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Pattern analysis of substandard and inadequate distribution of educational resources in urban–rural areas of Abbottabad, Pakistan
No full textDespite an extensive system of public schools, Abbottabad, Pakistan has a chronically low literacy rate. A factor contributing to these low literacy rates might be a spatial mismatch between public schools and dense settlements in fast-growing urban
and semi-urban areas of this municipal region. To test this proposition, the locations of 153 public schools were collected using hand-held GPS devices to create a geo-database, and a road network was created from the open street map and Google imagery. Nearest neighbor, K-function, Spearman’s Rho, and directional analyses were applied to this data to overcome the limitations of sparse geospatial data. A point pattern analysis shows that more than 50% of secondary schools were clustered south of the city while most of the built-up area was in the north. Localizing Geospatial data, spatial restructuring, and reorganization of schools in the study area would support rational
planning and enhance student access to school facilities
Gendered influences affecting adoption of improved common bean production technologies disseminated by various awareness creation methods in Karatu district, Tanzania
No full textA Dissertation 2019The importance of common bean in improving socioeconomic in the community is well
known. There are different improved common bean production technologies introduced by
both government and NGOs in Tanzania such fertilizer application especially DAP during
planting. However, none or low adoption of recommended common bean production
practices like recommended land preparation, seed selection, weed control, fertilizer
application and harvesting method is reported everywhere. Cross sectional research design
was employed in this study whereby 400 respondents (154 males, 125 females and 121
youth men and female) involved in Scaling up of Improved Legume Technologies (SILT)
project and those who were not involved in SILT project were interviewed using
questionnaires and checklist questions as the main tools. Data were analyzed by using
statistical package for social science (SPSS 16.0), where frequency and percentage were
used to determine distribution of the study variables inferential analysis was used to test
how independent variables affect the adoption of improved common bean varieties. Result
from the study shows that accessibility of information through radio, demonstration and
extension agents was relatively high to men than women and youth. This was due to
interventions of SILT project. The study further revealed that farmers in SILT project
were aware on improved common bean technologies like improved seed varieties, storage
and harvesting than those who were not in SILT project. The study concludes that Men
have higher access to information on improved common beans production technologies as
compared to women, boys and girls. Therefore, the study recommends to the extension
workers and NGOs such as SILT that there is a need to address gender inequalities with
regard to ownership and control over resources and information sources at household level
which impacts on adoption of common bean. This can be achieved through using the
strategy of gender mainstreaming in all projects targeting farmers
Commercialization pathways and their implications on smallholder rice farmers’ productivity and welfare in Mbarali district, Tanzania
No full textA Dissertation 2019Agricultural transformation from low productivity to commercial agriculture has been a
policy of concern in Sub-Saharan African countries whose economies depend on
agriculture.
Different pathways to commercialization have been adopted, including
smallholder commercialization, medium and large scale commercial agriculture while
others have adopted inclusive commercialization. However, the existing literature is
inconclusive on which pathway should be adopted particularly in Sub-Saharan Africa.
This study aimed at evaluating the most effective commercialization pathway (smallholder
or inclusive) and its impacts on productivity and welfare on smallholder rice farmers in the
pathways versus rain-fed farmers in Mbarali District. The study used cross-sectional
survey data collected from a sample of 256 farm households. The data was analysed using
output and input commercialization indices (CCI and ICI) and propensity score matching.
