Maize In Tanzania Research Articles

Agricultural input subsidies, extension services, and farm labour productivity nexus: Evidence from maize farmers in Tanzania

AbstractThis paper examines the effect of agricultural input subsidies (AIS) and agricultural extension services (AES) on farm labour productivity in plots planted with maize in Tanzania, using panel data from the National Panel Survey in Tanzania. To control for the endogeneity of the two programmes, a control function and instrumental variable approach is used to estimate the effects of AIS and AES on farm labour productivity. The results show that AIS and AES are significant in raising labour productivity in maize‐planted plots. Similarly, AIS and AES are also effective in increasing land productivity in these plots. Moreover, each programme has comparable effects on land productivity and farm labour productivity. These findings imply that public investments in AIS and AES are effective in raising farm productivity.

Towards food nutrition improvement: Assessment of Farmers’ knowledge, perceptions and access to provitamin A-rich Maize in Tanzania

Towards food nutrition improvement: Assessment of Farmers’ knowledge, perceptions and access to provitamin A-rich Maize in Tanzania

Soil-atmosphere exchange of nitrous oxide in two Tanzanian croplands: Effects of nitrogen and stover management

Cropland intensification is needed to meet the demand for food in sub-Saharan Africa (SSA). This process requires a dramatic increase in resource inputs, including fertilizer-nitrogen (N) and organic residues (e.g., stover), which alter the soil-atmosphere exchange of nitrous oxide (N2O). The dearth of N2O emission data for SSA croplands, however, limits our ability to define regional and global N2O flux and mitigation opportunities. In two soils planted with maize in Tanzania (Iringa, sandy Alfisols; Mbeya, clayey Andisols), we conducted year-round measurements for 2 consecutive years to quantify N2O emissions in response to increasing N rates and in combination with maize stover incorporation. Rainfall and the resulting soil moisture, rather than soil temperature, were important environmental drivers of N2O emissions in these fields. Applied N stimulated N2O fluxes across soil types but with different magnitudes—lower in Iringa because of the dominance of nitrification in N2O production and higher in Mbeya likely from promoted denitrification when the water-filled pore space was >47%. N2O emission increased exponentially or linearly with N rate, depending on the year. The direct N2O emission factors were well below the 1% of the IPCC Tier 1 method, ranging from 0.13% to 0.26% in Iringa and from 0.24% to 0.42% in Mbeya, for a N rate of 50–150 kg N ha−1 during the study. Compared with N application alone, stover plus N did not significantly alter maize yield, but did raise N2O emissions significantly (P ≤ 0.06). Consequently, stover incorporation markedly increased the emission factor (up to 0.46% in Iringa and 1.29% in Mbeya) as well as yield-scaled N2O emissions. Our results suggest that linear and exponential emission responses can occur in SSA croplands and challenge the promotion of combining stover with fertilizer-N as resource input management in this region.

Characterization and detection of maize-associated pteridovirus (MaPV), infecting maize (Zea mays) in the Arusha region of Tanzania

Maize lethal necrosis disease (MLND) is currently threatening maize production in a large area of East Africa. Synergistic infections of Maize chlorotic mottle virus (MCMV) and members of the Potyviridae family are known to elicit MLND. Metaviromics studies of plant viruses have allowed for the discovery of novel viral diversity, with a number of these viruses having recently been shown to co-occur with MCMV and Potyviruses. However, their contribution to the expression of disease symptoms still requires extensive research. In a survey for viruses associated with maize in Tanzania, 35 samples were sequenced using an RNA-tag-seq metaviromics approach. Bioinformatic analysis of assembled reads yielded two contigs (5.8 and 2.7 kbp) that shared sequence homology with RNA1 and RNA2 of the dsRNA Japanese holly fern mottle virus (JHFMoV) (genus: Pteridovirus) from a single sample collected in the Arusha region. RNA1 encodes for a polyprotein product containing putative viral methyltransferase, helicase and polymerase domains. RNA2 contains three open reading frames (ORFs), one of which encodes for a putative movement protein, while the remaining two encode for putative products with no known function. The tentative name Maize-associated pteridovirus (MaPV) has been proposed for the virus in this study.

