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Cultural orientations as antecedent of customers’ perceptions of banking services: evidences from Tanzanian banking industry
No full textArticleThe paper examined how the cultural orientations influence customers’ perception on the banking services offered in
the Tanzanian banking by carrying out a comparison between foreign and local banks. The sample size of 380 customers
were involved, of whom 196 used local banks services while 184 used foreign bank services. Confirmatory factor
analysis was used to examine the psychometric properties of cultural orientations as based on the Tanzanian bank
customers. Validity and reliability assessment as well as measurement invariance testing were performed on the cultural
orientations’ measurement models used in the study. In carrying out the confirmatory factor analysis, Sharma’s (2010)
cultural orientation scale was applied and, the dimensions consumer innovativeness, traditional values and prudence
values were used in the model. The findings indicate that Foreign bank customers had significantly higher mean values
than local bank customers for consumer innovativeness and traditional values, but there was no significant difference
between the two types of banks for prudence values. The findings of the study suggest that there are significant
differences in the consumer innovativeness between local and foreign bank customers, with foreign banks customers
having significantly higher latent mean consumer innovativeness scores than local customers. There were no significant
differences between local and foreign bank customers based on prudence values. Surprisingly, foreign bank customers
had a slightly higher significant mean traditional values than local bank customers. The study recommends that Bank
managers should change the strategic focus of their offerings by identifying the exact customers’ needs, incorporating
cultural values so that these needs can be met and exceeded
Effect of water velocity on ammonium and nitrite removal in pilot scale fixed bed biofilters
No full textThe effect of water velocity on nitrification rates in fixed bed biofilters was investigated in three freshwater pilot scale RAS with rainbow trout. Removal of total ammonia nitrogen (TAN) and nitrite-nitrogen were assessed by NH4Cl spikes and tested at four different water velocities in the biofilters (1.4, 5.4, 10.8 and 16.2 m h− 1) under identical conditions. Water velocities below 10.8 m h− 1 significantly reduced TAN- and nitrite removal rates. The surface specific TAN removal rates correlated with the TAN concentrations at the water velocities 10.8 and 16.2 m h− 1, and the first order surface removal rate constant was estimated at 0.45 m h− 1. However, no correlations between TAN removal and TAN concentrations were found at the lowest velocities. Up to five-fold elevated nitrite levels were found in the RAS when biofilters were operated at 1.4 m h− 1 compared to the trials at other water velocities, substantiating the significant effect of water velocity on both nitrification processes. The importance of biofilter hydraulics documented in this pilot scale RAS probably have implications for design and operation in larger scale RAS
Development of a model for integrated anaerobic digestion, solar and wind energy system for rural semi-arid areas
No full textThesisDevelopment of a model for integrated anaerobic digestion,
solar and wind energy system for rural semi-arid areasThe availability of sufficient energy and its efficient use is a primary factor in improving
and sustaining the economic and technological development of any community. However,
there are several challenges related to access to sustainable energy in the countries of Sub-
Saharan Africa (SSA). Inadequate access and connectivity to affordable, sufficient, and
clean energy for off-grid rural communities remain a major limiting factor for
development. For instance, only 15% of rural communities in SSA have access to
electrical energy, which indicates the severity of the problem. SSA countries have initiated
efforts to address the challenge. For instance, Tanzania has progressed by increasing
access to energy for the rural population from 49.3% to 69.8% from 2016/2017 to
2019/2020. However, the challenge is still far from being addressed; therefore, more
efforts are required to address them. Efficient exploitation of renewable energy resources
and sources (RERS), which are readily available in most rural communities of SSA, would
be ideal for reducing the challenge of limited energy access and connectivity. However,
the RERS have not been adequately utilised in rural communities. The major challenge for
insufficient use of RERS in rural communities is the high cost and inefficiency of
available RESRS technologies. The technology must be affordable and efficient while it
generates clean energy from the use of RERS.