Results indicated that, the overall output commercialization was more than half of the
produced rice (CCI=59%) but the use of improved inputs in the study area was low (ICI =
27%). The proportion of rice sold was higher in the inclusive pathway (80%) relative to
smallholder pathway (70%) and rain-fed scheme (41%). Total factor productivity ranged
between 1.17 - 1.21 and 0.98 – 1.02 in the smallholder and inclusive pathways
respectively more than the in the rain-fed scheme. Farmers in the smallholder and
inclusive pathways earned between 7.65 – 7.68 million and 5.42 – 5.48 million TShs
respectively more than farmers in the rain-fed scheme. For dietary diversity score, food
consumption score and value of assets, inclusive pathway was better-off relative to
smallholder pathway and rain-fed farmers. Based on these findings, smallholder pathway
was effective in rice total factor productivity and income earned while the inclusive
pathway was most effective in commercialization and welfare improvement. Since each
pathway has some positive impact relative to the other, both smallholder and inclusive
pathways should be adopted to explore the synergies
Persistent organic pollutants in water, sediments and fish from Lake Victoria and implications to human health risks
No full textThesis 2019Lake Victoria is an important freshwater resource in Tanzania and its neighbouring
countries namely Uganda, Kenya, Rwanda, Burundi and Democratic Republic of Congo
(DRC). Millions of people dotted around the lake depend on it as a major source of
household and industrial water supply, irrigation, transport and provides for fishing as a
main source of animal derived protein as well as income. In Tanzania, the lake provides
employment opportunities to more than four million people engaged directly or indirect
with fishing activities. The frequently fished and consumed fish species that are of commercial interest include; Nile perch (Lates niloticus), Nile tilapia (Oreochromis niloticus) and the freshwater sardines (Rastrioneobola argentea) commonly known as
dagaa in Tanzania. The fish are further processed to feed the domestic, regional and
international markets. Current estimates from the lake put the annual contribution of the
fisheries sector to the Tanzanian Gross Domestic Product (GDP) up to 2.5%.
There have been unsubstantiated claims that despite using agrochemicals such as
pesticides in agriculture, some fisher folks have been using such chemicals for fishing and
preservation of fish products during storage. The same organochlorine pesticides are still
in use in agricultural activities within the lake basin and there is a possibility that they
accumulate in water, sediments and fish. Furthermore, there have been incinerations of
medical wastes, discharge of electronic wastes and untreated wastewaters from industrial
establishments in water bodies that tend to increase the loading of polychlorinated
biphenyls (PCBs) in water, sediments and fish. It is likely that human beings will get
exposed to these chemicals through drinking water and eating fish from the lake.
The present study overall objective was therefore to assess fish consumersꞌ eating habits
and the prevalence, levels and human health risks of indicator PCBs and OCPs in water,
sediments, fish and fish products from Lake Victoria in Tanzania.
The specific objectives of the study were:
i.
To establish levels of indicator PCBs and OCPs in water, sediments and fish from
Lake Victoria.
ii.
To determine the prevalence and quantify residual levels of indicator PCBs and
OCPs in processed fish products from Lake Victoria.
iii. To assess fish consumersꞌ eating habits.
iv. To evaluate the probable human health risks associated with consumption of
persistent organic pollutants (POPs) contaminated fish and fish products from
Lake Victoria.
Water and sediment samples were collected from twelve nationally designated sampling
points (considered as important hotspots). Thirty six samples of both water and sediments
(a total of 72 samples) were collected for analysis. A total of 162 fresh fish samples were
collected from nine selected landing sites and 480 samples of processed fish products
from Kirumba Fish Market for analysis of POPs. Extraction of the samples was done
using a QuEChERS method and POPs analysis using a gas chromatography equipped
with electron capture detectors (GC-ECDs) and a gas chromatography equipped with
mass spectrometry (GC-MS).
A questionnaire was also administered to 122 fish consumers to assess the fish
consumption habits and patterns. The main focus of administering the questionnaire was
to identify the types of fish species consumed, frequencies of fish consumption, quantities
of fish consumed and factors affecting fish consumption in the population around the
lake.
The results showed that some organochlorine compounds were present in water,
sediments, fish and fish products from Lake Victoria in Tanzania. This is likely due to
human anthropogenic activities being undertaken along the lake, long range atmospheric
transport and environmental persistence of the compounds. For water samples, the
∑PCBs ranged between 0.95 and 2.24 μg/L while for sediments the range was between
<LOD and 10.28 μg/kg- dry weight (dw) basis being dominated by CB 138 and CB 153
because of their structures and high degree of chlorination. For OCPs; Aldrin and
Dieldrin were the highest (6.13 ±0.90 and 6.82±0.53 μg/kg- dw, respectively) and p,
pꞌ- DDT was the lowest (0.82±0.12 μg/kg- dw) in sediments whereas for water samples
the highest concentration was γ- HCH (1.60±0.32 μg/L) and the lowest was α- endosulfan
(0.15±0.01 μg/L).
