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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
Assessing and Enhancing the Impact of Cotesia plutellae in Management of Diamondback Moth Plutella xylostella on Kale Brassica Oleracea var. acephala in Semi-Arid Areas of Kenya
(Journal of Environmental and Agricultural Sciences, 2017-06-30) R. Kahuthia-Gathu, M. Mwangi, M.O. Fiaboe
Diamondback moth (DBM, Plutella xylostella L.) is a major pest of crucifers
which can cause yield losses of up to 100% if left unmanaged. Classical biological control of
DBM was adopted in Machakos and Kitui County through Cotesia plutellae imported from
South Africa in 2002 and released in March 2004 in farmers’ fields where kale Brassica
Oleracea var. acephala is one of the major leafy vegetables. Preliminary studies in 2004-
2006 showed that the parasitoid had not established in the release sites and augmentation
releases were done in 2006. Monthly surveys were conducted (May 2012 to April 2013) to
assess the spread and contribution of C. plutellae in the management of the DBM. Brassica
oleracea var. acephala fields in twenty five randomly selected farms were sampled for
number of DBM larvae and pupae, damage, parasitism and parasitoid guild. The data was
recorded from 20 plants in each selected farm. The DBM larvae and pupae were placed in
plastic containers and taken to the laboratory for DBM or parasitoid emergence. Results
revealed that the mean number of DBM/plant in Kitui and Matuu ranged from 0.4 to 2.5 and
0.3 to 3.5, respectively. Mean damage score ranged from 1.2 to 1.6 in both regions, which
was positively correlated to the number of DBM on B. oleracea var. acephala.
Hymenopteran parasitoids recovered from DBM included Cotesia plutellae, Diadegma
semiclausum, D. mollipla, Apanteles sp., Chelonus sp., Oomyzus sokolowskii and Itoplectis
sp., while the hyper parasitoids included Mesochorus sp., Pteromalus sp., Notanisomorphella
sp., Eurytoma rosae and Eurytoma sp., Brachymeria sp. and Pediobius sp. Cotesia plutellae
was the most abundant parasitoid followed by D. semiclausum. Diversity of parasitoids
varied between months and study sites. Cotesia plutellae had established and spread beyond
the release sites contributing between 40 and 90% parasitism while the indigenous
parasitoids Itoplectis sp., Apanteles sp., and D. mollipla contributed less than 5% parasitism.
The results show the spread and establishment of C. plutellae in the study sites. In conclusion,
there is need for continuous training and educating the farmers to conserve the parasitoids
that have contributed in the reduction of the DBM and damage on the crop. This has
contributed in the reduction on pesticides use, spraying regime and eventual reduction of cost
of production and residues on the produce.
Next-Generation Antimalarial Drugs: Hybrid Molecules as a New Strategy in Drug Design
(2009 Wiley-Liss, Inc., 2010) Francis W. Muregi and Akira Ishih
Malaria is a disease that affects nearly 40% of the global population, and chemotherapy
remains the mainstay of its control strategy. The global malaria situation is increasingly being exacerbated
by the emergence of drug resistance to most of the available antimalarials, necessitating search for novel
drugs. A recent rational approach of antimalarial drug design characterized as ‘‘covalent bitherapy’’
involves linking two molecules with individual intrinsic activity into a single agent, thus packaging dualactivity into a single hybrid molecule. Current research in this field seems to endorse hybrid molecules as
the next-generation antimalarial drugs. If the selective toxicity of hybrid prodrugs can be demonstrated in
vivo with good bioavailability at the target site in the parasite, it would offer various advantages including
dosage compliance, minimized toxicity, ability to design better drug combinations, and cheaper
preclinical evaluation while achieving the ultimate object of delaying or circumventing the development
of resistance. This review is focused on several hybrid molecules that have been developed, with particular
emphasis on those deemed to have high potential for development for clinical use. Drug Dev Res
71:20–32, 2010.
EFFECTS OF LEGUME COVER CROPS ON SOIL PROPERTIES AND PRODUCTIVITY OF GRAFTED ORANGES (Citrus sinensis) IN THE COASTAL LOWLANDS OF KENYA
(2017-07) JACKSON MUEMA MULINGE
Orange (Citrus sinensis) is an important food and cash crop in coastal lowland of Kenya. The
average orange production in Kenya is 12 tones/ha Compared to world production of 16
tones/ha due to low soil fertility, diseases and high costs of inputs. There is, therefore, a need
to develop a sustainable and low input production system for increased orange productivity
and improved fruit quality in coastal lowland of Kenya. This study was tconducted at
KALRO-Matuga, Ganda and Vitengeni within the coastal region of Kenya from May 2012 to
April 2015. The effects of legume cover crops on soil moisture, orange feeder root
distribution, soil pH, plant nutrients, orange yield and fruit quality was evaluated. There were
four treatments; mucuna (Mucuna pruriens), cowpea (Vigna unguiculata), dolichos (Lablab
purpureus) cover crops and a fallow as the control. The experiment was laidout in a
randomized complete block design (RCBD) where the treatments were replicated four times
within four blocks in an existing grafted Valencia orange orchard. Soil and orange root
sampling was between 2m and 3m radius from the orange trees trunk at two depths topsoil
(0-20 cm) and sub-soil (20-40 cm). Fruit and leaf samples were taken from the orange trees.