Different countries have taken several initiatives to curb the challenge of insufficient use
of RERS in SSA. For instance, in Tanzania, a continuous fed fixed dome biogas
technology of 4-6 m 3 digester capacity was introduced in rural semi-arid areas of Dodoma
under the subsidy scheme. However, the technology had limited adoption because the
system was too expensive for low-income communities; also, the system had technical and
operational constraints. One of the constraints included difficulties in troubleshooting
faults in the digester system since the digesters were installed underground to reduce their
temperature variation. Another constraint was scarce water in the area since a large
quantity of water was required to run such systems. Therefore, further research for
alternative affordable and efficient renewable energy systems as part of the efforts to
reduce energy scarcity was necessary.
Consequently, this study sought to develop a novel integrated anaerobic digestion, solar,
and wind energy system, simply the i-SWEAD system. The system generates energy for
households in rural semi-arid areas. The system’s affordability and efficiency were
essential targets to be met. The study was conducted in the Idifu village of Dodoma,
Tanzania, as a representative of the semi-arid areas of SSA. Four specific objectives were
set and executed to achieve the study aim. These specific objectives were to (i)
characterise the available renewable energy-related resources and variation in ambient
temperature, (ii) design and test the functionality of the i-SWEAD system, (iii) model the
biogas production of the i-SWEAD system, and (iv) conduct a techno-economic appraisal
of the i-SWEAD system.
Characterisation of the available renewable energy-related resources and the ambient
temperature was done in the following manner. Firstly, the cow dung samples were
collected from the study site and analysed in the laboratory to determine their chemical
and compositional properties using proximate and ultimate biomass analysis methods.
Secondly, solar irradiance, wind speed, wind direction, and ambient temperature were
measured using a weather station installed at the study site. It was found that the available
cow dung contained essential qualities (volatile matter of 744.3± 53.2 g/kg of dry matter
and a Carbon Nitrogen ratio of 19.3) for biogas generation. Also, the amount of solar
energy (solar isolation of above 4.5 kWh/m 2 /day for seven months in a year) and wind
energy (average annual wind speed of 4.69 m/s at 4 m hub height with predominant wind
direction from North East) were adequate. However, the ambient temperature variation
was ±4.04 o C within a day, which poses a challenge for adopting a biogas generating unit
installed on or above the ground without heat insulation features. Therefore, the design of
the i-SWEAD system must consider the limitation in temperature variations.
As a result, the i-SWEAD system was designed to meet the functional requirement of
producing biogas and electricity. An anaerobic digestion system was designed and resulted
in an Adapted Batch-Fed Anaerobic Digestion (ABFAD) system to curb limitation in
biogas clogging; then, the ABFAD system was integrated as a sub-system of the i-
SWEAD system. The ABFAD system was tested separately to check if it adequately
addressed the challenges of biogas clogging; also to establish its functional curves useful
for the system operating status indication. The results revealed that the system had
addressed those challenges and some other conventional biogas generation systems’
challenges. The data collected for pressure, pH, and dissolved oxygen during the testing of
the ABFAD system were useful in developing their functional characteristic curves.
Similarly, the i-SWEAD system was tested for its functionality. The results showed that
the system had an average biogas yield of 0.077 m 3 /kg of fresh cow dung (0.343 m 3 /kg of
cow dung dry matter) and methane content of 48.57±2.15%. Also, it had a biogas
production rate of 0.54 m 3 /m 3 of digester in a day. The i-SWEAD system kept its digester
temperature variation within 1.28 o C/day, which is tolerable to biogas microbes. Despite
the adequate performance of the i-SWEAD system, further analysis would make it robust
for adoption and upscaling. In that sense, modelling biogas production of the i-SWEAD
system becomes the core of its success in reaching a broad community.v
An Artificial Neural Network (ANN) modelling technique was used to model the biogas
production of the i-SWEAD system. The method was chosen because of its robustness,
and since the anaerobic digestion processes are non-linear, the ANN modelling technique
fits well. The ANN technique was used to generate six predictive models for the i-
SWEAD system. The models were evaluated to choose the best model, which can
adequately predict biogas production in the i-SWEAD system. The data used for training
the model and testing its performance were solar irradiance, wind speed, ambient
temperature, digester temperature, hydraulic retention time, and biogas volume. Data were
separated into two sets to train the model (75% of the data) and test the model (25% of the
data) using a random method. The model predictive power was evaluated using the
Absolute Model Predictive Accuracy (AMPA). It was found that the chosen model among
the six predictive models generated, i.e., Model4, was robust with the AMPA value of
99% for the i-SWEAD system. Therefore, the model gave the required predictive accuracy
in this study, implying that it can be adopted in decision making. Thus, the ANN
technique proved to be useful in building an appropriate model for the i-SWEAD system’s
biogas generation prediction. Both the technique and the model are recommended for
utilization.