There were high levels of organochlorine compounds in sediments than the water samples
suggesting that sediment serves as a sink for organochlorine pollutants and therefore act
as a source of these compounds in case of environmental changes. However, the levels of
POPs measured in water and sediments in this study were far below the Maximum
Residual Limit (MRL) set by FAO/WHO and the European Union (EU) except Aldrin
and Dieldrin through which based on the Threshold Effect Concentration (TEC) for
freshwater ecosystems, Aldrin and Dieldrin are the only OCPs that seem to be a threat to
Lake Victoria environment.
For the fresh fish species which were considered in the current study; L. niloticus and O.
niloticus, the results revealed that fish species sampled were undersize, reflecting
overfishing and abuse of bylaws.
The abuse may be going beyond overfishing and touching other environmental protection
bylaws. The results showed further that four organochlorine pesticides (β-HCH, HCB,
Aldrin and Dieldrin) were identified in fresh muscles of L. niloticus and O. niloticus at
measurable quantities at concentration between <0.24 and 1.19 μg/kg. There were slightly
higher levels of the identified OCPs in L. niloticus than in O. niloticus muscles due to
differences in trophic levels and feeding habits. However, the levels of OCPs measured
were below the MRL of 200 μg/kg set for fish by FAO/WHO and other competent
authorities suggesting that the fresh fish muscles were safe for human consumption.
The seven indicator PCBs considered in this study were not detected in all fresh fish
species investigated. Low levels of the detected residues and non detection of many POPs
which were considered indicates that currently POPs pollution in Lake Victoria has not
reached alarming concentrations but requires a strict continuous monitoring to minimize
contaminants loading.
Nine OCPs were detected at different measurable concentrations in different processed
fish products available in the markets from Lake Victoria. The highest amount was p, pꞌ-
DDE (3.73±0.31 μg/kg) in deep fried O. niloticus while the lowest level was α- HCH
(0.14±0.06 μg/kg) in smoked O. niloticus. The OCPs were more prevalent in smoked
products compared to other processed fish products. This is attributed to a reduced co-
distillation of the compounds with water vapour during smoking. However, there was
high prevalence of some OCPs in deep fried products compared to other fish products.
This is probably due to illegal use of some of these chemicals for fish preservation during
storage. In this study, the levels of OCPs in processed fish products were below MRL set
by different international statutory bodies for fish and fish products implying that the fish
products are safe for human consumption with reference to OCPs concentrations.
For the seven indicator PCBs which were considered in this study, six of them were
detected at different levels in processed fish products. The total PCBs loading ranged
from 16.05±3.04 μg/kg (deep fried products) to 31.55±16.66 μg/kg (trims). There was a
significant difference (p<0.05) in PCBs loading for deep fried products (with significantly
lower levels) compared to other products which were investigated in this study.
This observation is mainly because at high temperatures, cooking oil serves as an
extracting solvent and therefore the PCBs are transferred the cooking oil. The PCBs
loading was dominated by CB 138, CB 153 and CB 180. The same PCBs were more
prevalent (between 20% and 80%) in all fish products than other congeners. This is
mainly due to their structures, chemical stability and high degrees of chlorination.
However, the mean levels of ∑PCBs in this study were below the MRL of 75 μg/kg set
for fish and other fish products by the European Commission indicating that the products
are safe for human consumption with respect to indicator PCBs.
Lifetime cancer risks for both OCPs and PCBs in adults and children were low while the
non cancer risks associated with consumption of contaminated fish and fish products were
insignificant as the hazard indices (HI) were very low (<1). The risk is considered
significant if HI is greater than 1.