English

Rice (Oryza sativa L.) is the second most important food crop after maize in Tanzania. It faces many challenges like diseases, pests and physical damages, which reduce the seed quality. This article identified microorganisms and the district where they occurred. 13 fungal species comprising of 11 pathogenic and 2 saprophytic fungi were detected and the incidence level varied among sample. Mvomero District showed the highest incidence recorded (64.5%) for sample collected from Hembeti and Dakawa/Msufini villages. In Kilombero, the fungal specie which detected highest incidence was Fusarium equiseti (31%) followed by Fusarium moniliforme (28.5%). Verticillium cinnabarinum and Curvularia inaequalis had the least incidence of 1 and 1%, respectively. The study recommends that before planting season, seeds should be tested to minimize spread of fungal species.   Key words: Pathogens, quality declared seed (QDS), farmer saved

Spatially-explicit effects of seed and fertilizer intensification for maize in Tanzania

Slower than desired growth in crop yields coupled with rising food demand present ongoing challenges for food security in Africa. Some countries, such as Tanzania, have signed the Malabo and Abuja Declarations, which aim to boost food security through increasing crop productivity. The more intensive use of seed and fertilizer presents one approach to raising crop productivity. Our simulation study examined the productivity and economic effects of planting different seed cultivars and increasing fertilizer application rates at multiple spatial scales for maize in Tanzania. We combined crop simulation modelling with household data on costs and prices to examine field-scale and market-scale profitability. To scale out our analysis from the field scale to the regional and national scale (market scale) we applied an economic surplus model. Simulation results suggest that modest changes in seed cultivars and fertilizer application rates can double productivity without having a negative effect on its stability. The profitability of applying extra fertilizer, calculated as its value-cost ratio, increased if improved seed cultivars replaced local seed cultivars. Rankings of district-scale profits differed from rankings of district scale yields, highlighting the importance of considering economic factors in assessments of input intensification. At the national scale, simulation results suggest the total benefit could be US$ 697 million over 5 years if there was a 39 percent adoption rate of planting improved seed and applying extra mineral fertilizer. Providing economic assessments of input intensification helps build evidence for progressing the Malabo and Abuja Declarations.

Forecasting Wholesale Prices of Maize in Tanzania Using Arima Model

Forecasting Wholesale Prices of Maize in Tanzania Using Arima Model

Potential of using host plant resistance, nitrogen and phosphorus fertilizers for reduction of Aspergillus flavus colonization and aflatoxin accumulation in maize in Tanzania

Aflatoxin contamination (AC) in maize, caused by the fungal pathogen Aspergillus flavus (Link), starts at pre-harvest stage. Hence, interventions that reduce entry and development of A. flavus in the field are required. Trials were carried out at Seatondale and Igeri, to evaluate the effects of nitrogen and phosphorus fertilizer combinations, hereafter referred to as fertilizers, on A. flavus and AC in maize kernels. The main treatments were four combinations of N and P fertilizers (60 or 120 kg Nha−1 with 15 or 30 kg Pha−1) and sub-treatments were of six popular maize hybrids. Plants at 50% silking were inoculated with the fungus through the silk channels. Grains from inoculated and control ears were analysed for AC using Enzyme Linked Immunosorbent Assay, and pathogen content quantified by Quantitative Polymerase Chain reaction. Higher AC (mean 6.51 μg kg−1) occurred at Seatondale than Igeri (mean 0.45 μg kg−1), probably due to low temperatures (8–23 °C) at Igeri. Fertilizers didn't cause significant differences in neither pathogen colonization nor AC at both sites. However, mean A. flavus accumulation, as measured by pathogen host DNA ratio, was thrice (0.16) as high in sub-optimal fertilizer conditions compared to optimal fertilizer rate (0.05). All hybrids were susceptible to A. flavus and AC, though a difference in AC was noted among the hybrids at both sites. PAN 691 showed the highest AC (14.68 μg kg−1), whereas UHS 5210 had the lowest AC (1.87 μg kg−1). The susceptibility varied among the hybrids and was mostly associated with ear droopiness, husk tightness, days to 50% silking, 50% pollen shed, Anthesis to silking interval, diseased ears, insect damaged ears, kernel texture, dry matter, grain filling, ear height, kernel ash content and kernel moisture content. At Seatondale, A. flavus accumulation was positively correlated with aflatoxin (r = 0.606), and both A. flavus accumulation and AC were positively correlated with diseased ears. Selection and growing of less susceptible varieties under optimal fertilizer regime offer ideal strategy for sustainable reduction of A. flavus and aflatoxin contamination in maize at pre-harvest.

