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Aflatoxins are known to cause devastating acute and chronic effects in humans and animals. The objective of the study was to determine the influence of postharvest practices and storage conditions on aflatoxin contamination in maize in two counties. Aflatoxin levels in 144 maize samples from different maize storage conditions were determined. While sampling, a structured questionnaire was also administered to evaluate farmer’s postharvest practices. Makueni County had the highest percentage of aflatoxin positive samples with up to 174 ppb attributed to the long storage under unfavourable conditions. On the other hand, Baringo County had lower positivity associated with the harvesting season at the time of sample collection. The type of storage condition had a significant effect on the extent of contamination and accounted for 11% of the variation (R 2 = 0.11). Gunny bags were the most common type of storage condition and had the highest level of contamination in both the counties. Metallic bins had the lowest level of contamination. Aflatoxin G1 and G2 were predominant in samples from Baringo County, while aflatoxin B1 and B2 were predominant in samples from Makueni County. The study concluded that the type of storage condition significantly contributes to the aflatoxin contamination in the stored maize. Proper drying of maize to the recommended moisture content and subsequent storage in hermetic structures will reduce the cases of aflatoxin contamination.

Abstract Background As much as local communities have employed traditional techniques of preservation to enhance availability and utilization of cowpea leaves, the efficiency of these techniques in achieving food security need to be established. The current study sought to document trends and constraints of utilization of preserved cowpea leaves in the arid and semi-arid lands (ASALs) in order to overcome of seasonal availability of the vegetable. Method A mixed method convergent design that included household survey of randomly sampled cowpea producing households and focus group discussion and key informant interviews with stakeholders in the ASAL areas of Kitui and Taita Taveta Counties of Kenya was conducted. Results The study found that the utilization of preserved forms of cowpea leaves in the in-season was by 58% of the respondents. Three quarters (73.6%) of the households could not get the vegetables from their own sources during scarcity, whereas 25% did not consume the vegetables at all at such times. The preserved forms of the vegetables was utilized among 24.0% of the households, with significantly (p

Pesticide application in agricultural and residential areas is a worldwide practice. However, human pesticide poisoning and environmental pollution through pesticide residues remain a challenge in the developing world. The present study investigated the intensity of pesticide application in large-scale farms in Trans-Nzoia County to screen and prioritize the pesticides for potential human health and environmental risks. A cross-sectional survey involving 348 farmers was conducted in the study area, and data was analyzed using SPSS. Environmental Exposure Potential (EEP) and Toxicity Potentials (TP) were analyzed from the Pesticide Properties Database (PPDB). Majority (99.4%) of the farms surveyed apply various pesticide classes that include: organophosphates (34.78%), neonicotinoids (15.22%), carbamates (10.87%), pyrethroids (10.87%), organochlorines (8.7%), triazoles (6.5%), copper-based (4.34%), avermectines (2.17%), triazines (2.17%), and amidines (2.17%), with the use of organic manures (26.3%). Despite the high prevalence of pesticide application, only 48.28% of farms conduct soil quality monitoring, 77.3% of whom do not have clear records and schedules for conducting periodic soil analyses. There was a strong positive correlation between the acreage of operation and the use of herbicides in weed management (r = 0.77; p ≤ 0.05). In relation to degradation in the environment, 18.42% of the pesticides applied in the study area were persistent in soil sub-systems while 31.58% are persistent in water. Of the pesticides applied, 18.42% had high chances of bioconcentration in living tissues, 10.53% and 13.16% had the potential of contaminating groundwater and surface water resources, respectively. The ranked-order human toxicity potential associated with the used pesticides were teratogenicity (31.58%), neurotoxicity (28.95%), endocrine disruption (7.9%), carcinogenicity (7.9%), and mutagenicity (2.63%). However, 10.53% of the pesticides possess multiple toxicity potentials. Some farmers (53.70%) surveyed were not aware of the negative environmental impacts of pesticides with 59.50% having prior training on the use and handling of pesticides. Despite the availability of Personal Protective Equipment (PPEs) on larger farms, 31.9% of the farm workers do not adhere to their use during pesticide application. In conclusion, there is low awareness among farmers of human health and environmental risks associated with pesticide application. The study recommends training of farm managers, farm owners, and farm workers on pesticide handling and associated health and environmental effects.