Results on fish consumer’s preferences, quantities and types of fish consumed and factors
affecting fish eating habits in this study showed that L. niloticus, O. niloticus and R.
argentea are widely consumed fish species. The average per capita fish consumption pervii
day was quantified to be 0.37 kg (~135 kg/year). This level is far greater than the
national, worldwide and the per capita fish consumption of a great fish consumer reported
in literatures. The main reasons for this high fish consumption in the study area were
found to be easy accessibility and availability of different fish species.
The major factors affecting fish consumption habits were reported to be price
(affordability), convenience, accessibility, availability, nutritional and healthy concerns.
The study revealed a slightly higher proportion of male fish consumers (54.1%) than
female fish consumers (45.9%) implying that males usually eat outside their homes better
meals than home meals. The study revealed further a direct relationship between fish
consumption and age of consumers due to knowledge and health reasons and an inverse
relationship between fish consumption and family size due to economic reasons. In order
to determine the actual human health risks associated with consumption of fish products
from Lake Victoria for consumers dotted around the lake, it is therefore necessary to
employ the actual per capita fish consumption of 0.37 kg established herein for risk
computation rather than the hypothetical per capita fish consumption rate of 0.02 kg
reported in literature.
Data generated from this study will therefore help decision makers to devise more
appropriate and cost effective risk mitigation measures that will minimize the build-up of
these organochlorine compounds in the aquatic ecosystems to safeguard consumer's
health and the environment. The results will also help to create awareness of the actual
adverse effects associated with the established organochlorine compounds among stakeholders in the fisheries sector
Incidence and molecular characterization of common bean (Phaseolus vulgaris L.) viruses in Tanzania
No full textA Dissertation 2019Common bean (Phaseolus vulgaris L.) is an important crop grown worldwide. It serves as a main
source of protein and starch for over 300 million people in East Africa and Latin America. Despite
its importance, production of common bean is constrained by viruses which cause important
diseases of common bean. It is also known that different common bean genotypes respond
differently to different viruses. In order to ascertain this information, the following specific
objectives were established: (1) to characterize common bean viruses isolated from common bean
using sequencing molecular techniques, (2) to determine the incidence and distribution of major
viruses of common beans in Tanzania, (3) to characterize at molecular level and identify the wild
plants harbouring the viruses infecting common beans in Tanzania, (4) to determine the suitable
sizes of reads from deep sequenced small RNAs data for VirusDetect software-based detection of
common bean viruses using low capability computers, (5) to determine genetic diversity of common
bean cultivars and landraces using diversity array technology (DArT) in Tanzania, and (6) to
evaluate the response of selected common bean genotypes to four common bean viruses in
Tanzania. A total of 7756 common bean samples were collected during survey from five agricultural
research zones, while 1340 wild plants samples were collected in four zones except western zone.
Total RNAs were extracted using Cetyl trimethyl ammonium bromide method (CTAB). The
symptomatic and asymptomatic common bean and wild plant samples were selected and pooled
according to their respective zone. Nine and 10 pooled common bean and wild plants, respectively,
including the wild plant samples (AIVN-1, AIVN-2 and AIVN-3) that were used in virus
mechanical transmission study were sent to Fasteris SA (Switzerland) sequencing company, where
small RNAs were sequenced using Illumina HiSeq 2500 platform. However, in wild plants was
done on Illumina HiSeq 3000/4000 or Illumina NextSeq platform. Analysis of NGS sequences
using VirusDetect Software revealed, 15 viruses, belonging to 11 genera, in the nine pooled
common beans RNA samples. Two viruses namely, SBMV and Tomato leaf curl Uganda virus related Begomovirus were detected for the first time in common bean in Tanzania. In wild plants,
NGS detected 122 viruse species in 20 genera. Out of these 122 viruses, 23 viruses from 12 genera
were related to viruses known to infect common beans. Peanut mottle virus (PeMoV) and Yam bean
mosaic virus (YBMV) were some of the viruses that were detected by RT-PCR in Senna
occidentalis and Senna hirsuta, respectively. In mechanical inoculation study, out of 25
symptomatic wild plants samples only four wild plants which belonged to two plant species:
Ocimum basilicum L. and Bolusafra bituminosa (L.) Kuntze, were able to infect common beans
with Cucumber mosaic virus and a bromovirus closely related Cowpea chlorotic mottle virus,
respectively. The wild plants RNA (collected from zones and those used fro mechanical
inoculation), were identified by DNA barcoding. However, attempts to sequence 134 PCR products
were only successful in only 89 (66.4% success rate). The DNA barcoded plants (89) belonged to
50 plant species. Using RT-PCR, detection of BCMV, BCMNV, CPMMV and SBMV viruses in
common bean samples was done. The amplicon were scored to determine the incidence of viruses.