Technology adoption and the multiple dimensions of food security: the case of maize in Tanzania

The paper analyses the impact of agricultural technologies on the four pillars of food security for maize farmers in Tanzania. Relying on both matching techniques and endogenous switching regression models, we used a nationally representative dataset collected over the period 2010/2011 to estimate the causal effects of using improved seeds and inorganic fertilizers on food availability, access, utilization, and stability. Our results show that the adoption of both technologies have positive and significant impacts on food availability while for access, utilization and stability we observe heterogeneity between improved seeds and inorganic fertilizers as well as across the food security pillars. The study supports the idea that the relationship between agricultural technologies and food security is a complex phenomenon, which cannot be limited to the use of welfare indexes as proxy for food security.

Big Constraints or Small Returns? Explaining Nonadoption of Hybrid Maize in Tanzania

AbstractNew technologies are often not widely adopted by farmers in Africa. Several adoption constraints have been discussed in the literature, including limited access to information. Using data from maize farmers in Tanzania, we challenge the hypothesis that limited information is an important constraint for hybrid seed adoption. While we find an adoption gap from lack of hybrid awareness, this gap is sizeable only in regions where productivity gains of hybrids are small. Hence, awareness of a new technology may be a function of expected returns. Other constraints related to assets and credit are not significant. We conclude that not adopting a technology is not always a sign of constraints but may also indicate low benefits from its use.

The Paradox of Agricultural Trade Liberalization in Bangladesh and Tanzania

This paper examines some of the contradictions and theoretical ambiguities of agricultural trade liberalizationon the welfare of smallholder farmers. Using production, consumption and price data for pre-and post-liberalization periods for two main agricultural crops from Bangladesh (rice) and Tanzania (maize) we critically analyse the correlation between domestic and international prices of rice in Bangladesh and maize in Tanzania to estimate impact of agricultural trade liberalization on price stability/volatility and food security to measure economic benefits of trade liberalization on smallholder farmers. Using coefficient of variation of the level of prices (CV) and corrected coefficient of variation (CCV) as measured by Huchet-Bourdon (2011) we found that the values of both CV and CCV for consumer price in the post-liberalisation were quite large suggesting greater volatility of consumer price of rice in Bangladesh and maize in Tanzania in the post-liberalization period. We conclude that price volatility diminishes the potential benefits of agricultural trade liberalization forsmallholder farmers who are net-deficit producers, net-deficit sellers and recommend supplementary policy interventions to achieve enhanced welfare from trade liberalization.

The Paradox of Agricultural Trade Liberalization in Bangladesh and Tanzania

This paper examines some of the contradictions and theoretical ambiguities of agricultural trade liberalizationon the welfare of smallholder farmers. Using production, consumption and price data for pre-and post-liberalization periods for two main agricultural crops from Bangladesh (rice) and Tanzania (maize) we critically analyse the correlation between domestic and international prices of rice in Bangladesh and maize in Tanzania to estimate impact of agricultural trade liberalization on price stability/volatility and food security to measure economic benefits of trade liberalization on smallholder farmers. Using coefficient of variation of the level of prices (CV) and corrected coefficient of variation (CCV) as measured by Huchet-Bourdon (2011) we found that the values of both CV and CCV for consumer price in the post-liberalisation were quite large suggesting greater volatility of consumer price of rice in Bangladesh and maize in Tanzania in the post-liberalization period. We conclude that price volatility diminishes the potential benefits of agricultural trade liberalization forsmallholder farmers who are net-deficit producers, net-deficit sellers and recommend supplementary policy interventions to achieve enhanced welfare from trade liberalization.