The levels of acrylamide intake because of potato crisps consumption remains unknown in Kenyan context. This study assessed the exposure to acrylamide because of consumption of potato crisps in Nairobi, Kenya. A cross-sectional survey was carried out among 315 crisps consumers in Nairobi, and consumption patterns were collected using a pre-tested structured 7-day recall questionnaire. A total of 43 branded and 15 unbranded potato crisps samples were purchased in triplicates of 100 g and acrylamide was quantified using a gas chromatograph with a flame ionization detector. Consumption data were combined with the data on acrylamide contents from which dietary acrylamide intake was calculated using a probabilistic approach based on @Risk TopRank 6 risk analysis software for excel. The mean estimated acrylamide intake was 1.57 µg/kg body weight (BW) per day while the 95th (P95) percentile was 5.1 µg/kg BW per day, with margins of exposures (MOE) being 197 and 61, respectively. The intake of acrylamide was significantly (P < 0.05) higher in unbranded crisps with a mean value of 2.26 and 95th percentile of 6.54 µg/kg BW per day, MOE being 137 and 47, respectively. There were extremely lower MOE indicating higher exposure to acrylamide by the consumers mainly because of the higher acrylamide contents in potato crisps, and hence the need for mitigation measures.

This paper aims to contribute to the understanding of the resultant effects of the new Coronavirus which is known to cause a Severe Acute Respiratory Syndrome in humans (SARS-CoV-2 better known as COVID-19) on food security and household livelihoods in Kenya. This is achieved by providing a comprehensive literature review on past global epidemics, pandemics and natural hazards and disasters; and their effects on food security and household livelihoods. The study reviews articles and reports that have widely discussed the effects of other epidemics that have occurred in contemporary times on food security and household livelihoods. The selection of the materials used in the study was based on authenticity and relevance. The observed impacts of the coronavirus pandemic and previous epidemics, pandemics and natural hazards and disasters call for policy measures to curb future occurrences. Countries' preparedness for pandemics is crucial to prevent adverse economic effects and loss of human lives. There is also a need to put in necessary measures to ensure the sustainability of resources, strengthen infrastructure and food systems to avoid or minimize food crises in the future.

Cowpea (Vigna unguiculata) leaves are nutritious indigenous vegetables that are produced and consumed among local communities in Kenya. However, seasonal production limits their utilization. The study investigated the changing trends in the consumption and utilization of cowpea leaves among cowpea producing households in arid and semi-arid land (ASAL) areas. A cross-sectional survey of randomly selected households producing and consuming cowpea leaves was carried out in Eastern and Coastal ASALs of Kenya to determine the trends and constraints in the production and utilization of the vegetable, thus evaluating its efficiency as a food security crop. The average household production in a season was found to be 3.03 ± 0.9 of 90 kg bags. Lesser severity of the constraints, poor soils, drought, lack of access to seeds and massive spoilage with an odds ratio of 0.4, 0.9, 2.0 and 2.3, respectively, significantly (p < 0.05) predicted the production quantities among households, R2 = 0.21. The study also found that the reliance on own production among households for sourcing the leaves in-season and off-season was 97.5% and 24.9%, respectively. The households consumed the leaves in boiled (87.5%), sundried (27.5%) or blanched (13.6%) forms. Households in the coastal ASALs significantly (p < 0.05) consumed more of dried forms (odds ratio: 3.3) but less of boiled ones (odds ratio: 0.1) than those in the Eastern parts. Households that had more members or a female deciding the food to be bought had significantly (p < 0.05) higher frequency of consumption of cowpea leaves. Marketing challenges, lack of access to inputs and inadequate postharvest technologies for preservation of the vegetables constrained the production and utilization of cowpea leaves. In order to promote the availability and utilization of cowpea leaves both in and out of season, accessibility of good quality seeds and postharvest management are necessary.

Infestation of cereals such as wheat by pathogenic Fusarium species (Fusarium spp.) is associated with over 25% weight loss of the grain and accumulation of hazardous mycotoxins. Potential management strategies against the pathogens include the development of more resistant wheat genotypes and the development of rapid and accurate Fusarium spp. identification methods, among other control measures. This study evaluated the toxigenic potential in populations of Fusarium spp. isolated from seeds of locally developed wheat genotypes and levels of fumonisins in the grains at harvest in three counties in Kenya. The sampling of the wheat grains took place between September 2016 and October 2017. Determination of toxigenic potential was PCR based using Tri13F/Tri13DONR and FUM1F/FUM1R specific primer pairs while detection of fumonisin levels was done using Total Fumonisin Assay 0.25/5.0 ELISA kit. Data were analyzed using ANOVA and the Tukey HSD test. FUM1 gene was detected in 60% of the Fusarium spp. analyzed. The distribution of the gene within the isolates across the three regions was as follows: Narok: 54%, Uasin Gishu: 25%, and Nakuru: 21%. Tri13DON gene was not detected in the assessed potential deoxynivalenol (DON) producers. Fumonisin levels in the wheat samples from the three counties were significantly different (p