Visually assessed field incidence of common bean viral diseases was as high 98%, in Missenyi
district. The highest RT-PCR based incidence of BCMV and BCMNV were 36.7% and 76.7%,
respectively. The incidence of SBMV ranged from 0 to 90.9%. In northern zone, the highest RT-
PCR based SBMV incidence was 10%. The RT-PCR-based CPMMV incidence was highest in
eastern zone where the incidence was as high as 46.7%. Also, using primers designed to NGS-based
sequences, incidence of five viruses from wild plant (BCMV, BCMNV, CPMMV, YBMV and
PeMoV) was determined in 1 430 wild plant samples by RT-PCR. Contrary to NGS results, BCMV,
BCMNV and CPMMV were not detected in any wild plant samples. On the other hand, YBMV and
PeMoV were detected in three and one wild plant samples, respectively. Genetic diversity of
isolates of BCMV, BCMNV and CPMMV from common bean RNA samples was achieved through
Sanger sequencing. The obtained nucleotide sequences encoding coat proteins of BCMV, BCMNV
and CPMMV isolates revealed they were 90.2 to 100%, 97.1 to 100% and 82.9 to 99.1% similar to each other, respectively. Some isolates, e.g., TZ:Mor 533:2015, had hallmarks of recombination
events. In separate study a total of 360 common bean genotypes were grown in screenhouse and
DNAs extracted using a CTAB method for genetic diversity analysis using the Diversity array
technology (DArT). A total of 35 047 markers were identified of which 558 (1.6%) markers were
highly informative. The genetic diversity dendrogram showed that, 278 and 82 common bean
genotypes grouped in the Andean and Mesoamerican gene pools, respectively. Principal component
analysis (PCA) based on genetic similarity confirmed that the genotypes belonged to two groups
(252 genotypes) and their variation was 82.2%. When PCA was determined separately for the
Andean and Mesoamerican gene pools, the within similarities were 82.94% and 84.60%,
respectively. The response of common bean genotypes to BCMV, BCMNV, SBMV and CPMMV
was studied in screen house using a Complete Randomized Design (CRD). Data on disease severity
and area under disease progress curve (AUDPC) were subjected to one-way analysis of variance
(ANOVA) and post-hoc analysis was done by using Tukey’s test. Depending on the common bean
genotype assessed, the symptoms appeared between 7 th and 12 th days post inoculation for all four
viruses. Across all viruses used, disease severity was less than 50% in most common bean
genotypes. The AUDPC ranged from 414 – 2 667, 0 – 1 586.7, 105.6 – 1 561.7 and 506 – 2 037 for
BCMNV, BCMV, CPMMV and SBMV, respectively. Resistance to all four viruses ranged from
susceptible to moderate resistance in inoculated common bean genotypes. However, Fibea and
Selian 05 did not develop any symptoms when were inoculated with BCMV (AUDPC = 0). This
work represents the first comprehensive surveys of common bean viruses in Tanzania using the of
state-of-the-art next generation sequencing technique to simultaneously detect all viruses in
common bean samples from five agricultural research zones in Tanzania. Using molecular
information, primers were developed, optimized and used to detect viruses – including BCMV,
BCMNV, CPMMV, and SBMV – in common bean and wild plants. The incidence of different
viruses was determined and the distribution of common bean viruses was mapped
Rodent diversity and habitat association in Handeni Hill Forest Reserve, North Eastern Tanzania
No full textA Dissertation 2019The distribution and diversity of rodents is influenced by various factors such as
vegetation characteristics, climatic conditions, disease, predation and habitat modification
due to anthropogenic activities and food abundance. This study was conducted in Handeni
Hill Forest Reserve from November 2018 to March 2019 with the aim of assessing the
influence of habitat characteristics on the abundance and distribution of rodent species.
