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

Domestic Cat (Felis silvestris catus) Urine Odour as a Potential Rodent Management Strategy

The aim of this study was to investigate the effects of cat urine odour extract on rodent pest species to reduce crop losses. Cat urine from the captured cats was drawn using cat catcher. Urinary catheter was inserted into the urethra up to the urinary bladder and a syringe attached to the urinary catheter was used to draw urine which was stored in universal bottles at a temperature below -20ºC. The stored cat urine was directly bound to the maize starch by slowly mixing the urine with the starch until dough was formed which was then granulated. The granules were dried at room temperature and packed in a tight closed jar. Mastomys natalensis of 25 – 40 g were used in this study. Wild captured individuals were acclimatized in a room for 7 days prior to experiment by providing them with food and water. The effect of cat urine odours on rodent pest species was studied in a single box. Camera traps were set at the top of each room in order to monitor rodents’ activities. Our Findings suggests that cat urine odour has a potential to repel rodent pest species whereas female cat urine was more effective than male cat urine. However, more investigations are needed to evaluate its effectiveness under field conditions

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

Incidence and host range of the melon fruit fly Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) in Central Tanzania

International Journal of Pest Management, 2010; 56(3):265-273The incidence and host range of the melon fruit fly, Bactrocera cucurbitae, was studied in the Morogoro Region of Central Tanzania between October 2004 and October 2006. Occurrence was limited to low to medium altitude locations. Populations reached a peak in the dry season, between July and September. Host plants belonged mostly to the Cucurbitaceae family, with non-cucurbit hosts being infested occasionally and at low infestation rate. Highly preferred cucurbit hosts were cucumber (Cucumis sativus), melon (Cucumis melo) and watermelon (Citrullus lanatus), while Momordica cf trifoliata was the most important wild host. Bactrocera cucurbitae appeared to dominate most indigenous cucurbit infesters, with the exception of Dacus ciliatus which was still dominant in some cucurbitaceous spp

Incidence and host range of the melon fruit fly Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) in Central Tanzania

International Journal of Pest Management, 2010; 56(3):265-273The incidence and host range of the melon fruit fly, Bactrocera cucurbitae, was studied in the Morogoro Region of Central Tanzania between October 2004 and October 2006. Occurrence was limited to low to medium altitude locations. Populations reached a peak in the dry season, between July and September. Host plants belonged mostly to the Cucurbitaceae family, with non-cucurbit hosts being infested occasionally and at low infestation rate. Highly preferred cucurbit hosts were cucumber (Cucumis sativus), melon (Cucumis melo) and watermelon (Citrullus lanatus), while Momordica cf trifoliata was the most important wild host. Bactrocera cucurbitae appeared to dominate most indigenous cucurbit infesters, with the exception of Dacus ciliatus which was still dominant in some cucurbitaceous spp