Technological advances in baking have enabled the use of bread as a food vehicle for various nutrients through use of composite flours. Orange-fleshed sweetpotato (OFSP) puree subjected to cold chain storage has been used to enrich bread with beta-carotene. However, this has proven expensive and inconsistent in supply of puree. This study sought to develop shelf-storable OFSP puree bread with similar sensory qualities to fresh OFSP puree bread. Bread in which two treatments of shelf-storable OFSP puree (treatments 1 and 2 with 0.5% potassium sorbate+0.5% sodium benzoate+1% citric acid and 0.2% potassium sorbate+0.2% sodium benzoate+1%citric acid respectively) were incorporated at 30% and 40% and were subjected to descriptive sensory analysis with white and fresh puree breads as controls. The results indicate that both the 40% and 30% wheat substitution with either treatment 1 or 2 OFSP puree bread are acceptable to the consumers, p

Wheat is a source of nutrients for around 40% world’s population and the second most important cereal crop in Kenya. However, Fusarium head blight (FHB) hinders sustainable sufficient production of the crop, causing both economic and health losses. With the emerging unfavorable climatic changes, effective disease management strategies and adequate seed system are necessary to meet the deficiency. Current information on prevalence of the causative pathogens in varieties of wheat genotypes is a critical prerequisite to such strategies. This study aimed at determining the prevalence of pathogenic Fusarium species in seeds of developed varieties of wheat genotypes in three major wheat-producing regions in Kenya. A total of 260 samples of 18 wheat genotypes from 123 farms were collected. Peptone pentachloronitrobenze agar was used for fungal isolation, while identification of Fusarium spp. was based on the gene encoding translation elongation factor 1-α (tef1-alpha) sequence analysis. Fusarium spp. isolated include Fusarium poae, F. tricinctum, F. heterosporum, F. culmorum, F. equiseti, Fusarium sp., F. verticillioides, and F. oxysporum. There was no significant difference in prevalence of Fusarium spp. pathogens among the three regions studied. Fusarium spp. diversity index for Nakuru was 2.008, Narok was 1.4603, and Uasin Gishu was 1.2337. Wheat produce from farm-saved seeds yielded 66.25% of the isolates, while the produce from certified commercial wheat seeds yielded 33.75% of the isolates. The significant finding of the study is that Fusarium spp. associated with mycotoxins that contaminate the wheat food chain seem to be flourishing in all the sampled wheat seed genotypes from the regions studied. Information on the prevalence and diversity of the pathogens on persistence of the disease in the crop is critical in advancing integrative FHB control measures.

In this study, the possibility of sexual reproduction in sampled Aspergillus flavus strains was evaluated by assessing the distribution of mating type (MAT) genes, which are known to control sexual character among fungi, for two counties in Kenya. Forty-four isolates from Nandi and Makueni counties were genotyped by MAT using a multiplex polymerase chain reaction assay. The primer pair for the MAT1-1 amplified a 396 base pair (bp) fragment containing an α-box motif, and MAT1-2 primers targeted a 270 bp segment with a high mobility group protein. The MAT1-2 genes dominated in both regions although the frequency was higher in Nandi (75%) than in Makueni (54.17%). There were no MAT1-1 genes sampled in Nandi, and in Makueni their proportion was 15.91%. The percentage of isolates that amplified for both MAT genes in Makueni was 9.09%, while in Nandi it was 11.36%. Currently, use of aggressive aflatoxin non-producing A. flavus strains as biocontrol is the most promising preharvest aflatoxin control strategy in Kenya. However, we address the possibility of introduced biocontrol strains to breed with existing aflatoxin producing strains in nature, which could lead to the generation of A. flavus offspring capable of aflatoxin production while also being aggressive colonizers and possibly increasing the burden of aflatoxin exposure in food.