Four permanent grids of 70 m by 70 m with 49 Sherman live traps were established in
miombo woodland and evergreen forest habitats respectively. In each habitat type one
pitfall drift fence was also established. A total of 102 individuals of 8 rodent species from
4704 traps nights were captured namely Praomys sp, Gerbilliscus vicinus, Grammomys
dolichurus, Rattus rattus, Mastomys natalensis, Acomys wilsonii, Lemniscomys rosalia
and Mus minutoides. Species such as G. dolichurus were restricted to the thickets in the evergreen forest and Praomys sp was restricted in a higher altitude of the Miombo woodland habitat. The canonical correspondence analysis (CCA) was used in showing a relationship among species, grids and habitat characteristics. The CCA ordination plot revealed factors such as shrub height, moisture and ground cover to have influence in species diversity and distribution. The study concludes that habitat factors such as ground cover and shrub height have strong influence on the species abundance in the area followed by moisture content
Members' participation and financial performance of wheat producers' cooperative societies in southern Ethiopias
No full textCurrently, cooperative enterprises in Ethiopia are growing in terms of numbers and
membership. However, despite growing policy attention and researchers‟ interest on
cooperatives, the issue of members‟ participation, in relation to performance of
cooperatives has not been adequately addressed. The overall objective of this study was to
determine the influence members‟ participation in their cooperative financial performance
of cooperatives. The study used a cross-sectional research design. Questionnaires and key
informant interview checklist were used for data collection. The study covered 371
members from 27 primary cooperatives. Participation attitudes were assessed using likert-
scale items, while members‟ evaluative perceptions about their cooperatives performance
were measured by using five score scale measurement. Multiple linear regression were
employed to analyze the relationship between participation and financial performance of
wheat growers‟ cooperatives. The study results show that majority of respondents have
positive attitude of participation in their cooperatives. Years in membership, number of
shares, quantity of seed purchased and quantity of wheat supplied were statistically
significant relationship with performance. Overall, on average members evaluated their
societies‟ functioning as good performance. Majority of respondents agreed that they are
better off in the market after joining cooperatives. It is recommended that since members‟
attitude and behavior of participation is affected by the level of information and education,
launching of a continuous cooperative extension education is critical. Strengthening those
participation aspects having influence on the financial performances. The good
performance of agricultural inputs provision service should be considered as best practice
of lesson and internal strength. Cooperatives should be able encouraging members to
supply more quality produce to their cooperatives by giving them tangible benefits in price
reward and patronage dividend. The study indicates issues for further study such as how
to address the financial capacity limitation of primary cooperatives and how to explore and
implement tri-modal arrangement in the form of public-cooperative-private partnership
model.
