Food Security Incidences Based on Monetary and Caloric Poverty Lines in Mbeya and Makete Districts, Tanzania

In Tanzania, a food monetary poverty line of TZS[1] 10,219 per adult equivalent for 28 days in 2007 prices and a caloric poverty line of 2,200 kcal per adult equivalent per day are used. However, it is not known where their uses give similar incidences of food security. Generation of empirical information on this was worthwhile to inform choices of which of the lines should be more preferable. This study sought to determine food security based on monetary and caloric poverty lines in Mbeya and Makete Districts. The specific objectives of the study were to: (1) Determine food security based on the national monetary poverty line, (2) Determine food security based on caloric food poverty line, and (3) Compare food security incidences based on the two poverty lines. Multistage sampling was used to select 233 households. The research was a cross-sectional one and was conducted through structured interviews using a questionnaire, focus group discussions and key informant interviews. Using the national food monetary and calorific food poverty lines, it was found that 82.8% and 79.0% of the 233 sampled households were food secure in Mbeya and Makete respectively. Monetary and caloric food poverty lines gave almost similar results of food security incidences, albeit the monetary food poverty line gives slightly higher food security incidences. It is concluded that the two poverty lines give almost similar food security incidences and have good potential to give reasonable results of food security status. It is recommended that the government and other stakeholders dealing with food security should use both food poverty lines almost equally since they give almost the same results. Keywords: Food security, monetary, calorific, poverty line, Southern Highlands, Tanzania [1] USD 1 equals about TZS 1784 in November 201

Impact of Round Potato Production on Household Food Security in the Southern Highlands of Tanzania

Smallholder farmers in Mbeya Rural and Makete Districts recognise food insecurity as a problem affecting them. They also recognise the potential of round potato as a crop contributing to household food security. However, the extent to which the crop contributes to food security had not been quantified. The purpose of this study was to determine the contribution of potato production to household food security in Mbeya and Makete Districts in the Southern Highlands of Tanzania. The specific objectives of the paper are to: (1) analyse round potato production and other crops grown in the study area, (2) assess food security in terms of dietary energy consumed (DEC) and (3) determine the impact of round potato production on food security. Multistage sampling was used to select 233 potato farmers. The research was a cross-sectional one and was conducted mainly through structured interviews using a questionnaire, which was supplemented with focus group discussions and key informant interviews. The dependent variable, food security in terms of dietary energy consumed per adult equivalent per day, was regressed on seven independent variables to find the impact of each of them on the dependent variable. The variables were household size, age of household head, DEC from potato, income from potato, income from other crops, years of schooling of household head and income from non-agricultural activities. The results showed that there were positive significant impacts of DEC from potato, household size and income from non-agricultural activities on food security. It is recommended that the government should support farmers in terms of availability of inputs, training on improved technologies and support research on round potato. Keywords: Round potato, Food security, Southern Highlands, Tanzani

Contribution of Round Potato Production to Household Income in Mbeya and Makete Districts, Tanzania

In Tanzania, agriculture remains the largest sector of the economy, and hence its performance has substantial impacts on income and poverty.  Round potatoes are grown in all continents under various climatic conditions. Smallholder farmers in Mbeya Rural and Makete Districts in Tanzania recognise the potential of round potatoes as a crop contributing significantly to household income and food security. The purpose of this study was to determine the contribution of potato production to household income in Mbeya and Makete Districts in the southern highlands of Tanzania. The specific objectives of the research were to: (1) analyse round potato production and other crops grown in the study area, (2) assess household income from round potato and from other sources in the study area and (3) determine the impact of round potato production on household income. A cross-sectional research involving 233 potato farmers was conducted in March 2012 through structured interviews using a questionnaire, focus group discussions and key informant interviews. The dependent variable, household income, was regressed on eight independent variables to find the impact of each of them on the dependent variable. The results showed that there was high positive significant impact of income from round potato per adjusted adult equivalent unit (AAEU) on household income (p < 0.001). It is concluded that round potatoes are more profitable than other major crops grown in the study area. Moreover, if given due attention and care, round potatoes can contribute greatly to household income. It is recommended that the government should support farmers in terms of availability of inputs, training on improved agricultural technologies and support for research on round potatoes so that they can help increase household income. Keywords: Round potato, household income, Southern Highlands, Tanzani

An Economic Comparison of Biological and Conventional Control Strategies for Insect Pests in Cashew and Mango Plantations in Tanzania

This study was undertaken to compare alternative methods of pest control for insect pests in order to determine which methods has the highest efficacy against insect pests and the least detrimental side effects, while maintaining production and profits. The analysis was based on the experimental trials for three treatments: weaver ants, chemical insecticides and control. Data on yields, quantities and prices of inputs and output were collected and analyzed using inferential statistics (t-test), partial budgetary technique and marginal analysis involving dominance analysis. The results of partial budget analysis shows that a change from chemical insecticides treatment to weaver ants returned net benefits greater than zero by Tsh. 692 923 and Tsh.1019665 in cashew and mango plantations respectively. Similarly, positive net benefits was obtained when growers change from control to weaver ants treatment by Tsh. 504 989 and Tsh. 891 297 in cashew and mango plantations. The dominance and MRRanalyses shows that if cashew and mango growers change from conventional agricultural practices to weaver ants, they would earn MRR of 1621% which is above minimum acceptable rate of return (MARR) of 100%. The t-test analyses show that weaver ant treatment is superior over conventional agricultural practices. The study concludes that weaver ant treatment was economically feasible and financially undertaking. Further field experimental trials will be repeated in the next two growing seasons to confirm results obtained in 2012. Key words: Conventional, weaver ants, partial budgeting, yield, cashew and mang