Soil samples were collected from 8 land use types in Embu to study the effects of land use on soil chemical and physical parameters and on the occurrence of Trichoderma spp. The fungus was recovered from the soil using the dilution plate and soil washing technique. The remaining soil samples were used to measure the following characters of the soil; pH was determined in 1:1 (w/v) soil – water suspension with pH meter, total nitrogen was determined by the Kjeldahl method, available nutrients P, K, Na, Ca and Mg were determined using Mehlich method while total organic carbon was determined by calorimetric method. Land use type (LUT), plant cover, and soil physical and chemical properties influenced Trichoderma occurrence. The frequency of isolation of Trichoderma spp. was highest in napier LUT followed by indigenous forests. Carbon, N, Mg and Fe loaded with forest land use type suggesting their influence on fungal diversity in this LUT. The forests had clay loam soils with higher porosity and water retention capacity compared with the cultivated LUTs which were characterized with clay soils and bulk density. Napier together with other cultivated LUTs which had low records of the fungus loaded positively with Mn and Cu. This implied that plant type was the major determining factor for the high population of Trichoderma recorded in napier LUT. The diversity of soil factors observed in the fallow lands explained the influence of land management on soil physical and chemical characteristics which in turn determined the fungal distribution. Soil depth (0-20cm) did not influence soil factors though fungal diversity, abundance and evenness varied with depth suggesting the influence of other drivers.This study explains the fact that many factors interact in determining the occurrence of Trichoderma spp. and that in some situations it is the soil that is the key factor determining fungal occurrence and diversity while in others it is the plant type.

The distribution of Trichoderma species in soils of Embu and Taita regions in Kenya with relation to land use practices was investigated. The study areas were chosen because of their significant land use intensification and for being biodiversity hot spots. Soil washing and dilution plate techniques were used to recover Trichoderma spp from the soil samples collected from different land use types. The fungal isolates were identified and assigned to nine species from Embu soils and eleven species from the Taita soils. Greater populations were however observed in Embu than in Taita. Geographic differences between the regions mostly explain the differences in ecological niches of the two regions that result to different soil assemblages and plant types in the regions and therefore variation in available substrate for the fungus. Land use at each site affected the distribution, richness and abundance of Trichoderma with Napier grass having the highest abundance in both Embu and Taita while coffee had the lowest richness and abundance. Trichoderma favoured plants with shallow and widely spreading rooting systems, compared to the deeply rooted perennial coffee and tea trees. This underpins the importance of plant type and in effect land use system in the abundance of Trichoderma. The unevenness in the distribution of Trichoderma within the LUTs suggests yet another factor influencing the distribution of Trichoderma apart from the LUTs. Unevenness was greater in Embu than in Taita. The differences could mostly be attributed to soil management practices employed by different farmers while managing their land and crops differently. Trichoderma harziunum was the most frequently isolated species and the most abundant in both Embu and Taita. The presence of Trichoderma species in some land use types and the absence in others, provides a clue on the most preferred habitats, plants and/or crops. Considering the beneficial aspects of Trichoderma such as being antagonistic to the pathogenic fungi, crops or plants such as napier grass that induce high abundance and richness of Trichoderma can be used in crop rotations or in combinations with other crops to maintain high levels of the fungus in the soil.

An indigenous strain of Trichoderma spp. was tested for its ability to promote seed germination and growth of maize and bean seedlings grown in the field at Embu District, Kenya. The trial aws carried out for three seasons with the following treatments; two types of fertilizers, cow manure, and Trichoderma seed coat. Seedlings were counted 14 days after emergence from soil and a sample gently uprooted using a spade. Shoot height, root length, stem and root diameter measurements were taken. Trichoderma inoculation significantly increased rate of maize seed germination but had no effect on emergence of bean seedlings. Maize seeds coated with Trichoderma inoculum and planted on soils without fertilizer addition recorded the highest germination rate of 82.7% followed by seeds coated with the inoculum and planted in soils treated with manure (82.2%). Combination of the inoculum and fertilizer performed better at improving maize seed germination compared with fertilizers applied singly. This was the case for shoot and root growth. Seeds coated with the inoculum and planted in soils ammended with Triple Superphosphate and Calcium Ammonium Nitrate recorded the greatest shoot and root growth in both maize and beans. Increased growth of shoot and root caused by Trichoderma implied that there was beneficial effect of inoculation on plant growth and development since root collar and stem diameters were a measure of survivability of seedlings.

Fusarium root rot of maize and beans is a common problem in Taita District, Kenya causing reduction in yields to the small scale farmers. The pathogen attacks maize and beans at all growth stages causing rot at the seedling stage, yellowing of the leaves, stunted growth, and death if severe. Potentially effective crop rotations to maintain the pathogen at low levels are not currently practical due to the small size of farms while fungicides are out of reach to the small scale farmer due to high prices. This study aimed at assessing alternatives to fungicides in controlling root infection by Fusarium sp. in maize and beans. Field trials were done in Taita District where agriculture contributes to 95% of household income with very little or no soil fertility ameliorating inputs in farms. The following were tested in the trials; three types of inorganic fertilizers, cow manure, and Trichoderma seed coating. Planting was done during the long and short rains. Soil and roots were collected from the rhizosphere during harvesting and assessed for inoculum density while the roots were evaluated for incidence of infection by Fusarium spp. The most common species in both soil and roots were F. oxysporum (Schlecht) Snyd.et Hans. and F. sporotrichoides Sherb. Addition of soil ammandments had a positive effect of reducing root infection and in some cases lowering inoculum density in the soil. Of the four integrated soil fertility interventions, Mavuno had the highest yield and was the most effective in suppressing root colonisation by Fusarium spp.