Furthermore, it was necessary to conduct the techno-economic appraisal of the i-SWEAD
system to check if the system was efficient and affordable for the low-income
communities in semi-arid areas. Comparison was made to the ABFAD-solar system to
check if the i-SWEAD system was more efficient and affordable. The total energy
generated per year was quantified for both systems. It was found that the i-SWEAD
system produced higher energy (267 kWh/year) than the ABFAD-solar system (239 kWh/
year). The i-SWEAD and ABFAD-solar systems had the same digester size (0.24 m 3 ),
same solar PV module rating (20 Wp), while the i-SWEAD system had an additional windvi
turbine with the power rating of 54 Wp. The i-SWEAD system's capital investment was
TZS 1 136 000.00 or € 2017 494.00, while the capital investment of the ABFAD-solar
system was TZS 971 240.00 or € 2017 422.00 meaning that the latter is cheaper. However,
the Internal Rate of Return (IRR) analysis shows that the i-SWEAD system had an IRR
value of 16.6%, while that of the ABFAD-solar system was 10.4%. Therefore, the i-
SWEAD system was found to be more economical than the ABFAD-solar systems. The
costs of both i-SWEAD and ABFAD-solar systems are within the affordable range based
on the National Bureau of Statistics (NBS) of Tanzania. However, given the advantage of
the total energy production and value of IRR, the-i-SWEAD system can be considered a
better option.
The system is technically and economically justifiable as an efficiently feasible and
affordably viable project useful for contributing to energy accessibility, based on its
detailed techno-economic assessment results. Therefore, the system is novel, adequate,
and worthy of being promoted for adoption and upscaling after training users on how to
operate and test it in low-income communities of SSA’s rural semi-arid areas.Trans SEC Projec
Morphological characterization and yield of pepper (Piper nigrum L.) types grown in Morogoro District, Tanzania
No full textBackground: Pepper (Piper nigrum L.) is among key spice crops grown in Morogoro district of Tanzania. Most of the
pepper types grown in the district are only known by their local names as Babu kubwa, Babu ndogo, Babu kati and
Ismailia. This may limit information on germplasm collection or genetic resource for plant improvement and trade in
markets with variety specifications. The aim of this study was to generate preliminary information of the pepper types
based on their morphological characteristics for easy comparison with other known pepper varieties in the spices
industry.
Methods: The evaluation of pepper morphological characters was conducted following a randomized complete
block design with three replications and four treatments (pepper types). Observations were recorded with respect to
28 characters (9 qualitative and 19 quantitative) which entail vegetative (8) and reproductive (20) traits. The quantita-
tive data for vegetative, inflorescence and berry characters were subjected to analysis of variance. Mean separation
test was conducted using Turkey’s Honest Significance Test at (α = 0.05). Correlation and regression analyses were
performed to explore the relationship between yield and yield attributes of pepper.
Results: Babu kubwa and Babu ndogo pepper types were characterized by erect and horizontal branching habit,
whereas the others showed hanging habit. Babu kubwa had longer spikes (12.4 cm), leaves blade (17.9 cm), leaf
petiole (2.8 cm), wider leaves (12.9 cm) and larger berries (5.8 mm) than all other pepper types. Babu kubwa and Babu
kati had cordate and acute leaf bases, respectively while other types had round leaf base shapes. The highest number
of flowers was recorded on Babu kubwa (93.5) and Ismailia (90.7) with spikes weighing 7.6 g and 7.5 g, respectively
compared to other types. Babu ndogo and Ismailia had compact spikes, while other types had medium loose spikes.
