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Reactive iron (Fe) oxides and sheet silicate-bound Fe in reservoir rocks may affect the subsurface storage of CO2 through several processes by changing the capacity to buffer the acidification by CO2 and the permeability of the reservoir rock: (1) the reduction of three-valent Fe in anoxic environments can lead to an increase in pH, (2) under sulphidic conditions, Fe may drive sulphur cycling and lead to the formation of pyrite, and (3) the leaching of Fe from sheet silicates may affect silicate diagenesis. In order to evaluate the importance of Fe-reduction on the CO2 reservoir, we analysed the Fe geochemistry in drill-cores from the Triassic Stuttgart Formation (Schilfsandstein) recovered from the monitoring well at the CO2 test injection site near Ketzin, Germany. The reservoir rock is a porous, poorly to moderately cohesive fluvial sandstone containing up to 2–4 wt% reactive Fe. Based on a sequential extraction, most Fe falls into the dithionite-extractable Fe-fraction and Fe bound to sheet silicates, whereby some Fe in the dithionite-extractable Fe-fraction may have been leached from illite and smectite. Illite and smectite were detected in core samples by X-ray diffraction and confirmed as the main Fe-containing mineral phases by X-ray absorption spectroscopy. Chlorite is also present, but likely does not contribute much to the high amount of Fe in the silicate-bound fraction. The organic carbon content of the reservoir rock is extremely low (

Honey bee population worldwide is dwindling due to a number of interrelated factors among them pathogens such as viruses, bacteria, fungi and metazoan parasites. These factors negatively affect agricultural production as well as the apiculture industry which is dependent on a seasonal abundance of honey bees year-round. As a result, food security and livelihood is compromised due to loss of pollinators. Majority of viruses infecting honey bees are positive-sense single-stranded RNA viruses of the order Picornavirales. The economically important viruses of bees in this order belong to family Dicistroviridae and Iflaviridae. Paenibacillus larvae and Melisococcus plutonius are bacteria known to cause bee brood diseases. This studyaimed at identifying the viruses circulating in Kenyan honey bee colonies using next generation sequencing. Ribonucleic acid (RNA) was extracted from sixteen libraries and was used in cDNA synthesis using superscript II. The cDNA converted to dsDNA using Klenow reaction and used in amplification. 454 pyro sequencing was performed on genome sequencer FLX system. The resultant single reads were analyzed using CLC Genomic workbench. The reads were mapped on the full genomes of the identified viruses and then de novo assembled. The resultant contigs were interrogated using basic alignment search tool (BLAST) on national center for biotechnology information (NCBI) database. The contigs were exportedto MEGA6 and used in phylogenetic analysis. The viruses identified belonged to family Iflaviridae and included deformed wing virus, Kakugo virus and Varroa destructor virus-1. Melissococcus plutonius and Enterococcus faecalis were also detected. Of the sixteen libraries sequenced, two libraries; Busia_adult andSiaya_brood reported the incidences of iflaviruses while five libraries had reads matching with M. plutonius and E. faecalis. There is need for a strategy in place for the management of bee diseases to enhance bee health and quality of hive products.Key words: Bee viruses, Paenibacillus larvae, Melissococcus plutonius, Iflavirus, Next generation sequencing

Yields of commercially important crops in Kenya are often far below their potential. Amongst the possible reasons for such low yields may be the ecosystem degradation that can be expected to have negative impacts on pollinator presence in cropland, and the consequent food security issue for smallholder farmers who depend on these crops for their livelihood. Our study was carried out to assess the potential pollination deficit of French beans (Phaseolus vulgaris L.), a major export vegetable crop in Kenya grown by small-scale farmers. Sufficient pollination of French beans likely results in high seed set and uniform heavier green pods. Such pods get the highest grade while malformed pods are unmarketable, reducing family income. We hypothesized that pollination success was linked to the abundance and diversity of large pollinators, itself associated with the proximity to natural habitats. Flower visitors to French beans were sampled in 2011 and 2012 in ten farmer-managed plots, five within 200 m from the edge of Mt. Kenya forest and five farther away, more than 1000 m. Each plot measured 760 m2 and was planted at the same time, with the “Julia” variety. Flowers were observed for 2 h in each plot once weekly for three weeks at peak flowering from 0900-1100 h in the morning and 1200 – 1400 h in the afternoon on alternate days. Honey bees (Apis mellifera) were the most abundant visitors of French bean flowers followed by carpenter bees (Xylocopa spp.) and leafcutter bees (Megachile spp.). Significantly higher numbers of leafcutter bees were recorded on farms far to the forest. There was no significant difference in honeybee abundance among the study sites, probably because apiaries and wild colonies are located across the landscape. French bean yield was significantly correlated with the mean abundance of carpenter bees in 2011. This suggests the possible occurrence of pollination deficit in French beans where the density of carpenter bees is insufficient, which was reflected by the high variability of yields in the farmland. We advocate that area-wide management and conservation of carpenter bees should be initiated to support French bean farming in the area.