Trichoderma has been widely studied for their biocontrol ability, but their use as biocontrol agents in agriculture is limited due to the unpredictable efficiency which is affected by biotic and abiotic factors in soil. Isolates of Trichoderma from Embu soils were evaluated for their ability to control Fusarium oxysporum f. sp. phaseoli., in vitro and promote seedling growth in the greenhouse. Bioassays were run using dual cultures and diffusible compound production analysis. The Trichoderma isolates significantly (p

Natural entomopathogenic nematodes (EPNs) are considered as potential biological control agents against soil-borne insect pests. This study was conducted to determine the impact of land use on the distribution, occurrence and diversity of entomopathogenic nematode community. Isolation of EPNs was done using the baiting technique and application of morphological identification methods revealed presence of the genus Steinernema. Land use intensification negatively affected the occurrence and recovery frequency in soils of Embu and Taita districts. The occurrence of EPNs was high in soils from coffee than maize and beans which had more nematodes than planted forest and napier grass followed by natural forest and tea respectively. PCR-RFLP of the internal transcribed spacer region on the ribosomal(r) DNA of the EPN isolates and digestion of the products by Alu I enzyme showed molecular variations among the isolates. The study has demonstrated that the frequency of occurrence and species variation of EPNs is different in various land uses.

Species in the genus Trichoderma are important as commercial source of several enzymes, biofungicides, and growth promoters. The most common biological control agents of the genus are strains of T. harzianum, T .viride and T. viriens. In this study, sixteen selected isolates of T. harzianum from different land use types in Embu, Kenya were tested for anatogonistic action against five soil borne phytopathogenic fungi (Rhizoctonia solani, Pythium sp, Fusarium graminearum, F. oxysporum f. sp phaseoli and F. oxysporum f. sp Lycopersici) using dual culture assay and through production of non-volatile inhibitors. Seven isolates were further characterized using RAPD-PCR procedure to determine genetic variability. All T. harzianum isolates had considerable antagonistic effect on mycelial growth of the pathogens in dual cultures compared to the controls. Maximum inhibition occurred in Pythium sp-055E interaction (73%).The culture filtrates obtained from Czapek’s liquid medium reduced the dry weight (mg) of the mycelia significantly while those from the potato dextrose broth showed minimum inhibition growth. Pythium sp was inhibited the most compared to other pathogens. Genetic similarities generated using Jaccard’s coefficient of similarity ranged from 0.231 between isolates 055E and 011E to 0.857 between isolates 010E and 015E. The technique of RAPD was efficient in demonstrating the DNA polymorphism in the isolates of T. harzianum tested showing intraspecific genetic variability. Since all T. harzianum isolates evaluated were effective in controlling colony growth of the soil borne pathogens both in dual cultures and in culture filtrates they should be tried as a broad spectrum biological control agent in the greenhouse and under field conditions.

The effect of soil fertility management practices on nematode destroying fungi was investigated for three seasons in Taita, Kenya. The study aimed at identifying soil fertility practice that promoted nematode destroying fungi in the soil. Field experiments were established in Taita district, the treatments comprised of Mavuno fertilizer, Triple super- phosphate and calcium ammonium nitrate (TSP+CAN), cow manure and a control where no amendments were applied. This experiment was replicated in ten farms and repeated in three planting seasons. Isolation of nematode destroying fungi carried out was using the soil sprinkle technique and the isolates were identified using the key described by Cooke and Godfrey (1964). There were significant difference (P= 1.705 x 10-06) in occurrence of the nematode destroying fungi between soil fertility treatments. The highest mean (1.6) occurrence of nematode destroying fungi was recorded in soils amended with cow manure and the least (0.7) was recorded in soils from the control plots. A mean of 0.78 was recorded in soils from both TSP+CAN and Mavuno fertilizers. Plots amended with cow manure presented the highest diversity of nematodes followed by the control, then TSP+CAN and least in Mavuno with shannon indices of 0.34, 0.15, 0.13 and 0.11 respectively. Sixty percent of all the isolated nematode destroying fungi genera were from plots treated with cow manure and only twenty percent were from plots amended with the inorganic fertilizer. The control plots recorded higher number of nematode destroying fungi compared to the soils that received inorganic fertilizers.

