Microsatellite typing reveals strong genetic structure of Schistosoma mansoni from localities in Kenya

Genetic diversity and population structure of seven populations of Schistosoma mansoni sampled in Kenya were assessed using five microsatellite markers. The mean number of alleles per locus, expected heterozygosity in Hardy-Weinberg equilibrium and pairwise FST values ranged from 5.2 to 10.7, 0.5-0.8 and 3.6-27.3%, respectively. These data reveal that S. mansoni populations in Kenyan have relatively high levels of genetic diversity and is significantly differentiated. Our data combined with information on biogeography support the hypothesis that the strong genetic structure in Kenyan schistosomes is as a result of limited gene flow and large population sizes. Resistance to anthelminthics has not been reported among the Kenyan schistosomes, we hypothesize that this is probably due to the very little gene flow among populations, thereby limiting opportunities for the spread of rare alleles that might confer resistance to the drugs

Individual-breed assignments in caprine populations using microsatellite DNA analysis

Genetic variability of 18 microsatellites in five Chinese goat breeds was characterized and then individual-breed assignments were implemented on the basis of microsatellite multi-genotypes. Although the low Gst value of 5.7% occurred among these breeds, the accumulated non-parental exclusion probabilities of 99.99% and the correct assignment percentage of 82% demonstrated that microsatellites were feasible for paternity testing and individual-breed assignments in caprine populations. All of loci showed high polymorphism except that MAF35 had only two alleles, and INRA0132 had potential null allele in these breeds. The non-parental exclusion probability per locus varied from 0.081 to 0.534 under case I for paternity testing and ranged from 0.161 to 0.699 under case II, respectively. Both of Excl 1 and Excl 2 were significantly correlated to the genetic diversity measures including genetic heterozygosity, polymorphism information content (PIC) and gene differential coefficients, and that suggested genetic polymorphism of marker provide enough information for microsatellite selection. In addition, the Bayesian method was proven to have superiority of the correct assignment percentage in comparison to gene frequency method and genetic distance methods, with the assumptions of locus-population Hardy–Weinberg Equilibrium and no linkage between loci. The correct assignment percentage were always higher in YC and Boer than other three goat breeds, implying assignment efficiency was positively relative to populations with greater uniformity and low population genetic variability. The correct assignment percentage rose with the increase of number of loci used, and it could reach 71.5% when nine microsatellites with the highest genetic polymorphism were combined together