Rotylenchus wimbii n. sp. was found associated with finger millet in Kenya and is described based on light microscopy, scanning electron microscopy, and molecular information. Sequence analysis was performed on ITS, 18S, and D2-D3 of 28S of ribosomal DNA and COI of mitochondrial DNA. This new species is characterized by a moderate female body size of 0.6 to 0.8 mm, a continuous hemispherical lip region with four annuli, 3 to 4 irregular blocks on the basal lip annule, absence of longitudinal cuticular striations in anterior region, four lateral lines forming three equal bands which are areolated mainly at pharynx level, a robust stylet of 23 to 27 µm of which 45 to 53% is cone part, and with rounded to sometimes indented knobs, a secretory-excretory pore around level of pharyngo-intestinal junction, didelphic-amphidelphic reproductive system, vulva without distinct epiptygma, indistinct to empty spermatheca, tail usually truncated with 5 to 9 annuli, phasmids located at 7 to 17 annuli anterior to anus, and absence of males. Molecular phylogenies, in combination with species delimitation, supported the distinctiveness of Rotylenchus wimbii n. sp. and revealed some mislabeled Rotylenchus brevicaudatus sequences in GenBank.

Background and aim Fungal endophytes are commonly associated with plants, and are considered an important component of crop production. They can influence plant growth and tolerance to biotic and abiotic stresses. The aim of this study was to analyse and identify endophytic fungi associated with rice roots in irrigated and upland ecosystems in Kenya, as an inventory for a future search for biological control and growth promoting agents. Methods Fungi were isolated from the roots and selected based on culture characteristics. All selected isolates were sequenced using primers targeting the internal transcribed spacer (ITS) region, intergenic spacer (IGS) region and the gene encoding the translation elongation factor (TEF-1α). The species were determined by comparing their sequences with those of well characterised or type strains. Phylogenetic relationships among the species were used to identify their taxonomic groups, and distribution in the agroecosystems, especially for the Fusarium spp. Results Based on sequencing of the ITS region, 75 fungal isolates were identified as Fusarium-like, while the remaining 98 isolates were found to belong to different species representing other genera than Fusarium. A further analysis of the Fusarium spp., using concatenated IGS and TEF-1α sequences showed that these isolates belong to the Fusarium oxysporum (FOSC) and Gibberella fujikuroi (GFSC) species complexes. Within the FOSC isolates, a clear divergence was observed between isolates from irrigated and upland ecosystems, while in the GFSC this phenomenon was not observed. When the total number of species was considered, 27 species were identified in the irrigated ecosystems, while only 18 species were found in the upland ecosystems. Conclusions More fungal species were found in the irrigated ecosystems than in the upland ecosystems. We propose that flooding may affect the assembly of endophytic fungi in rice roots, however, other factors such as rice cultivars, geographical locations and soil types could also be important.

<p> </p><p><strong> </strong></p><p> </p><p><strong>Background. </strong>Carbon lost in form of carbon dioxide contributes to climate change corresponding to altered soil chemical properties and plant growth. Land-uses that minimize carbon loses are highly encouraged. Unfortunately, in the Kakamega-Nandi Forest Complex, the Kenyan government continues to promote shamba systems (now Plantation Establishment for Livelihood Improvement Scheme) where the forest adjacent communities are allocated bush land plots to provide land for small-scale agriculture, cash crop farming and planting of tree seedlings for a specified period of time inside the forest. <strong>Objective. </strong>This study analyzed six land-uses and their effect on the dynamics of soil chemical parameters using landsat images and recent soil geochemical surveys. <strong>Methodology. </strong>Land cover and vegetation changes were determined using a series of multispectral Landsat images. A total of seven sets of image datasets were downloaded from the Glovis web portal (<a href="http://glovis.usgs.gov/">http://glovis.usgs.gov/</a>) for the years 1985 to 2015 with the cloud cover ranging from 1 to 10% taken in the dry season. The land-use/cover classification scheme adopted was based on expertise knowledge and literature of land-use/cover activities.  <strong>Results. </strong>The results show that (i) small-small agriculture has increased while bush-land has decreased between 1985 and 2015; (ii) smallholder farming of maize, pasture and sugarcane depleted soil organic carbon whereas perennial tree plantations (regenerated forests) increased soil carbon stocks; (iii) nitrogen decreased in all tested land-uses except in maize plantations; (iv) phosphorus remained unchanged in all land-uses, potassium significantly decreased in tea plantations while sugarcane and regenerated forests land-uses had decreased soil calcium stocks. <strong>Implications. </strong>The study provides evidence for the review of the shamba system. <strong>Conclusion. </strong>The study has shown that land-use changes through the application of the shamba system alter the dynamics of soil chemical parameters key among them are soil organic carbon, nitrogen and calcium. Cultivation of annual crops decreases soil carbon stocks which may lead to an influx of carbon dioxide in the atmosphere and increased vulnerability to climate change.</p>

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