A green-house study was conducted to investigate the ability of an isolate of Trichoderma harzianum (P52) and arbuscular mycorrhizal fungi (AMF) in enhancing growth in tomato seedlings, tea and napier grass cuttings. The effect of these bio-inoculants on growth was compared with the influence of Diammonium phosphate (DAP) fertilizer and the interactions of these three factors (P52, AMF and DAP). The plants were grown in plastic pots filled with sterilized soils. A completely randomized design was used and growth measurements taken on height shoot and root dry weights. Â It was observed that isolate P52 and DAP fertilizer individually enhanced growth in tomatoes, tea and napier while AMF only enhanced growth in tomatoes. Combinations of P52 and DAP; P52, AMF and DAP enhanced growth significantly (P

Agricultural intensification has been cited as one of the causes of loss of biodiversity. Taita Taveta, a coastal highland region is such like area which has experienced land conversion from forest cover into farmlands with high soil intensification. Soil samples were collected across seven land use types and analysed for Trichoderma occurrence. The fungus was recovered from the soil using the dilution plate and soil washing technique. The remaining soil samples were used to analyse for pH, acidity, organic carbon (C) total nitrogen (N), organic matter (OM), calcium (Ca) phosphorus (P) sodium (Na), potassium (K), magnesium (Mg), Manganese (Mn), Iron (Fe), and Zinc (Zn), and copper (Cu). Soil texture, bulk density, porosity and available water capacity was also determined. Land use type (LUT), plant cover, and soil physical and chemical properties influenced Trichoderma occurrence. The frequency of isolation of Trichoderma spp. was highest in indigenous forests followed by fallow and horticulture LUTs. Maize and Coffee LUTs recorded the least. The most frequently occurring species was T. harziunum which was isolated from all land use types LUTs. Carbon, N, organic matter and Fe were high in soils collected from forests thus suggesting they influenced fungal diversity. The forests had clay loam soils with higher porosity and water retention capacity compared with the cultivated LUTs and fallow which were characterized with clay soils and high bulk density, pH, Na, P, K, Ca, Mg, Cu showing the effect of land conversion on soil properties and Trichoderma occurrence. The influence of plant type and land management is also seen in the cultivated LUTs with the same soil properties but with different diversity and abundance of Trichoderma. The diversity of soil factors observed in the maize plots explained the influence of land management on soil physical and chemical characteristics which in turn determined the fungal distribution. Soil depth (0-20cm) did not influence soil factors though fungal diversity, abundance and evenness varied with depth suggesting the influence of substrate availability. Occurrence of Trichoderma spp. and distribution in soil is determined by a number of interacting biotic and abiotic factors

Genetic relatedness among twenty six Fusarium species isolated from soils in six different Land Use Types (LUTs) across a land use gradient was evaluated using Random Amplified Polymorphic DNA (RAPD) assay. The six LUTs were horticulture, maize, napier grass, fallow/shrub land, planted forests as well as indigenous forests. Six primers were used in this assay. Amplification products were examined and presence or absence of each size class of bands was scored as 1 and 0, respectively. The resulting matrix was used to compute Jaccard’s similarity coefficients and Unweighted Pair Group Method with Arthmetic mean (UPGMA) cluster analysis using computer package NTSYS-pc. Jaccard’s similarity coefficients ranged from 0.257 to 0.583 among the Fusarium species studied indicating high genetic diversity. The UPGMA cluster analysis grouped the 26 Fusarium species into two main clusters with the first cluster comprising of 17 species with genetic similarity values ranging from 26.2 to 58.3 %. The second cluster comprised of 9 species with genetic similarity values ranging from 29.5 to 56.34 %. Fusarium avenaceum and F. nygamai depicted the highest genetic similarity of 58.3 %.

The distribution of Pythium species across land use gradient was examined in two agroecological zones in Kenya. The two zones were selected owing to their unique characteristics and locations. Soil samples were collected along a transect from the forest through to the cultivated land. The sample plots were established at fixed intervals of a distance of 200m apart to avoid auto-correlation Pythium propagules were activated to germination using baiting techniques, and the mycelium baited was cultured to obtain axenic culture for identification. Based on morphological characteristics, a total of 32 species of Pythium were found at the Embu study site, with soil under Napier having the most diverse population and that under maize the least. The Taita site yielded 12 Pythium species, with the highest diversity in cropped plots and the lowest in Natural forest. Species abundance increased with increasing ecosystem disturbance while diversity increased with decrease in disturbance. All the species isolated from the Taita site were also sampled from the Embu site except P. helicoids, P. periplocum and P. grandisporangium. The common pathogenic species P periplocum, P. hypogynum and P. spinosum were isolated mostly from croplands confirming the effect of host occurrence on the distribution of Pythium species.