Babu kati had the highest number of spikes kg −1 (282.6) due its lower spike weight compared to other types. The
highest weight of 100 fresh spikes (704.3 g) and 1000 fresh berries (164.2 g) was recorded on Ismailia. Spike length
was significantly positively correlated to yield (r = 0.23, R 2 = 0.08, p < 0.001). However, yield had a significant nega-
tive correlation with the number of spikes kg −1 (r = −0.85, R 2 = 0.017, p = 0.001) and fresh weight of 1000 berries
(r = −0.91, R 2 = 0.003, p = 0.04).
Conclusions: The pepper types grown in Morogoro district differed significantly based on most of the evalu-
ated traits. This information can be used to formulate methods and strategies for conservation and in turn genetic
improvement of the crop. Despite that the pepper types literary matched with characters of some well-known
commercial varieties, confirmation of genetic relatedness is yet needed. Further studies need to be conducted in consecutive years and involve assessment of internal quality attributes. Other studies should encompass wider range
of pepper types from other producing areas in Tanzania in order to establish their morphological distinctness, genetic
diversity and interrelationships in relation to the globally known commercial varieties
Effects of plant species diversity and biomass on grazing patch selection by semi free-ranging cattle
No full textTanzania Journal of Science 47(1): 2021, pp. 282-295Studies examining forage selection by large herbivores have generally focused on single
herbivore-plant relationships and few studies link plant species diversity with large herbivore
feeding preferences, particularly in species-rich ecosystems. A study was therefore conducted to
examine how herbaceous plant biomass, species richness, diversity and evenness, together with
elevation and distances to houses, agricultural fields and cattle holding-pen areas (kraals), predict
cattle grazing intensity at small (0.5 x 0.5 m) and large (20 x 50 m) patches by semi free-ranging
indigenous cattle in Kilombero Valley Floodplain wetland Tanzania. Results showed that cattle
grazed patches with high species richness and intermediate level of biomass at a small spatial
scale, suggesting that selection of small patches is a trade-off between food quality and quantity.
On a larger scale, cattle grazed patches with a higher abundance of palatable plant species with
high biomass, but with less plant species diversity. Moreover, grazing intensity in large patches
was positively related to elevation and distance from agricultural fields. Overall, this study shows
that considering both plant community properties and physiographic variables in forage selection
studies facilitates a better understanding of grazing ecology of large domestic herbivores in
species-rich ecosystems. Thus, maintenance of plant species richness and biomass in wetland
rangelands is important to improve domestic herbivore production and conservation of
biodiversity
Contribution of youth development fund-supported income generating activities to youth livelihoods in Morogoro municipality and Mvomero district, Tanzania
No full textDissertationThe extent to which - Youth Development Fund (YDF)-supported income-generating
activities contributed to youth livelihoods among beneficiaries is unknown, although it is
generally believed that -YDF has not managed to create employment opportunities among
youth since its establishment in Tanzania. This study aimed at establishing how - YDF
contributed to the improvement of youth livelihoods by examining the reasons behind the
choices of income-generating activities that youth who are the beneficiaries of YDF are
engaged in. The specific objectives were: i) To identify and characterize the YDF-
supported income-generating activities that YDF recipients are engaged in; ii) To
determine factors that influenced the choices youth make to engage in YDF-supported
income-generating activities; iii) To assess the contribution of YDF-supported economic
activities to youth livelihoods in terms of income, food security, and asset ownership of
the YDF recipients; and iv) To assess the effect of YDF-supported economic activities in
generating employment and strengthening community participation of the youth. Results
show that most of the critical factors were not considered when youth were choosing the
types of enterprises intending to engage in as YDF beneficiaries. However, YDF still has
been shown to contribute to the livelihoods of youth at P ≤0.01, leaving other factors such
as financial support from the family, friends, and personal saving constant. Finally, it was
concluded that YDF has contributed to improving the livelihood of the youth beneficiaries
of YDF. However, it is recommended that the sum of funds provided should reflect the
enterprise selected by youth and more options on how funds can be accessed should be
added, such as individual loans and equipment or machinery loans.Sebastian Kolowa Memorial University (SEKOMU)
Khery Sang
An exploration of rural communities’ response towards joining the Improved community health fund (iCHF): A case of monduli juu ward, Tanzania
