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The National Research Fund facilitates research for the advancement of Science, Technology and Innovation. One of our core functions is to compile and maintain a national database of research and innovation projects funded by the Fund and other agencies as per the STI Act of 2013.
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Recent Submissions
Preferential Use of Sahiwal Bull Calves by Beneficiaries of Assisted Reproductive Technologies in Southern Rangelands of Kenya
(European Journal of Agriculture and Food Sciences, 2023-06-28) Fredrick O. Agutu, Samuel M. Mbuku, James O. Ondiek, and Bockline O. Bebe
Bull service is the most common insemination method in pastoral herds
grazing in the rangelands. To accelerate multiplication and distribution of
and access to high quality Sahiwal genetics to pastoral communities,
development agencies have promoted the use of Assisted Reproductive
Technologies (ARTs) in the Kenyan rangelands. However, sustainable use of
ARTs is uncertain because pastoral herd owners attach high value to bull
calves of high genetic merits for breeding, which is a potential barrier to
technology adoption. This study assessed preferential use of ART- bull calves
among beneficiaries of the Sahiwal cattle upgrading breeding program that
were utilizing OvSynch and TAI protocol in the southern rangelands of
Kenya. Preferential use of bull calves was assessed in a choice experiment
basing on attributes associated with potential use of bull calves. Overall, the
first-choice preference was to retain the bull calves for future breeding
(54%) compared to immediate selling for income (44%). This was the firstchoice of pastoralists and agro pastoralists preferred unlike ranchers who
preferred selling bull calves for income compared to retaining for future
breeding (80% versus 20%). The preference of retaining bull calves for
future breeding was higher among women compared to male respondents
(59% versus 51%). Second choice preferences were sales for income (58%),
breeding (29%), draft power (5%), meat production and cultural practices
(3% each) and prestige (2%). Socioeconomic factors had no significant
influence on preferential use of ARTs bull calves. The results indicate that
high genetic merit bull calves are preferred for breeding, implying that bull
calves would be retained within the pastoral herds for bull service. This
presents a possible barrier to adoption of ARTs in pastoral herds for
upgrading of Sahiwal cattle breed. Policy direction need to invest in Sahiwal
multiplication and distribution of bull calves to pastoralists and agro
pastoralists. Ranchers have low preference for retaining bull calves for
breeding, so it would be best to capacitate them to invest in ARTs to multiply
breeding bulls and supply to pastoralists and agro pastoralists.
ANTI-DERMATOPHYTIC ACTIVITY OF Salvia nilotica METHANOLIC LEAF EXTRACT AGAINST Trichophyton mentagrophytes
(2021) JOSEPH KIPROP CHEPKWONY
Conventional medicine used against dermatophytosis has resulted in treatment failure,
relapses of the fungal infection and side effects due to its use. Herbalist in the Tugen
community in Kenya claim that Salvia nilotica leaves have anti-dermatophytic effects
however, there is no scientific documentation for these claims. This study therefore sought
to determine the phytochemical constituents in S. nilotica methanolic crude leaf extract and
its anti-dermatophytic activity against the dermatophyte, Trichophyton mentagrophytes and
probable mode of action through the effects on Metalloprotease 2 (MEP2), Sulphite efflux
pump (SSU1), Subtilisin 3 (SUB3) and dipeptidyl-peptidases V (DDPV) target genes. The
phytochemical constituents of methanolic crude leaf extract of S. nilotica were determined
using standard methods. Food- poisoned technique was used to determine antidermatophytic activity of S. nilotica extract at different concentrations ranging from 7.76
mg/mL to 77.59 mg/mL. Plausible mode of action was determined using quantitative real
time polymerase chain reaction to establish the effect of S. nilotica methanolic leaf extract
treatment on MEP2, SSU1, SUB3 and DDPV genes of Trichophyton mentagrophytes
versus the standard drug fluconazole. Qualitative phytochemical analysis of the methanolic
crude leaf extracts of S. nilotica indicated the presence of tannins, saponins, flavonoids,
terpenoids, steroids, alkaloids, carbohydrates, amino acids and glycosides but there was
absence of phlobatannins and anthraquinones. This study also found that S. nilotica crude
leaf extract has anti-dermatophytic activity against Trichophyton mentagrophytes. The
activity of crude leaf extract of S. nilotica on Trichophyton mentagrophytes was not
significantly different (p < 0.05) when compared with fluconazole. In addition, all the
Trichophyton mentagrophytes genes, which were targeted in this study, were down
regulated by different folds depending on the concentration of the antifungal agent used.