The effect of Land Use Types (LUTs) on distribution and diversity of soil Fusarium species was carried out in Taita Taveta district, Kenya. Soil samples were collected from sixty sampling points across a land use gradient covering six different LUTs, at the depths of 0 to 10 and 10 to 20 cm. Using Fusarium-selective media, a total of 1865 Fusarium isolates were recovered from the soil samples which resulted into 26 Fusarium species. Fusarium oxysporum and Fusarium solani were the dominant species in this area. Difference in Fusarium abundance, diversity and richness across the LUTs was significant (P

In Kenya, the below-ground biodiversity (BGBD) project selected two benchmark sites for the inventory of soil biota; these included the Irangi and Ngangao forest sites in the Mount Kenya region of Embu District and the Taita Hills area of Taita Taveta District. The areas selected by the project were located in biodiversity hotspots that are supporting rare and endemic plant and animal species. For more in-depth studies and analysis, the broader Embu and Taita benchmark areas were further sub-sampled into smaller areas that we refer to as study areas, designated by the symbols E1 and E2 for Embu and T1 and T2 for Taita benchmark. Within the study areas, we plotted and sampled 200x200 square grids for collecting soil as well as socio-economic data. Site characterization was carried out using the method provided by FAO-UNESCO for characterizing and classifying soils. Further to this, attempts were made to establish land use intensity (LUI) and land productivity (PI) indices that provided land condition indicators. The indicators offered insights into the quantitative relationship between the environmental conditions and land use. Parameters used in the computation of the land use intensity were; total quantity of inputs per ha, the frequency of input application, cropping intensity and cultivation frequency. The soils in Taita Taveta benchmark site were classified as Plinthic Lixisols, Plinthic Acrisols, Dystric Cambisols and Chromic Luvisols, while those from Embu ones were Rhodic Nitisols, Humic Nitisols, Humic Acrisols, Haplic Acrisols and Umbric Andosols. The highest level of soil organic carbon recorded was 7.6% in the forest and the lowest value of 1.6% in intensely cultivated maize-based and horticultural systems. Low land use intensity gradients were observed in the forests (LUI40%). The productivity index (PI) followed a similar trend, being highest in the natural forest and grassland (40-50%) and lowest in horticultural and maize-based systems (15-20%) It was concluded that the decline in soil quality and productivity was linked to increased land use intensification and lack of knowledge of the appropriate management practices for sustainable ecosystem functions and services.

A survey was carried out to establish the effects of Land Use Types (LUTs) on Arbuscular Mycorrhiza Fungi (AMF). AMF spore abundance and colonization were evaluated. The percentage root colonization was assessed in trap plants only. AMF were identified and enumerated from spores extracted directly from field soils. Soils were sampled from 60 points occurring in central Kenya. A total of 17 AMF species were isolated and 14 identified to species level. The spore community was dominated by Acaulosporaceae, and Glomaceae. Land use type had no significant (p

This study was undertaken to determine whether nematode destroying fungi can be used as indicators of soil disturbances. Soil samples were collected from an indigenous forest, maize/bean, napier grass, shrub and vegetable fields, which represented the main land use types in Taita Taveta district of Kenya. The fungal isolates obtained were grouped into seven genera. The species identified were, Acrostalagums obovatus, Arthrobotrys dactyloides, Arthrobotrys oligospora, Arthrobotrys superba, Dactyllela lobata, Haptoglosa heterospora, Harposporium anguillulae, Harposporium.sp, Monacrosporium cionopagum and Nematoctonous georgenious. Occurrence of nematode destroying fungi was significantly (P = 3.81 x 10 -7) different among the land use systems in the study area. Out of the isolates that were positively identified, 33.7 %, 27.9 %, 20.9 %, 11.6 % and 5.8 % were from fields under vegetable, maize/bean, napier grass, shrub and forest, respectively. Soil disturbance accounted for the highest occurrence of nematode destroying fungi (60.77 %) of the two main factors in the principal component analysis. While moisture, the second factor accounted for 23.35%. Fungal isolates from vegetable gardens were most diverse but the least even while the forest land use was most even but least diverse. The total richness of nematode destroying fungi was nine, in vegetable and maize/bean fields while was seven, six, and three in napier, shrub and forest habitats respectively in their decreasing order of disturbance. This study has established that nematode destroying fungi increases with increased land disturbance.