Technology Adoption and the Multiple Dimensions of Food Security: The Case of Maize In Tanzania

Technology Adoption and the Multiple Dimensions of Food Security: The Case of Maize In Tanzania

Exposure of infants to fumonisins in maize‐based complementary foods in rural Tanzania

Feeding children with maize may expose them to fumonisins (FBs). This study assessed FB exposure for infants consuming maize in Tanzania by modeling maize consumption data (kg/kg body weight (bw)/day) with previously collected total FB contamination (microg/kg) patterns for sorted and unsorted maize harvested in 2005 and 2006. Consumption was estimated by twice conducting a 24 h dietary recall for 254 infants. The exposure assessment was performed with the @RISK analysis software. Of the infants, 89% consumed maize from 2.37 to 158 g/person/day (mean; 43 g/person/day +/- 28). Based on the contamination for sorted maize; in 2005, the percentage of infants with FB exposures above the provisional maximum tolerable daily intake (PMTDI) of 2 microg/kg (bw) (26% (95% confidence interval (CI); 23-30)) was significantly higher than the level of 3% (90% CI; 2-12) in 2006. Pooling the datasets for sorted maize from the two seasons resulted in a seemingly more representative risk (10% (95% CI; 6-17)) of exceeding the PMTDI. However, infants who might have consumed unsorted maize would still be at a significantly higher risk (24% (95% CI; 15-34)) of exceeding the PMTDI. Sorting and other good maize management practices should be advocated to farmers in order to minimize FB exposure in rural areas.

Human exposure to fumonisins from home grown maize in Tanzania

Fumonisins contaminate maize worldwide resulting in unacceptable fumonisin exposures in people relying on maize as staple food. This study determined fumonisins B1 (FB1) and B2 (FB2) in maize from 120 rural households: 30 from each of four main maize producing regions of Tabora, Ruvuma, Iringa and Kilimanjaro in Tanzania in order to estimate total fumonisin (FB1 + FB2) exposures to adult individuals in the households. The average daily per capita maize consumption of 771 g, recommended by the Tanzania Food and Nutrition Centre (TFNC) for an adult relying on it as a main meal, and also average daily per capita maize consumptions of 129, 308 and 356 g documented for Tanzania, were used in the exposure estimation. The fumonisins were determined by HPLC using fluorescence detection. Total fumonisins exposure (µg/kg body weight (bw)/day) was determined by multiplying average daily per capita maize consumption (kg) by fumonisin level in maize (µg/kg) from a given household and then dividing by an average bw of an adult of 60 kg. Of the 120 samples, 52% were contaminated with fumonisins at levels of up to 11,048 µg/kg (median; 363 µg/kg). Based on the recommended maize consumption of 771 g/person/day, fumonisin exposures to adult individuals in 38% of the households would exceed the provisional maximum tolerable daily intake (PMTDI) of 2 µg/kg bw, recommended by the Joint FAO/WHO Expert Committee on Food Additives. At the least documented maize consumption of 129 g/person/day, fumonisin exposures in 16% of the households were still above the PMTDI. Reduction of the maize consumption level to 40 g/person/day is an impractical, and reduction of the maximum contamination level to 155 µg/kg is a possibly practical, option for effective minimisation of fumonisin exposures in these communities. A relatively larger study is needed in order to generate comprehensive data for the formulation of appropriate strategies to minimise fumonisin exposures in Tanzania.

Cross-Pollinated Crop Variety Adoption Studies and Seed Recycling: The Case of Maize in Tanzania

A survey of 126 maize farmers was conducted in northern Tanzania with the objective of examining adoption of cross-pollinated seeds among farmers who recycle improved seeds. In this study, an improved variety is defined as any variety that has been bred using formal plant breeding methods. Formally bred cultivars that have been recycled but still maintain some of their characteristic attributes were also categorized as “improved.” About 91% of sample maize farmers used improved seeds. Heckman's two-step procedure was used to examine the factors that affect the probability to adopt and the intensity of adoption of improved maize seed and chemical fertilizer use. Most factors included in the model did not have a statistically significant impact on the adoption of improved maize varieties. The determinants of adoption did not have a significant impact probably due to the high rate of adoption of improved maize seed (91%). Researchers conducting studies in areas where seed recycling is common need to use a more restrictive definition of “improved seeds” than the one used in this study. In the case of studies examining factors influencing intensity of adoption, researchers need to determine the intensity of adoption by using scaling factors that are based on loss of genetic potential (yield) due to seed recycling. Such scaling factors may be determined empirically since they vary from one maize variety to another. About 64% of the moderate rainfall zone (800 – 1200 mm per year) respondents used chemical fertilizer, as compared to 44% in the low rainfall zone (500 - 800 mm per year). The level of fertilizer applied was well below recommended rates, hence the need to research on and promote extension efforts in organic fertilizers that will complement the expensive chemical fertilizers. Eastern Africa Journal of Rural Development (2001) 17, 25-34