The use of light to enhance weaver ant Oecophylla longinoda Latreille (Hymenoptera: Formicidae) queen catches

Production of live weaver ant (Oecophylla longinoda and O. smaragdina) colonies is being developed as the ants provide several ecosystem services in agriculture and as they are used in education and research laboratories. Founding queens needed for colony production can be caught in artificial nests made of live leaves that are curled on trees. In this study we investigated if the catch rate of O. longinoda queens in artificial nests could be improved by attracting queens to trees with a light source (electric torches). We compared catch rates of 50 artificial nests on each of eight citrus trees, four of them with light and four without light. During two mating seasons covering 9 mating flights we caught a total of 178 queens. However, 3.8 times more queens were caught in the trees with light compared to trees without light. We conclude that queen catches can be highly improved by combining artificial nests with an attracting light source

Mating Behavior of the African Weaver Ant, Oecophylla longinoda(Latreille) (Hymenoptera: Formicidae)

Mating in most species of ants occurs during nuptial flights. In the African weaver ant, Oecophylla longinoda Latreille, mating has previously been hypothesized to take place within the nest before the nuptial flight. However, several researchers disagree with this supposition particularly with reference to the closely related species Oecopylla smaragdina (Fabricius) whose mating occur during nuptial flights. Understanding the mating strategy of O. longinoda is of importance for its successful application in biological control programs. We conducted field and screen house experiments during two mating seasons to determine whether the mating occur prior to the dispersal flight. We examined winged O. longinoda queens on the nest surface before taking flight, immediately after leaving the nest, up to twelve hours (12h) after leaving the nest and after settling naturally following the dispersal flights. Mating in captivity between different number of males and queens were also assessed. Only eggs produced by queens (N=65) collected after their natural settling hatched into larvae. No eggs hatched from any of the 527 winged queens that were collected prior to their dispersal flights and no mating attempts in captivity lead to viable offspring. Findings from the current study suggest that mating of O. longinoda queens take place during a nuptial flight and does not take place within the nest, as previously suggested

The search rate of the African weaver ant in cashew

Oecophylla longinoda is a species of eusocial colony living ants that prey upon other insects to feed their larva. Many of these insects are considered pests. An ecosystem model of the interactions between an O. longinoda colony and its potential prey is under construction by the team behind this article, and it is unknown which functional response equations are useful for eusocial insect colonies. We investigated the search rate of O. longinoda using artificial feeding experiments in a Tanzanian cashew (Anacardium occidentale L.) orchard to determine the search efficiency of the ants, and to assess which functional response equation can be used for eusocial insects. Artificial feeding experiments consisted of providing each of ten colonies 50 pieces of sardine (175 mg dry weight in average) in cashew trees at time 0 and counting the remaining food items at four intervals of 45 minutes during a seven day period. The equations of Gutierrez-Baumgärtner, Lotka-Volterra, and Nicholson-Bailey were assessed and the Nicholson-Bailey equation was found to be most suitable. The Gutierrez-Baumgärtner equation is useful if the demand for storage can be assessed. A large variation in search rates was found between the observed colonies and this problem is discussed in relation to Oecophylla sp. efficacy as a biological control agent

A review of the current knowledge on Zeugodacus cucurbitae (Coquillett) (Diptera, Tephritidae) in Africa, with a list of species included in Zeugodacus

This paper reviews all available information regarding the occurrence and biology of the melon fly, Zeugodacus cucurbitae (Coquillett), in the Afrotropical Region, including data on invasion history, distribution patterns, population genetics, host range, and interspecific competition. Although limited intraspecific variability has been observed within the region regarding the above mentioned aspects, there seems to be no indication that Z. cucurbitae represents a species complex. A checklist of all of the species included in Zeugodacus as recently proposed by Virgilio et al. (2015) is provided. (Résumé d'auteur

Population structure and cryptic genetic variation in the mango fruit fly, Ceratitis cosyra (Diptera, Tephritidae)

The fruit fly Ceratitis cosyra is an important agricultural pest negatively affecting the mango crop production throughout Africa and also feeding on a variety of other wild and cultivated hosts. The occurrence of deeply divergent haplotypes, as well as extensive morphological variability, previously suggested possible cryptic speciation within C. cosyra. Here we provide the first large-scale characterisation of the population structure of C. cosyra with the main objective of verifying cryptic genetic variation. A total of 348 specimens from 13 populations were genotyped at 16 polymorphic microsatellite loci. Hardy-Weinberg equilibrium (HWE) deviations were observed in 40.4% of locus-population combinations and suggested the occurrence of genetic substructuring within populations. Discriminant Analysis of Principal Components (DAPC) showed genetic divergence between the vast majority of vouchers from Burundi and Tanzania (plus a few outliers from other African countries) and all other specimens sampled. Individual Bayesian assignments confirmed the existence of two main genotypic groups also occurring in sympatry. These data provided further support to the hypothesis that C. cosyra might include cryptic species. However, additional integrative taxonomy, possibly combining morphological, ecological and physiological approaches, is required to provide the necessary experimental support to this model. (Résumé d'auteur