The reasons for the lack of inclusion of below-ground biodiversity in the Kenyan policy and legal framework were sought. Gaps were identified in the relevant sectoral policies and laws in regard to the domestication of the Convention on Biological Diversity (CBD). Below -ground biodiversity had no specific schedule in any of the sectoral laws. Most sectoral laws were particular about the larger biodiversity and soils but had no mention of below-ground biodiversity. Material Transfer Agreements and Material Acquisition Agreements that are regarded as tools of domestication of the CBD to guide transfers, exchanges and acquisition of soil organisms lacked a regulating policy. The lack of regulating policy could be attributed to the delay in approval of draft regulations by the Ministry of Environment while the lack of inclusion of below-ground biodiversity in Kenya’s legal and policy framework could be as a result of lack of awareness and appreciation among stakeholders.

Due to the increased concerns about the effect of agro-chemicals on soil health and soil biodiversity, use of biological methods has become most acceptable alternative methods for farmers to control soil pathogens during crop production. A study was therefore undertaken to determine the occurrence of nematode destroying fungi in Taita Taveta with the aim of isolating and characterizing them for biological control of plant parasitic nematodes. Twenty eight fungal isolates, distributed in three genera, were identified as nematode destroying fungi from all the positive soil samples. Out of the isolates that were identified, 71, 25 and 4 % were in the genera Arthrobotrys, Monacrosporium and Nematoctonus respectively. Arthrobotrys oligospora had an occurrence frequency of 42.9% which was the highest followed by A. dactyloides, M.cionopagum, Monacrosporium sp and Nematoctonus sp with frequencies of 28.6, 17.9 and 7.1and 3.6% respectively. The occurrence of nematode destroying fungi was affected by land use and organic inputs (P ≤ 0.05) while it was not affected by crop rotation (P ≥ 0.05). Napier land use was more diverse than the other land uses with a mean shannon diversity index of 0.717 followed by horticulture (index 0.497). Maize /bean, coffee/beans, fallow and shrub land uses had a mean shannon index of 0. The same trend was observed on richness where napier had a mean richness of 2.2, horticulture 1.8, maize bean 1 while shrub, fallow and coffee/ beans all had mean richness of 0.2. A.oligospora was the most frequently isolated fungi (42.9 %) and showed high potential in biocontrol of plant-parasitic nematodes and was recommended for further studies and development as a biological control agent.

Arbuscular Mycorrhizal Fungi (AMF) are important in agriculture and have received attention as they are considered a part of an active and diverse soil biological community essential for increasing the sustainability of agricultural systems. However, most of agricultural practices have a negative impact on AMF association and agricultural soils are AMF impoverished. Interventions to replenish AMF include re-introduction through inoculation or manipulation of existing AMF to increase density. A major problem with inoculation is that there is possible competition with native (indigenous) AMF species. Indigenous AMF will be more adapted to the soil environment than introduced strains but with conflicting results on the effects of AMF inoculation on crop yield, more field studies for different ecological areas are required. The objective of the study was to compare the effect of inoculating crops with indigenous AMF applied applied singly or combined with other Soil Fertility Amendment Practices (SFAP) on root colonisation and subsequent performance of maize (Zea mays L.) and common bean (Phaseolus vulgaris L.). Analysis was also done on the best soil amendment practice that encourages crop colonisation by AMF. This was tested under field experiment and compared with control treatment (no soil amendment practice) and three other soil fertility amendment practices used singly or in combination with AMF; (1) MAVUNO (macro- and micronutrients and secondary nutrients) fertilizer, and (2) Calcium Ammonium Nitrate (CAN) and Triple Super Phosphate (TSP) (3) cattle manure. Maize and bean performances were determined and compared between the treatments for a period of two consecutive seasons with the experiment replicated in two benchmark sites of Embu district (highlands of central Kenya) and Taita-Taveta district (coastal highlands). Soils at Embu have high soil pH than at Taita which results in low phosphorus levels and possible micronutrients deficiencies. Even though no significant differences were observed from root colonisation by AMF with application of SFAP, significant differences were observed at the crop yield. Bean crop was more responsive to AMF inoculation than maize in terms of yield. Combination of AMF inoculant with other organic and inorganic fertilizers resulted in higher crop yield compared to AMF applied singly. Thus, utilisation of indigenous AMF species has potential to constitute an environmentally friendly method of soil fertility amendment over time to improve maize and bean production potential of small-scale holders but consideration should be done on the local soil nutrients conditions, other soil fertility amendment practices in use and the targeted crop.