Key words: cooperatives, members, participation, performanceSasakawa Africa Fund for Extension Education (SAFE
Fuelwood efficient stoves as strategies to adapt the effects of climate change in Muheza district, Tanzania
No full textA Dissertation 2019The study was conducted in Muheza district, Tanzania to assess the fuelwood efficient
stoves (FWES) as strategies to adapt to climate change effects. Specifically, the study
assessed the extent of adoption of fuelwood efficient stoves, examined the direct and
indirect benefits of the stoves in the context of climate change adaptation and determined
the challenges of adoptions and up-scaling the FWES technology. Data were collected
through household’s questionnaire survey, checklists, and direct observations. Descriptive
statistics and logistic regression model were used in the study. Findings showed that about
77% of households adopted the fuelwood efficient stoves. Five types of cooking stoves
were observed in the area; improved stove with and without chimney, gas stoves, charcoal
and three stones-traditional open stoves. Firewood consumption, low emission of smoke
and restoration of landscapes were among the direct and indirect benefit of using the
fuelwood efficient stoves in adapting to climate change effect in the area. Binary Logistic
Regression Model Analysis (R 2 =0.73, F=9.57, p<0.05) revealed that age and fuelwood
scarcity significantly showed a positive linear relationship with FWES adoption. T-sample
test show that the average of the head load of fuelwood used per week by households after
and before the introduction of stoves were statistically different. Results also revealed that
adoption of stoves is the best strategy for communities in order to adapt to climate change
effects in the area by reducing disturbances on the forest resources. Nevertheless, limited
knowledge about the stoves and its usefulness in relation to climate change effects was
among of the challenges for adoptions of the stoves in the area. Therefore, the adoption of
fuelwood efficient stoves by the local communities in the area has assisted them to adapt
on the effects of climate change while addressing the scarcity of fuelwood in the area and
improving their livelihoods
Cassava value chain: willingness to pay for improved cassava planting material in coastal and Lake Victoria areas of Tanzania
No full textMasters DissertationLack of clean planting materials and use of Cassava Mosaic Disease (CMD) and Cassava
Brown Streak Disease (CBSD) infected planting materials has been the major constraints
to cassava production thus communities need to be empowered to have a self-sustaining
clean seed production system. Therefore, agricultural policies of the countries in Sub-
Saharan Africa should therefore emphasize seed system strategies which would result in
good quality seed of the right varieties being available. There are many factors that hinder
cassava production among them is the unavailability of clean quality improved planting
material. To overcome the challenge of unavailability of clean quality improved planting
materials, it is envisaged that its production in large quantity and dissemination in
affordable manner is imminent. The production of such planting materials could be done
on commercial basis. Therefore, objective of this study was to assess i) the cassava
demand for industrial consumption; ii) the supply base of cassava planting materials; iii)
the cost of planting materials incurred by smallholding farmers in the study areas and iv)
to determine willingness of smallholding farmers to pay for clean quality improved
planting material (improved cassava seeds) when produced and made available to them on
commercial basis. The study found that 0 percent of the respondents obtain cassava
planting materials from formal seed system, 89 percent do use seed-system approved and
released planting materials and 99 percent obtain planting materials from their own
source. Also, it was not easy to directly determine the cost of planting materials per
hectare, though based on the survey conducted to determine willingness to pay for clean
quality improved cassava planting materials it was estimated that smallholding farmers in
the study areas would pay TZS 62 500 per hectare to obtain clean quality improved
cassava planting materials. It was also found that factors influencing the willingness to
pay were age, household monthly income, agronomic cost and residential location. The study also revealed wide range of cassava varieties which are grown in the surveyed
areas whereby some of them take long time to mature. The research implications of this
study are that the demand for improved cassava seeds creates opportunity for further
research into the area whilst the practical implications are that entrepreneurial opportunity
is available for investment into commercial production. Socially the results of this study
increase the knowledge that smallholding farmers are now willing to pay for improved
cassava seeds.
It was thus concluded that, although smallholding farmers showed
willingness to pay for clean quality improved cassava planting materials when
disseminated on commercial setting, the price they are willing to pay is much less
compared to what is currently charged by commercial cassava planting materials
producers under a pilot project are charging. Also, factors influencing willingness to pay
were age, household monthly income, area under cassava cultivation, agronomic cost,
CBSD disease attack, revenue from selling cassava, cassava selling price, industrial
demand awareness, getting extension services, need for training and farming group
membership. Smallholding farmers at Muheza district were more willing to pay compared
to Kwimba and lastly Sengerema respectively. It was recommended that community
based or commercial planting materials farms be established to ensure smallholding
farmers obtain clean quality improved planting materials affordably and timely. It was
recommended that a proper governance of the cassava value chain be put in place with
measures such as establishing a cassava governing board and policy framework such as a
Cassava Master Plan
Optimizing p and k for improving biological nitrogen fixation and productivity of bambara groundnut (v igna Subterranea ) in South-Eastern Tanzania
No full textA DissertationBambara groundnut (Vigna subterranea (L) Verde) is a pulse crop cultivated by
smallholder farmers in Tanzania, ranked the third most important legume in the SEZ after
pigeon pea (Cajanus cajan) and cowpea (Vigna unguiculata). Farmers in south-eastern
Tanzania grow Bambara groundnut primarily for food and sell part of the produce to
supplement income of their household. However, the productivity of Bambara groundnut
is below the potential yield (< 2 t ha -1 ), and is considered a threat to their livelihood.