The down regulation noted was -1.7, -1.9, -1.1 and -1.1 folds for MEP2, SSU1, SUB3, and
DPPV genes respectively at 0.30 mg/mL of fluconazole. At 0.50 mg/mL of fluconazole,
the genes were down regulated by -4.2, -2.9, -1.6 and -34.4 folds for MEP2, SSU1, SUB3
and DPPV respectively. S. nilotica at 13.97 mg/mL down regulated the target genes by -1,
-1.2, -1.2 and -38.4 folds for MEP2, SSU1, SUB3, and DPPV genes respectively. Similarly
at the concentration of 77.59 mg/mL of S. nilotica the genes were down regulated by -1.3, -
7.9, -2.3 and -2211.8 folds for MEP2, SSU1, SUB3 and DPPV respectively. In conclusion,
this study has shown that S. nilotica crude leaf methanolic extract could offer a potential
alternative medicine for dermatophytosis treatment.
PHYSICAL AND CHEMICAL CHARACTERIZATION OF FRESHLY HARVESTED AND FACTORY-PROCESSED MANGROVE HONEY FROM KILIFI COUNTY, KENYA
(2021-11) OMORI NANCY KWAMBOKA
Mangrove honey from the mangrove forests at the Kenyan coastal region has been
in production at the commercial level by beekeepers organized and registered in
self-help groups for more than a decade now. The honey is said to have medicinal
properties but it has not been fully characterized to determine whether it meets the
Kenyan standards on Honey – Specification (KS EAS 36:2020), European Union
(EU) Directive on Honey (2001/110/EC) and International Honey Commission
(2009). The objective of this study was, therefore, to characterize Kenyan
mangrove honey in terms of its physicochemical properties and volatile organic
compounds present. It was also important to correlate the honey VOC profiles
with the mangrove tree flowers extract profiles. Unprocessed honey sampling was
done from selected beekeepers from the four mangrove forest regions of Kilifi
County, namely, Mida, Kilifi, Watamu and Mtwapa creeks while processed honey
samples were obtained from Kwetu Training Centre. Twenty (20) honey samples
weighing approximately 250 g each were collected randomly from farmers and
factory in different locations in Kilifi County, packed in 500 cm3 plastic bottles,
ferried for refrigeration in the lab at a temperature of 4o C. Mangrove flower
volatile organic compounds (VOCs) were collected by static headspace solid
phase microextraction (HS-SPME) fiber while collection of VOCs in honey
samples was done by ultrasound-assisted solvent extraction (USE) method.
Mangrove honey was analyzed for moisture content (by refractometry), colour
index, diastase, proline and hydroxymethylfurfural (by spectrophotometry), pH
and electrical conductivity (by pH/conductivity meters), free acidity (by
titrimetry), sugar content (high performance liquid chromatography) and volatile
organic compounds (by GC-MS). Quantitative data was analyzed using the SPSS
program version 21. The results showed that the mean moisture content ranged
from 23.40±0.00 to 19.23±0.06%, mean pH from 4.45±0.05 to 4.00±0.00, mean
electrical conductivity ranged from 0.54±0.00 to 0.32±0.00 MS/cm. The mean
acidity ranged from 30.21±0.15 to 22.20±0.00 Meq/kg. The mean proline content
ranged from 734.36±4.23 to 602.24±2.68 mg/kg. The mean HMF levels were in
the range of 2.86±0.14 to 0 mg/kg. The mean invertase content ranged from
9.55±0.10 to 5.54±0.11 U/kg. The mean diastase content ranged from
11.48.47±0.06 to 8.11±0.64 S/units. In the VOCs profile of mangrove flower,
factory and farm, 119, 90 and 70compounds were identified, respectively. Of the
identified VOCs, 35 were found both in the honeys analyzed and in mangrove
flower. Three compounds docosanoic acid, palmitoleic acid and n-hexadecanoic
were found in large quantities in all samples analyzed and the mangrove flowers
and can be considered to be chemical markers for mangrove honey. The HMF,
diastase and invertase were found to be below the set limits suggesting that the
mangrove honey studied was fresh and had not been heated by farmers during
harvesting and extraction. The high proline content also revealed that nectar and
pollen are produced in great quantities by mangrove plants. The rest of the
physicochemical parameters were found to be within the limits set by the
International Honey Commission, Codex Alimentarius and the Kenya bureau of
standards (through the EAS)
DEBT MANAGEMENT PRACTICES AND LOAN PERFORMANCE OF COMMERCIAL BANKS IN KENYA
(2021-10) MERCY AKINYI OWICH
This analysis examined debt management practices and performance of loan of the commercial
banks in Kenya. The analysis anchored on the fact that loan performance linked to economic
performance. Economies tend to be unstable especially in financial crises when non-performing
loans increase. For instance, the non-performing loan rates after applying the debt management
techniques entails 5.46%, 5.99%, 8.59%, 9.95%, and 11.69% for 2015-2019 respectively. The key
objective of the study was to evaluate the effect of debt management practices on loan performance
of commercial banks in Kenya. The specific objectives of the study included, establishing the
effect of credit risk assessment on loan performance of commercial banks, to determine the effect
of periodic loan review on loan performance of commercial banks in Kenya, to evaluate the effect
of loan collateral on loan performance of commercial banks in Kenya, and to determine the effect
of early warning signs of loan delinquency on loan performance of commercial banks in Kenya.