No full textJournal ArticleThere are a number of efforts by the Tanzanian Government to promote accessible and
equitable health services to deprived rural communities throughout the country. The
government, among other things, has been mobilizing various stakeholders to contribute to
the provision of health services to poor rural communities through community based health
insurance schemes. However, the provision of health services, through health insurance
schemes, continues to face poor response from the intended beneficiaries. Using a case of
Monduli Juu Ward, this study explored rural communities‟ response towards Joining the
improved Community Health Fund (iCHF). The study adopted a mixture of cross- sectional
research design and Participatory Action Research (PAR). The collected data were analyzed
by using SPSS and content analysis. Overall, the findings show that there are several
issues that affect the extent of rural communities‟ response to joining the schemes. Lack of
awareness and the prevalence of poverty among households have been proven to gravely
block a number of households from joining the scheme. It is recommended that the
government and other stakeholders should work closely with poor rural communities to create
economic empowerment programs and massive awareness campaigns. The measures will
enable the local communities to improve their socio - economic wellbeing as well as to awake
them on the benefits they would have obtained by joining the iCHF. Finally, PAR is
instrumental in the mobilization of communities for them to own the process
Profit efficiency of smallholder wine grape farmers in Dodoma city and chamwino district in Dodoma Region, Tanzania
No full textPhD ThesisGrape is one of the most important economic fruits crop grown in Dodoma Region -
Tanzania. However, grape production faces challenge of low yield of 5.6 t/ha compared to
the established yield potential of 25 t/ha under irrigation and 17.3 t/ha under rain-fed in
Tanzania. This low productivity was mainly due to rising cost of production, which is
coupled with low output prices and an unreliable market. The most cost effective way to
improve farm productivity is through efficient use of available scarce resources and
technology. This study was conducted to analyse farm level profitability, profit efficiency
and identify specific factors that account for variation in efficiency among farmers. The
study also analysed farmer`s factor demand response due to changes in input prices. Multistage,
stratification and random sampling techniques were used to select 176 farmers from
irrigation and 183 farmers from rain-fed production systems. A structured questionnaire
was used to collect data. Descriptive statistic, farm budgeting technique and a stochastic
profit frontier were used to analyse the data. The results revealed that irrigated farms were
more profitable compared to rain-fed farms. The findings show further that wine grape
farmers are not fully profit efficient, implying that an opportunity exists to increase profit
efficiency through better use of available resources. On average irrigated farms are more
efficient (69%) compared to their rain-fed counterparts (63%). A farmer`s experience,
group membership, access to extension and credit service are key factors that significantly
influence profit efficiency among farmers. In the short-run the coefficients for own price
of labour, manure and agrochemical are inelastic. Policy measures directed at providing
credit and extension service to enhance the farm`s profit efficiencies are recommended. In
addition, any support to facilitate formation of farmers` association is very important
because membership in such groups can benefit farmers through economies of scale,
thereby reducing each member’s production cost. Reducing the cost of labour and
agrochemical can significantly increase the farmers’ profit level. Moreover, agricultural
policies directed at developing irrigation schemes to enhance grape productivity in order
to improve farm income and profit is recommended.The Local Government Training Institute (LGTI
Effectiveness of tomato postharvest processing Technologies by boiling and solar drying for small scale Processing in Morogoro region
No full textThis study determine effectiveness of tomato postharvest processing technologies by
boiling and solar drying for small scale processing based on nutritional and sensory
quality. Tomato sample varieties Asira, Imara and Reogrande were collected from small
scale farmers in Morogoro region for tomato paste and powder development. Nutritional
quality was determined based on moisture, lycopene, ß-carotene and ascorbic acid
contents, titratable acidity and pH. Sensory properties were determined using Quantitative
Descriptive and Affective Analysis by assessing the level of consumer profile and
acceptability of juices and soups prepared from fresh tomato, paste and powder using
9-point hedonic scale. Data were analysed using R-software significantly at p 0.05.
