Ex-ante Economic Impact Assessment of Green manure Technology in Maize Production Systems in Tanzania

In maize-based farming systems, intercropping of maize with green manure have been increasingly been one of the strategies to revive the declining maize production caused by increasing pests’ infestations and low soil fertility. This study analyzed the potential impacts of adoption of green manure technology on yield, cost, and profitability of maize production in the Eastern Zone of Tanzania. To assess the income and costs effects of maize production using green manure, a farm level budget was constructed from primary and secondary sets of data and information using a with-and-without framework of analysis. A partial budget was constructed to determine the incremental benefits from costs of adopting the green manure technology in managing noxious weeds such as Striga. Results showed that the adoption of green manure technology has a high potential to increase marketable yield, reduce costs and increase net profits. The partial budget analysis showed that green manure would give a net incremental benefit of Tsh. 478 654/acre compared to the chemical fertilizers used by farmers. These additional benefits were realized from increased marketable yields and savings from reduced chemical fertilizers and labour costs. Future research should strive to further develop and strategize dissemination channels to reach more of the smallholder population to increase their knowledge base on the alternative values of green manures. Keywords: Green manure, ex-ante impact assessment, investment in technology, partial budgetin

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

Ecological niche and potential geographic distribution of the invasive fruit fly *Bactrocera invadens* (Diptera, Tephritidae)

Two correlative approaches to the challenge of ecological niche modeling (genetic algorithm, maximum entropy) were used to estimate the potential global distribution of the invasive fruit fly, Bactrocera invadens, based on associations between known occurrence records and a set of environmental predictor variables. The two models yielded similar estimates, largely corresponding to Equatorial climate classes with high levels of precipitation. The maximum entropy approach was somewhat more conservative in its evaluation of suitability, depending on thresholds for presence/absence that are selected, largely excluding areas with distinct dry seasons; the genetic algorithm models, in contrast, indicate that climate class as partly suitable. Predictive tests based on independent distributional data indicate that model predictions are quite robust. Field observations in Benin and Tanzania confirm relationships between seasonal occurrences of this species and humidity and temperature

Effect of Mango weevil (Coleoptera: Curculionidae) damage on Mango seed viability in Tanzania

Research articleStudies were conducted at the horticulture unit of Sokoine University of Agriculture, Morogoro, Tanzania, to assess the incidence and effect of mango weevil, Cryptorhynchus mangiferae (F.) (Coleoptera: Curculionidae), infestation on mango, Mangifera indica L., seed viability. Three polyembryo mango cultivars (ÔSindano nyeusiÕ, ÔSindano nyeupeÕ, and ÔDodoÕ) as well as three monoembryo mango cultivars (ÔEx-horticultureÕ, ÔTangoÕ, and ÔBongwaÕ) were collected and examined for the presence ofC. mangiferae. The effect of seed damage on viability was assessed for both naturally and artiÞcially damaged seeds. However, for artiÞcially damaged seeds, the viability was assessed by cutting away 0, 25, 50, or 75% of the cotyledon before planting. In this experiment, only monoembryo mango cultivars were used. All the examined cultivars were infested by C. mangiferae, although at varying levels. Polyembryo mango cultivars were relatively more infested than monoembryo cultivars. Bongwa and Tango were least infested, whereas Sindano nyeusi recorded the highest C. mangiferae incidence. Germination rates of damaged seeds of polyembryonic cultivars differed signiÞcantly from the uninfested control, except for Sindano nyeusi. There were no signiÞcant differencesin germination percentage among the three monoembryo cultivars, and all the cultivars differed signiÞcantly from the uninfested control. The germination rates of seeds with 25% of their cotyledons removed did not differ signiÞcantly from the undamaged seeds, indicating that monoembryo cultivar seeds can withstand up to 25% damage and germinate successfully.Government of Tanzania through Ministry of Higher Education, Science and Technolog

Seasonality and host utilization of the invasive fruit fly, Bactrocera invadens (Dipt., Tephritidae) in central Tanzania

The temporal occurrence of the invasive and economically important pest fruit fly, Bactrocera invadens was studied in three agro-ecological areas of Morogoro Region, central Tanzania, during 2004–2005. Weekly and monthly trappings were carried out with methyl eugenol, protein bait and synthetic food attractant. Bactrocera invadens was permanently present at low and mid-altitudes (380–520 m a.s.l.) with peak periods coinciding with the fruiting season of mango (Mangifera indica) and guava (Psidium guajava). At high altitude (1650 m a.s.l.) its incidence was only temporal and apparently the result of dispersal from lower altitudes after the mango fruiting season. Rearing results showed mango, loquat (Eriobotrya japonica), guava and grapefruit (Citrus · paradisi) to be the favoured commercial host fruits. Other Citrus species, cucurbits, papaya (Carica papaya) and avocado (Persea americana) were less favoured

Seasonality and host utilization of the invasive fruit fly, Bactrocera invadens (Dipt., Tephritidae) in central Tanzania

The temporal occurrence of the invasive and economically important pest fruit fly, Bactrocera invadens was studied in three agro-ecological areas of Morogoro Region, central Tanzania, during 2004–2005. Weekly and monthly trappings were carried out with methyl eugenol, protein bait and synthetic food attractant. Bactrocera invadens was permanently present at low and mid-altitudes (380–520 m a.s.l.) with peak periods coinciding with the fruiting season of mango (Mangifera indica) and guava (Psidium guajava). At high altitude (1650 m a.s.l.) its incidence was only temporal and apparently the result of dispersal from lower altitudes after the mango fruiting season. Rearing results showed mango, loquat (Eriobotrya japonica), guava and grapefruit (Citrus · paradisi) to be the favoured commercial host fruits. Other Citrus species, cucurbits, papaya (Carica papaya) and avocado (Persea americana) were less favoured

Women’s prospects to adopt enhanced freshness formulation (EFF) technologies for banana in Morogoro rural district, Tanzania

The Journal of the Faculty of Food and Agriculture Volume 95 Special Issue 1This paper draws lessons from a study based on forecasts rather than actual results. The study was conducted to identify factors that could potentially affect women’s decisions to adopt enhanced freshness formulation (EFF) technologies among banana growers in Morogoro, Tanzania. The study tested whether men and women were equally likely to adopt EFF technologies. The authors also explored whether women who are willing and able to influence adoption decisions and women who are willing but unable to influence adoption decisions face similar adoption challenges. The results from logit model suggest that the adoption prospect is lower among female adopters than male adopters (p < .05). The study predicted a higher probability of female growers to be willing and able to influence adoption decisions among younger female growers compared to those over 35 years old (p < .1) although the overall impact on the adoption rate was low, owing to limited participation of young farmers (11 %) in banana production. The findings reveal less willingness and ability to adopt the technologies among female growers who perceived EFF applications as labour-insensitive technologies (p < .05). Likewise, the study identified higher willingness and ability to influence the adoption among growers whose bananas were not about to be harvested (p < .05). The authors recommend continued efforts to address a priori challenges that can potentially undermine adoption with easy-to-use preparation and application methods, and by targeting growers whose fruits are at early stages of maturation. Future studies could focus on the potential impacts of specific types of EFF technologies on the adoption prospect