Data collected was subjected to analysis of variance (ANOVA) at (P ≤ 0.05) using
procedures of R statistical analysis version 3.3.2. Mean separation was done using the least
significant difference (LSD) at (P ≤ 0.05) level of significance. Mucuna, dolichos and
cowpea increased soil moisture content in orange orchard for all the site topsoil while in the
sub-soil is only mucuna and dolichos increased moisture content in the soil. Mucuna and
dolichos increased orange root density in the top and sub-soils. Mucuna, cowpea and
dolichos increased soil nitrogen in the orange orchard top and sub-soil. Mucuna, cowpea and
dolichos increased soil organic carbon in the orange orchard top and sub-soil. Mucuna
increased phosphorous in the top and sub-soil of orange orchard. Dolichos increased
phosphorous in the topsoil of orange orchard.. Cowpea and dolichos increased phosphorous
in the sub-soil of orange orchard. Mucuna, dolichos and cowpea increased the potassium in
the topsoil of orange orchard while in the sub-soil, potassium increase due to mucuna and
cowpea. Mucuna dolichos and cowpea increased orange leaf chlorophyll content. The orange
fruit number increased due to mucuna and dolichos. Orange fruit weight increased due to
mucuna and dolichos. Fruits size increased due to mucuna and dolichos. Fruits juice
increased due to mucuna and dolichos. Orange fruit brix increased due to mucuna and
dolichos. In conclusion, mucuna, dolichos and cowpea are effective in improving soil
moisture, root distribution and nutrients in the soil and orange yield and fruit quality. The use
of mucuna however, had the highest increase and it is strongly recommended as a cover crop
in orange production. Further research is however recommended to evaluate the long term
(>3years) effect of the cover crops under different Agro-ecological zones.
MODERATING ROLE OF ENTREPRENEURIAL ORIENTATION ON THE RELATIONSHIP BETWEEN INFORMATION TECHNOLOGY COMPETENCE AND FIRM PERFORMANCE IN KENYA
(International Journal of Professional Business Review,, 2017-12-27) Stanley Ndungu, Kenneth Wanjau, Robert Gichira, Waweru Mwangi
This study explored moderating role of entrepreneurial orientation on the relationship between Information
Technology Competence and firm performance in Kenya. The impact of IT on FP remains debatable to-date
because some results of previous studies have had high variations resulting from diversities in the
conceptualization of the key constructs and their interrelationship, coupled with the exclusion of intangible effect
of IT on performance. In Kenya, SMEs employ about 85 percent of the workforce. The need to link ITC with FP has
become vital for firms striving to achieve superior performance. However, limited attention has been paid to the
link and more so to the moderating role of EO on ITC- FP relationship model. To better understand this
relationship, this paper adopted a mixed methods research guided by cross-sectional survey design. Quantitative
and qualitative techniques were employed to analyze the collected data using SPSS, Ms-Excel, AMOS, SmartPLS,
STATA, R-GUI and ATLAS.ti analytical softwares. Analyses were conducted using a two-phase process consisting of
CFA and SEM models. The theoretical models and hypotheses were tested based on empirical data gathered from
94 SMEs in the 2013 Top 100 Survey. The study found that ITC had a positive relationship with FP. The results also
revealed that EO did not significantly moderate the relationship between ITC and FP in Kenya. However, when run
with the interaction term, the Technical (ITC and ISRA)*EO was statistically significant at 10% α-level. This study
will enhance the skill set in Kenyan SMEs and produce a more sustainable solution.
Application of phytoplankton community structure for ranking the major riverine catchments influencing the pollution status of a lake basin
(John Wiley & Sons Australia, Ltd, 2020-01-24) Christopher Mulanda Aura, Cyprian Odoli, Chrisphine S. Nyamweya, James M. Njiru, Safina Musa, Jared Babu Miruka, Monica Ochieng Owili, Reuben Omondi, Phillip Raburu, Julius Manyala, Job Mwamburi, Zachary Ogari, Emmanuel K. Mbaru
The present study demonstrates the application of a multi-metric Phytoplankton
Index of Biotic Integrity (PIBI) approach for ranking of major river catchments in the
Kenyan part of Lake Victoria on the basis of their pollution status. The index utilizes water quality and zooplankton data, phytoplankton diversity, abundance and
attributes, as well as literature information. The rivers were sampled from 2016 to
2018 during the wet season (March) and dry season (July). The separation power of
the Mann–Whitney U test (p < .05) qualified eight discriminant metrics for phytoplankton samples into a scoring system of 1, 3 and 5, based on high, fair and slight
deviation from the best site, respectively, in development of the final PIBI. The Kuja
and Sondu-Miriu rivers had the highest PIBI, signifying least pollution influence on
the lake. In contrast, the Yala and Nzoia rivers exhibited the lowest PIBI, representing the catchments with a higher pollution influence on the lake. The fair to poor
integrity classes for the major river catchments in the region signified a deteriorating
lakescape. The present study presents the preliminary results of using phytoplankton
metrics for development of the Index of Biotic Integrity (IBI) approach in the region
as a decision-making support tool for the effective management and sustainable use
of water resources in the lake basin.