The initial moisture content (MC) in fresh weight basis (FW) for three varieties ranged
from 92.97 0.31 to 95.12 0.12% in fresh tomato, 68.97 0.32 to 71.73 0.48% in
tomato paste and 11.02 0.09 to 11.74 0.41% in tomato powder samples. The lycopene
contents varied from 6.11 0.26 to 7.34 0.02 mg/100g, 8.12 0.25 to 8.81 mg/100g and
10.57 0.01 to 11.30 mg/100gFW in fresh tomato, paste and powder, respectively.
The β-carotene content ranged from 1.46 0.18 to 2.33 0.04 mg/100gFW in fresh
tomato, 2.57 0.17 to 2.91 mg/100gFW in paste and 3.19 0.01 to 3.26 0.03
mg/100gFW in powder. The ascorbic acid content ranged from 10.64 to 12.67 1.76
mg/100g in fresh tomato, 2.03 0.88 to 5.83 0.44 mg/100g in paste and 48.13 2.32 to
51.93 4.19 mg/100g in powder. The titratable acidity (%citric acid) ranged from 0.30
0.07 to 0.38% in fresh tomato, 0.64 to 2.23 0.07% in paste and 6.23 0.30 to 6.48
0.15% in powders. The pH ranged from 4.50 to 4.66 in fresh tomato, 4.56 to 4.68 in paste
and 4.76 to 4.95 in powder. The results indicate significant difference between tomato
products in terms of nutritional content as an effect of processing and individual variety.
Therefore, tunnel solar drying of fresh tomato into powder concentrates nutrients contents
in comparison to boiling into tomato paste. Boiling fresh tomato into paste retains better
nutrients but due to physical removal of skin and seed some of the nutrients were lost
along the process. The Quantitative Descriptive Analysis (QDA) showed that, juice from
fresh samples had significantly higher colour intensity scores 8.50±0.80 (like
very much), paste was aromatic rated 8.10±1.00 (like very much) and powder liked very
much due to acidity, consistency, sweetness, viscosity and clarity rated with 3.20±1.27,
8.30±0.49, 8.10±1.38, 7.70±0.89 and 8.30±0.49, respectively. Overall acceptability of
juice sample from Paste_Asira and Powder_Asira were the most acceptable by consumers
with hedonic scores of 7.00±1.97 and 7.00±2.02 (like moderately).
Furthermore, soup from Fresh_Imara had significantly colour and reddishness intensity
score 8.30±0.65 and 8.20±0.58, respectively. Samples from Paste_Asira had aroma rated
7.60±1.17 while those from Powder_Imara was liked with acidity and consistency score
6.30±0.89 and 8.30±0.62, Powder_Reogrande with saltiness score 5.90±0.67 and
Powder_Asira with viscosity score of 8.50±0.52. Overall acceptability of soup samples
from Paste_Imara, Powder_Imara and Paste_Asira were the most acceptable by
consumers with hedonic scores of 7.40±1.30, 7.40±1.21 and 7.00±1.50, respectively.
Conclusively, juice and soup samples from powder and paste were moderately liked.Family and COSTEC
Etiology, incidence and management of "leaf yellowing syndrome" of rice (Oryza sativa L.) in Mvomero district
No full textMasters ThesisIntroduction
Rice (Oryza sativa L.) is a source of food and income to smallholder farmers in the
Mvomero district. Recently, however, rice farmers in the Mvomero district have been
experiencing a new leaf yellowing syndrome of unknown etiology, which is
associated with leaf yellowing, affected plant showing stunting reduced tillering and
low yield. This study was undertaken with the aim to establish the causal agent(s) of
the leaf yellowing syndrome and then develop sustainable measures for its
management. Specifically, the study sought to (i) determine the level of farmers’
awareness of and management practices for the leaf yellowing syndrome (ii) identify
the main causes of leaf yellowing syndrome of organic produced rice in Mvomero
District and (iii) develop sustainable management strategies for the leaf yellowing
syndrome. The second, third and fourth chapters in the dissertation comprise
manuscripts in the form of publishable papers which cover the first, second and third
specific objectives.