Most reviews have examined credit performance, commercial banks performance and many more
but there has not been much research on debt management practices and loan performance of
commercial banks in Kenya. The period scope of the study was 2015-2019. The research anchored
on debt management, information asymmetry and moral hazard theories. The research design
applied was causal research design. The target population of the research project was 108 managers
from banks in tier II and tier III. The research embraced purposive sampling to come up with a
sample size of 85 respondents. The data was collected using questionnaires. The data collected
from the questionnaire was analyzed using IBM SPSS version 21.0 software. The findings were
then classified, tabulated and summarized using figures. Therefore, the analysis identified that
commercial banks loan performance aligns with the effectiveness of credit management practices
evident in the banks. The credit management practices that entail character, capacity, capital,
conditions, and collateral were less effective to loan performance than third party security. Periodic
loan review tends to be effective in loan performance as determined in the study with a positive
significance level as well as the extent of loan collateral presence on loan performance. The
analysis recommended that the commercial banks and the government to evaluate and formulate
policies that regulate exercises on credit risk management of loan delinquency
PHENOTYPIC, PHYSIOLOGICAL CHARACTERS AND QUANTITATIVE TRAIT LOCI IN F2 GENERATION OF Phaseolus vulgaris UNDER DROUGHT STRESS IN MACHAKOS COUNTY, KENYA
(2022-01) CHARLES KIPKOECH LANGAT (MSc.)
Currently, yield of common bean (Phaseolus vulgaris L.) in smallholder systems in Kenya
is comparatively low; standing at 400 kg ha-1
against global average of 960 kg ha-1
. The low
yield is attributed to drought which has become a major constraint affecting more than 60%
of common bean production across the world. The most effective measure to mitigate
effects of drought on common bean production is development of drought tolerant
genotypes. Hence, there is need to select for drought tolerant genotypes from the local
germplasm of common bean for hybridization. The current conventional method used in
screening for drought tolerant bean genotypes involve long duration of field testing.
Therefore, there is need to use other alternative method like, marker assisted selection
(MAS) using DNA markers linked to quantitative trait loci (QTL) that could quicken the
selection process and subsequent development of drought tolerant genotypes. The objectives
were to; i) assess phenotypic and physiological characters associated with drought tolerance,
ii) characterize F2 (KAT B1 × GLP2) population for drought tolerance using phenotypic
and physiological characters, iii) determine QTLs associated with drought tolerance in an F2
(KAT B1 × GLP2) population of common bean. A series of experiments were carried out to
elucidate the phenotypic and physiological characters and map quantitative trait loci (QTL)
for drought tolerance in common bean. Six genotypes; KAT B1, GLP2, Nyota, Angaza,
Faida and Metameta were assessed in a rain-out shelter under water stress for phenotypic
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and physiological characters related to drought tolerance. Characterization of phenotypic
and physiological characters was also carried out in F2 population consisting 116
individuals previously developed from KAT B1 × GLP2 cross. The F2 population
comprising of 120 lines derived from KAT B1 and GLP2 were mapped for quantitative trait
loci (QTL) linked with drought tolerance. The experiments were laid out in a randomized
complete block design replicated three times. Stomatal conductance and stem biomass
showed greatest variation among genotypes and had significant positive correlations with
yield per plant under water stress. Estimates of expected genetic advance indicated that high
gains and progress are attainable on genotypic selection for characters such as days to
maturity, pod number plant-1
, stomatal conductance and leaf water potential at 34.97 %,
22.32 %, 22.87 % and 25.46 % respectively. High estimate values for heritability in broad
sense were also obtained for these characters. A genetic linkage map with a total length
spanning 634 cM of the common bean genome at an average distance of 2.02 cM between
adjacent markers was generated using 229 single nucleotide polymorphism (SNP) markers.
A total of twenty three QTLs were detected for the branch numbers, pod numbers, grain
number per pod, stem biomass, leaf biomass, pod biomass, days to flowering and maturity,
100-seed weight, seed yield, stomatal conductance and leaf water potential. Two putative
QTLs involved in drought adaptation mechanisms were detected; SCO4.1KG associated with
stomatal conductance on chromosome Pv04 and LWP1.1KG associated with leaf water
potential chromosome Pv01. Overall, this research provided insight into the genomic
regions (QTLs) controlling traits related to drought tolerance in common bean. Given the
long duration taken in developing improved common bean cultivars using conventional
phenotypic selection, the identified QTLs should be incorporated in marker assisted
selection in screening and selection of high yielding and drought tolerant genotypes hence,
hastening common bean improvement efforts.
