30 research outputs found
Sweeping the house clean : burrow architecture and seasonal digging activity in the East African root rat from Tanzania
We investigated changes in burrow architecture and fractal dimension across
seasons and between the sexes in the solitary East African root rat Tachyoryctes
splendens over an entire calendar year. The basic burrow system comprised a main
tunnel reticulating into foraging tunnels, a nest consisting of food store chamber,
latrine and sleeping area, and a bolt hole. Main tunnel length was strongly affected
by sex, and contrary to expectations, it was longer for females than for males
(during both the dry and the wet seasons). The number and the length of foraging
tunnels were affected by both sex and season, with females’ burrows having more
foraging tunnels than males in both the dry and the wet seasons. Females also had
burrows with higher fractal dimension than males, while fractal dimension
increased with burrow length for both sexes. We suggest that unlike the solitary
bathyergid mole-rats, male T. splendens do not construct larger burrows than
females in the search for mates, but rather females have larger burrows with more
foraging tunnels resulting from the increased need for provisioning of their young.University of Dar es Salaam (UDSM) World Bank Fund (C1B1 of the University of Dar as Salaam, Tanzania. NCB acknowledges funding from the South African DST/NRF SARChI Chair for Mammal Behavioural Ecology and Physiology,University of Pretoria.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1469-79982015-08-31hb201
Influence of resistance of kernels of sorghum cultivars on the biology of Rhizopertha dominica (Fab)
Available from British Library Document Supply Centre-DSC:DX189452 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
Paraconcinnum leirsi n.sp. (Trematoda: Dicrocoeliidae) from rodents in Tanzania and its phylogenetic position within the dicrocoeliids
The trematode Paraconcinnum leirsi n.sp. (Dicrocoeliidae) is described from two rodent species, the African gerbil, Gerbilliscus vicinus, and the spiny mouse, Acomys spinosissimus, from Tanzania. It differs from the description of P. hylomisci found in the Stella wood mouse, Hylomyscus stella, in the Democratic Republic of Congo. Molecular studies were performed by sequencing the near complete 18S rDNA gene of the fluke to assess its phylogenetic position within the Dicrocoeliidae. The resulting estimate of evolutionary divergence between the fluke and other dicrocoeliids was 1.60 ± 0.22% base differences per site. The phylogenetic analysis shows that the fluke is a new species within Dicrocoeliidae falling in a cluster with the genera Corrigia, Lyperosomum, Concinnum and Eurytrema although phylogenetic relationships among these genera are not well resolved. This is the first dicrocoeliid reported from rodents in eastern Africa.Key words: Acomys, Dicrocoeliidae, Gerbilliscus, Paraconcinnum, 18S rDNA gene
Host range and distribution of fruit-infesting pestiferous fruit flies (Diptera, Tephritidae) in selected areas of Central Tanzania
Bulletin of Entomological Research 2009; 99:629-641The host range of major fruit fly pests in Central Tanzania was evaluated from
October 2004 to October 2006. Samples of 48 potential hosts were collected and
incubated for fruit fly emergence. Bactrocera invadens was the dominant species in
incidence expressed as the ratio of infested to total number samples collected, as
well as infestation rate, expressed as number of flies emerging per unit weight.
Eight new host fruits are reported. Infestation by native pests, such as Ceratitis
capitata and C. cosyra, was minor compared to B. invadens. Ceratitis rosa was the
dominant species in temperate fruits, and Cucurbitaceae were mainly infested by
Bactrocera cucurbitae, a specialized cucurbit feeder. Among commercial fruits, high
infestation incidences were observed in mango and guava, but they decreased
throughout the fruiting season. Low infestation rates were observed in all Citrus
species and in avocado, indicating these fruits as poor hosts for the studied fruit fly
pests in this region. Widespread availability and abundance of fruit species
studied here ensures year-round breeding of B. invadens. Seasonal infestation dif-
fers, with mango being the most important host in October to January, while guava
being important from February to August. Tropical almond showed very high
incidence and infestation rate for B. invadens and might act as an important
reservoir host, bridging the fruiting seasons of mango and guava. Soursop acts as
an important host for C. cosyra after the mango season. Ceratitis capitata is a pest of
minor importance of the commercial fruits studied in this regio
Temporal variations in the abundance of three important insect pests of coffee in Kilimanjaro Region, Tanzania
Temporal variation in abundance of white coffee stem borer (WCSB), antestia bug and coffee berry borer (CBB) were investigated between September 2007 and August 2008 at medium altitude (1200-1600 m.a.s.l) and high altitude (1600-2100 m.a.s.l) areas in Kilimanjaro region. A multistage random sampling method was used to select farms and trees for sampling in the two locations making a total of 810 trees. Insects were counted every month to establish the population size. High populations of antestia bugs and CBB were recorded during the short and long rains, during flowering and fruit development. WCSB increased gradually during short and long rains. Populations of WCSB were high at high altitude compared to medium altitude and occurrence of CBB at medium altitude was observed where it was not common in the past. Since the population size of WCSB was high in all locations and it is the most damaging insect pest, it is recommended that more attention should be focused on management of this pest
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