Honey bees (Apis mellifera L.) are frequently employed in pesticide toxicity testing either as a representative species (i.e., surrogate) for pollinating insects (such as in the European Union (EU)) or in other cases to represent other non‐target terrestrial invertebrates. Bees exhibit a wide range of social behaviors, but depending on their interdependency, bees can be broadly divided into two groups: social or solitary. Most of the non‐Apis bee toxicity testing conducted in Europe has been on bumble bees, and in particular Bombus terrestris, which is the main species used for commercial pollination. It is clear that non‐Apis bees play an important role in supporting diverse plant communities, and an increasingly important role in agriculture. They differ from honey bees in their biological characteristics, which consequently may make them subject to unique exposure routes, as well as unique challenges when it comes to risk management.

La protection des cultures maraîchères avec des filets anti-insectes en climat tropical au Bénin et au Kenya s'est avérée extrêmement efficace contre les principaux ravageurs tant au stade pépinière qu'en grande culture. Cependant, les filets ne protègent pas toujours suffisamment les cultures contre les insectes piqueurs comme les pucerons et les aleurodes. L'ouverture des filets en milieu de journée peut être une alternative pour conserver l'action des ennemis naturels et réduire l'impact négatif sur le microclimat. L'efficacité des barrières physique et visuelle peut aussi être complétée par une barrière chimique sous la forme d'un composé répulsif imprégné dans le filet. Les petits producteurs qui ont adopté les filets au Bénin et au Kenya ont réduit le nombre d'applications d'insecticide de 70 à 100 % tout en augmentant leur production en quantité et en qualité. L'analyse coût-bénéfice de la technologie a montré que des filets anti-insectes ont multiplié par 3 le taux de rentabilité de la culture de chou par rapport aux pratiques conventionnelles des petits producteurs. Du fait de sa compatibilité avec les méthodes de lutte biologique, cette technologie ouvre une voie prometteuse pour développer une production maraîchère agroécologique.

The aim of this research was to study spatial distribution of flower thrips on French beans (Phaseolus vulgaris L.) in Kenya. Their build up and seasonal population dynamics was monitored using sticky blue colour traps and sampling of leaves and flowers in two seasons in 2002. Thrips infested French beans from the second week after crop emergence. Their population peaked at peak flowering. The sticky trap catches were linearly related to the actual presence of thrips on the crop and could estimate population build up of adult thrips on leaves and flowers. On the plants, most adults were on flowers. Larvae mainly inhabited leaves, buds and pods. The two thrips species, Frankliniella occidentalis (Pergande) and Megalurothrips sjostedti Trybom were spatially separated. The former colonized lower-canopy leaves and early flowers while the latter inhabited middle-canopy leaves and mature flowers. Overall, M. sjostedti was less than 5% of the total thrips population, implying that F. occidentalis was the main thrips pest of French beans. This study suggests that French bean growers should monitor thrips population before initiating any control measure. In addition, they should commence thrips control early, at pre-flowering, using larvicides to reduce the thrips pool and their migration to flowers. A combination of monitoring with sticky traps and proper sampling would contribute to sustainable thrips management., El presente estudio trató de determinar los patrones de alimentación del trips de la flor como plaga de la judía (Phaseolus vulgaris L.) en Kenia. El incremento de la población y grado de infestación de trips se evaluó usando trampas de adherencia azules en hojas y flores durante dos estaciones en el 2002. Los trips infestaron a la judía desde la segunda semana después de la emergencia del cultivo, y alcanzaron una población máxima durante la floración. Conteos en las trampas de adherencia mostraron una correlación lineal con la presencia de trips en el cultivo y pueden servir de referencia del crecimiento de las poblaciones de trips adultos en hojas y flores. En la planta, la mayoría de adultos se encontraron en las flores, mientras que las larvas se concentraron en las hojas, brotes y vainas. Las especies de trips Frankliniella occidentalis (Pergande) y Megalurothrips sjostedti Trybom se mantuvieron separadas en el espacio: mientras que la primera prefiere las hojas inferiores del dosel y las flores jóvenes, la segunda suele optar por las hojas de en medio del dosel y flores maduras. M. sjostedti representa menos del 5% de la población total de trips, lo que hace de F occidentalis la principal peste de la judía. El estudio sugiere que los agricultores deben monitorizar la dinámica poblacional de los trips antes de efectuar medidas de control, y complementariamente, deberían usar larvicidas antes de la floración previendo su posterior migración a las flores. Una adecuada combinación entre vigilancia y adecuada toma de muestras contribuiría al control sostenible de las poblaciones de trips.