Methods
With respect to specific objective 1, a field survey was conducted between October
– November, 2018 in rice growing areas of Kimambila and Mingo villages in
Mvomero District. The aim was to determine the level of famers’ awareness of and
management practices for rice yellowing syndrome. A face-to-face interview using a
semi-structured questionnaire was conducted to gather primary information from 120
randomly selected farmers. Data were analyzed to determine the distribution of
respondents per variable using the Statistical Package for Social Sciences (SPSS)
program version 16. A Chi-square tests and regression analysis were computed at (P
≤ 0.05) level of significance, to analyze relationships between variables.
Objective 2; this part of the study was undertaken to identify the cause (s) of the
yellowing syndrome in Mvomero district. Rice seeds, leaves and soil samples were
collected from the villages under study for assessment. Seed health and seed quality
tests were determined using blotter method and agar plate method. Isolation of fungi
and biochemical tests of the fungal pathogens were conducted from randomly
selected symptomatic rice leaves. The soil samples were analysed for physical and
chemical properties following recommended procedures.
Pertaining to objective 3; a study was conducted at Mingo village in Mvomero
district, Morogoro region, Tanzania in 2019 aiming at improving rice performance
through enhanced soil fertility using organic fertilizers. A split–split plot experiment
in a randomized complete block design was laid out with four replications and two
factors. The main factor comprised of four rice varieties that included (i)
Mbawambili (ii) Mwangaza (iii) Supa and (iv) Saro while the sub factor consisted of
(i) Cow dung manure at the rate of 5t ha-1, (ii) Urea 46% N at a rate of 80 kg N ha-1
(iii) Compost at the rate of 5t ha-1 and (iv) No fertilizer (control). Rice was sown in
2m x 1m plots each with five rice rows at 20cm inter–and intra–row spacing. Data on
weather, leaf yellowing incidence, crop growth, yield components and grain yield
were collected. Data were subjected to the analysis of variance (ANOVA) using
Genstat 16th edition software (VSN International). Means separation test was
conducted using Turkey’s Honest Significance Difference Test using P≤0.05 as the
level of significance. A correlation analysis was calculated using Pearson product
moment correlation coefficient (r) using the Microsoft office-Excel programme to
explore the relationship between growth and yield components of rice.
Findings
Yellowing and stunting of rice were reported as predominant problems by 100% of
interviewed farmers. Lack of knowledge on rice leaf yellowing syndrome was
reported by all (100%) respondents as the main factor limiting the management of
the yellowing syndrome. Bipolaris oryzae and Fusarium moniliforme pathogens in
tested seeds were found to be predominant in all tested rice varieties. Soil pH was
found suitable for rice production; Nitrogen and Potassium were very low than the
suggested standards and therefore deemed deficient. Nitrogen deficiency in both sites
was the major causes of yellowing syndrome reported. Disease index results
indicated that all the fertilized rice varieties did not develop yellowing and stunting
syndrome. However, high incidence of the yellowing syndrome and plant stunting
were observed in the unfertilized control plots implying that N deficiency is the main
contributing factor to the leaf yellowing and stunting syndrome. There were
significant (p<0.01) effect in respect of varieties and fertilizer types used on growth
parameters and yields components. Further, regression and correlation analyses
showed positive correlation between yield and other growth parameters.
Conclusions and recommendations
Generally, lack of knowledge on the cause of rice leaf yellowing syndrome was the
main factor limiting the effective management of the syndrome in Mvomero district.
Several seed borne pathogenic fungi were found associated with rice seed samples
from Mingo and Kimambila villages and therefore indicate the possibility of disease
episode when such infected seeds are used to raise the next rice crop. Nitrogen
deficiency was confirmed to be the major cause of yellowing syndrome. Measures
should be taken to increase the availability of macronutrient in the soil especially N
and P in order to increase rice productivity. Uses of organic manure together with
other sustainable agronomic practice such as fallowing, intercropping, and planting
leguminous crops in the field alongside rice varieties will help adjust soil fertility
and spar rice yield. Mbawambili which is a commonly used local rice variety does
not fair favourably against Supa, Mwangaza and Saro with regard to yield and
yellowing syndrome. Therefore a breeding program to incorporate genes for higher
yield and disease resistance in the variety should be undertaken in order to increase
its disease resistance and yield potential