Among the factors causing low yields of Bambara groundnut include insect pests and
disease incidences, poor agronomic practices and low soil fertility. Low soil fertility is
amplified by continual mining of nutrient elements from the soil and reduction of soil
organic matter content, through the removal and burning of crop residues and without
applying balanced nutrients. Balanced supply of plant nutrients is important in order to
improve and sustain yields of Bambara groundnut in South-Eastern Zone (SEZ). However,
the establishment of the technologies of soil fertility management is hindered by
inadequate information on soil characterization and classification of soils. These
agronomic experiments would lead to establish technology that would be transferred to
other areas of similar soil conditions for Bambara groundnut production, particularly in
Tanzania. Furthermore, all developed interventions concentrated on improving Bambara
groundnut varieties; plant spacing, morphology and diversity of the crop are known. The
information on soil nutrient status including phosphorus (P) and potassium (K) for SEZ is
not well known, and the required optimum rates are not yet established. Therefore, the
intention of this study was to determine the status of soil fertility and optimum rates of N,
P and K for Bambara groundnut production in the SEZ.
A standard survey was carried
out in the Bambara groundnut growing areas of SEZ, to establish representative
experimental sites on the basis of agro-ecological settings and soils. The morphology, genesis, physio-chemical properties and classification of soils based on two international
soil classification systems, namely USDA Keys to Soil Taxonomy and the World
Reference Base (WRB), were assessed. Three pedons were characterized, namely NNL-P1
at Nannala village in Tandahimba district, MKG-P1 at Mikangaula village and NWJ-P1 at
Nawaje village in Nanyumbu district. Disturbed and undisturbed soil samples from genetic
soil horizons were analyzed for physico-chemical properties. Soil nutrient status for
macro-nutrients (N, P, K, Ca, Mg and S) and micro-nutrients (Fe and Zn) were assessed
from 22 soil samples from Bambara groundnut growing areas of south-eastern Tanzania.
Field experiments were established on two pedons, namely NNL-P1 and NWJ-P1. The
experiments were used to establish optimum rates of P and K for N 2 fixation and yields of
Bambara groundnut in south-eastern Tanzania. The treatments for the field experiments
were varied rates and combinations of P (0, 20, 40, or 60 kg P ha -1 ), K (0, 40 or 80 kg K
ha -1 ) and N (0, 20 or 80 kg N ha -1 ), as sub-plots, in a split plot design replicated three
times. The main plots were two varieties of Bambara groundnut (local and improved). The
characterization results indicated that two pedons NNL-P1 and MKG-P1 were classified to
great group level using the USDA Keys to Soil Taxonomy as Dystrustepts and
Haplustepts, respectively, and these translated into Cambisols in the WRB for Soil
Resources. Pedon NWJ-P1 was classified as Argiustolls and translated into Phaeozems in
the WRB. Over 60% of 22 soil samples analyzed for nutrient status, the limiting nutrients
for productivity were N, P K, S, Mg and Zn, which were rated as being very low to low,
while Ca was rated as medium in >80% of the soils of the studied areas. It was concluded
that low nutrient status especially N, P, K, S, Mg and Zn, needs proper management to
improve soil fertility for Bambara groundnut production. Application of P increased N 2
fixation and Bambara groundnut yield significantly. Thus, use of P at the rates of 20 – 40
kg P ha -1 is deemed necessary for high yields in the study area