A field experiment was carried out in 2004 and 2005 to identify the diversity of sunflower (Helianthus annuus L.) pollinators and their influence on seed yield in Makueni district, a semi-arid area in Eastern Kenya. Insect flower visitors were recorded, pollen counted from their body and pollination efficiency index for each visitor determined. Seed yield from plots where insect visitors had access to and where they were denied access was compared. The proportional difference of yield from this pollination scenario was used to estimate monetary net-gain by farmers that could be attributed to insect pollination. In total, individuals belonging to 14 insect species were observed visiting sunflower floral heads. These included six Lepidopteran species, five Hymenopteran species, two Dipteran species, and one Coleopteran species. Apis mellifera L. was the most frequent visitor and had the highest pollination efficiency index. Plots where insect visitors had access produced on average 53% more seed yield compared with plots where insect visitors were excluded. This translates to a net monetary benefit of 51% of the total annual market value of sunflower, accruing to farmers in Makueni district in 2005 due to insect pollination., Se condujo un experimento de campo entre 2004 y 2005 para determinar la diversidad de polinizadores de girasol (Helianthus annuus L.) y su influencia en el rendimiento de semillas en el distrito Makueni, una región semi-árida del Este de Kenia. Se identificaron los insectos vectores de polinización y se contó el polen adherido a sus cuerpos, a fin de determinar el índice de eficiencia de polinización de cada especie. Se comparó el rendimiento de semillas entre las parcelas visitadas y no visitadas por los vectores de polinización. Se estimó la ganancia monetaria neta de los campesinos atribuida a la polinización por insectos. En total, se observaron 14 especies de insectos visitando girasoles, que incluyeron 6 especies de Lepidópteros, 5 de Himenópteros, 2 de Dípteros y un Coleóptero. Apis mellifera L. fue la especie visitante más frecuente y obtuvo el mayor índice de eficiencia de polinización. Las parcelas a las que los insectos tuvieron acceso produjeron como promedio un 53% más semillas que las parcelas de las que los insectos fueron excluidos. Esto implica un beneficio monetario neto del 51% del valor total del mercado anual de girasol, debido a polinización por insectos, para los campesinos del distrito Makueni en 2005.

A collaborative sea cruise in the Vietnam waters of the South China Sea was conducted in the postmonsoon (21 April to 5 June, 1999) period on board MV SEAFDEC. The nanoplankton from 21 sampling stations consisted of 134 taxa comprising predominantly of centric nanodiatom (29 species), pennata nanodiatom (40 species) and dinoflagellate (65 species). Among the minute plankton collected, three species of nanodiatom (Minidiscus comicus, M. chilensis, M. trioculatus) and numerous dinoflagellate species were present. The pennate nanodiatom comprised of the species of Asterionella, Psammodiscus and Amphipleura ranging from 5.25 x 102 to 1.67 x 104 cell/L; all which were