This study was conducted on prevalence of intestinal helminthes infection and their associated risk factors among school children from a rural and a semi urban setting in Lumame town, Northwest, Ethiopia. A cross-sectional parasitological study was conducted to determine the prevalence and associated risk factors of intestinal helminthes infection. A total of 402 students' stool samples were taken and processed with direct wet mount and formalin ether concentration techniques from December to January 2011/2012. A structured questionnaire was prepared to assess the association of intestinal helminthes infection with socio-demographic and socioeconomic variables. The data collected was analyzed using  2 test and logistic regression (p < 0.05 was considered as statistically significant). The overall prevalence rate for at least one intestinal helminthes infection was 54.5%. Of which Ascaris lumbricoides (32.6%) was the dominant followed by hookworm (12.2%); the others were minor cases. High rate infection (A. lumbricoides) was recorded among students who had dirty finger nails, large family, habit of eating undercooked vegetable, walking barefoot, and had no latrine than their respective counterpart. Such relatively high prevalence rate of helminthes infection in the study area could be used as a baseline for the concerned bodies to launch de-worming intervention.

Field trials were carried out at three locations in the cool-wet western and one location in the semiarid eastern ecozones of the Amhara State of Ethiopia to determine the effects of nitrogen fertilizer on pest infestation and yield losses caused by lepidopterous stemborers in maize and sorghum. Three N fertilizer levels, i.e. 60, 120 and 180 kg/ ha for maize, and 41, 64, and 87 kg/ha for sorghum, were compared with a zero N treatment. The dominant pest species were the noctuid Busseola fusca (Fuller) and the invasive crambid Chilo partellus (Swinhoe). Leaf N content was positively related to N fertilizer dosage. In general, pest density, parasitism, plant growth and borer damage variables increased with crop growth stage. On sorghum, in the cool-wet western Amhara, increasing levels of N fertilizer also tended to increase pest density, plant growth and damage variables. In the semiarid ecozone, parasitism by the exotic parasitoid Cotesia flavipes Cameron tended to increase with N level. In the cool-wet ecozone, sorghum yields increased by up to 74% because of fertilization; losses caused by stemborers decreased linearly with N dosage from 49% to 36%. In maize, because of low borer densities, there were no discernable trends for pest infestation and yield losses. In the cool-wet ecozone, sorghum yields were positively related to insecticide application and plant height, and negatively to damage variables such as tunnelling and peduncle damage. In semiarid eastern Amhara, the effects of fertilizer on pest, damage and yield were low on both crops because of the higher soil fertility. The results indicate that the profitability of nitrogen fertilizer as an integrated pest management tactic in the control of cereal stemborers depends, among others, on the severity of borer damage and the soil fertility status prevailing in an area. It is concluded that N fertilizer helps minimize the impact of borers on grain yields, especially on sorghum and in the cool-wet ecozone.

The biology of the pea aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae), on four legumes (faba bean, field pea, lentil and grass pea) was studied in a greenhouse during the 1999/2000 seasons. There was no significant difference in length of nymphal period and number of moults (instars) among the crop species tested. The aphids generally took 9 to 11 days to reach the adult stage with a maximum of 3 moults. Lifespan was significantly longer on lentils than on other crops. Significantly more aphids survived beyond 15 days on lentil than on other crops. Similarly, the reproductive and post-reproductive period and adult longevity were longer on lentil. The prereproductive period was significantly higher on field pea than on the other crops. The net reproductive rate (RJ was highest on lentil (103.56 females/female) and the intrinsic rate of increase (r) was highest on faba bean due to a short generation time (14.27 days). Generally, lifetime fecundity was higher on lentil (115.10/female) due to a higher daily reproduction raje (6.7 nymphs/female/day) on this crop. Nymphal production per aphid was strongly and positively correlated with lifespan, reproductive period and adult longevity but not of the nymphal period. Daily nymph production was significantly correlated with minimum temperature on lentil alone (F = 4.61, P < 0.05). Knowledge of the crop species and varieties susceptible to pea aphid is useful for identifying diets for the mass rearing of aphids for use in resistant variety selection and as diet for artificial natural enemy production. The present experiment indicates that lentil is suitable for both purposes. 171 172 M. WALEetal.lentille (F = 4,61, P < 0,05). La connaissance d'especes et varietes de plantes sensibles vis-a-vis du puceron du pois est utile lors de ['identification des medias pour 1'elevage en masse des pucerons utilises dans la selection pour la resistante varietale ou comme milieu pour la production artificielle des ennemis naturels. Cette experience indique que la lentille est mieux indiquee pour les deux finalites.Mots Cles: puceron du pois, Acyrlhosiplion pisum, biologie, etat nymphal, duree du cycle biologique, longevite, recondite, nourriture a base de legumineuses

Background. Malaria is a major mosquito-borne disease in Ethiopia, and it is one of the leading causes of morbidity and mortality. Plasmodium falciparum and P. vivax are the two malaria-causing parasitic species commonly known to cause human malaria in Ethiopia. To better manage and control vectors transmitting malaria parasites, the abundance, distribution, and updated annotated list of Anopheles species present in Ethiopia are very important. Methods. In order to compile a list of the species recorded in Ethiopia, 33 original research articles were collected. This work gives an updated list of Anopheles mosquito species in Ethiopia and their abundance, distribution, and composition. Results. According to this review, 110305 Anopheles mosquitoes were collected and 35 Anopheles species were recorded in different parts of Ethiopia. A. arabiensis was the most abundant when compared to other species, whereas A. maculipalpis and A. wilsonii were the least abundant species. The most abundant Anopheles species was recorded in central and the least abundant, from eastern Ethiopia. The second, third, and fourth abundant species were also collected from southern, northern, and western parts of Ethiopia.

Abstract. The distribution and relative importance of lepidopteran and coleopteran stem borers and their natural enemies on maize and sorghum were studied in cereal growing zones of the Amhara State of Ethiopia from 2003 to 2004. Sorghum is the major crop in semi-arid eastern and maize in the cool-wet western zones of the Amhara state. Four administrative zones, 10 districts and 88 localities in the semi-arid ecozone (SAE) and four zones, 19 districts and 71 localities in the cool-wet ecozone (CWE) were chosen for the study. In SAE, the species composition was 91% Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), 8% Busseola fusca (Fuller) (Lepidoptera: Noctuidae) and 1% Sesamia calamistis Hampson (Lepidoptera: Noctuidae). In the CWE, maize and sorghum are grown in different ecozones and thus B. fusca was the dominant species on sorghum, whereas 61% B. fusca and 39% S. calamistis were recorded on maize. Borer density generally increased with crop growth stage. C. partellus parasitism by C. fl avipes Cameron (Hymenoptera: Braconidae), which occurred only in SAE, varied among districts ranging from 5% to 39%. In the CWE, unidentifi ed nematodes parasitized medium-sized B. fusca larvae during the wet months. Population of native parasitoids was very low. The coleopteran borer, Rhynchaenus niger (Horn) (Coleoptera: Rhynchophoridae), attacked sorghum plants in both regions. Sorghum yields were negatively related to plant damage variables and positively to larval parasitism and plant growth variables. On maize, plant damage was too low to affect yields. Taylor's power law indicated aggregated distribution for C. partellus and B. fusca larvae and pupae combined. Dans les zones froides et humides, le maïs et le sorgho ne sont pas cultivés ensemble, mais dans différentes zones écologiques. De ce fait, B. fusca était l'espèce de lépidoptère foreur dominante sur sorgho, alors qu'elle ne représentait que 61% sur maïs où S. calamistis était aussi présent pour 39%. La densité de lépidoptères foreurs a augmenté généralement avec le stade de développement des plantes. Le taux de parasitisme de C. partellus par Cotesia fl avipes Cameron (Hymenoptera : Braconidae), qui est présent seulement dans les zones semi-arides, variait selon les districts de 5% à 39%. Dans les zones froides et humides, une espèce de nématode non identifi ée attaquait les larves de B. fusca de taille moyenne pendant les mois les plus humides. La population des parasitoïdes autochtones de cette zone était très faible. Le coléoptère foreur, Rhynchaenus niger (Horn) (Coleoptera : Rhynchophoridae), infestait le sorgho dans les deux types de régions. Le rendement en sorgho était négativement corrélé aux paramètres liés aux dommages de la plante et positivement au parasitisme larvaire et aux variables liées à la croissance de la plante. Sur maïs, les dommages de la plante étaient trop faibles pour en affecter son rendement. La loi de Taylor a indiqué une distribution d'agrégation pour les larves et les chrysalides de C. partellus et B. fusca.