Genetic structuring among populations of the great egret,Ardea alba egretta,in major Brazilian wetlands

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Vorratsschädllche Insekten in Saudi-Arabien

A survey of insect pests of stored products in three main regions of Saudi Arabia was carried out during two successive years, 1978 und 1979. Randomized samples of different commodities were collected for inspection from 13 localities four times a year. Thirty six species of insect pests belonging to 12 families and 4 orders in addition to 2 hymenopterous parasites were recorded.     

Studies with permethrin against bodylice in Egypt

Approximately 350 people, the inhabitants of two villages in the Fayum district of Egypt, were individually dusted with 50 g of powder containing 2.5 or 5.0 g permethrin kg^?1. The inhabitants of a third village were left untreated as a control. Before treatment, approximately two-thirds of the population of all three villages were infested with bodylice. Fourteen days after treatment, the permethrin dust at the lower strength reduced the infestation by 98.8% and at the higher strength by 100%. The dust containing 5 g permethrin kg^?1 maintained a high level of residual control (80.5%) for at least 91 days. The other gave a lower level of control at this time. Urine samples, taken from subjects in each of the treated villages before and after dusting, were analysed for permethrin metabolites. Results indicated that the maximum amount of permethrin absorbed, orally, through the skin, or by inhalation, was 39 μg kg^?1 body weight, 24 h after treatment. No residue was found 30 days and 60 days after treatment. It was concluded that there was a very substantial safety margin when permethrin dusts were used on man for bodylice control.     

A field trial with permethrin against bodylice,pediculm humanus humanus in Egypt, 1976

Populations of bodylice, Pediculus humanus humanus L., in Egypt have become resistant to DDT and BHC, but not to malathion. A single dust application of permethrin (1 % a.i.; cis: trans-ratio 25:75) rendered 98.9% of the treated population louse-free. Thirty-seven days after dusting 91.3% and at the end of the 98-day observation period 64.6% of the population were free of infestation; during the same period the proportion of infested individuals rose by 12.3% in a similar untreated village. Permethrin is ovicidal against bodylice, affects the population of the human flea, PulexirritansL., and ishighly effective against the rat flea, Xenopsyllacheopis(Rothsch.).     

Farmer participation in barley breeding in Syria, Morocco and Tunisia

The paper describes experiments on farmer participation in plant breeding conducted in three countries (Morocco, Syria and Tunisia) on barley, which is the predominant annual rainfed crop in the most marginal areas of these countries. Trials with different types and number of breeding material were planted both on research stations and in farmers' fields. Selection was done by professional breeders and farmers and data were gathered on breeders' and farmers' selection criteria and selection efficiency. The trials reflected the situation of the crop in the three countries, with high yields on station, low yields in some of the most marginal farmers' fields, and poor correlations between research stations and farmers' fields, as well as between farmers' fields. Grain yield was by far the most commonly used selection criterion by the farmers. However, farmers also made a widespread use of selection criteria not normally used by breeders such as grain filling and straw yield, as well as other characteristics of the straw (color) and of the leaves because of the importance of the crop as source of animal feed. A major difference between the selection criteria used by breeders and farmers was disease resistance, almost entirely neglected by the latter. Farmer selection was effective in identifying some of the highest yielding lines in the farmers' own fields and also in those cases where they performed selection on station. The coincidence between entries selected by the breeder and the farmers was high in Morocco but very low in Syria and Tunisia. There were substantial differences between the lines selected by the breeders on station and those selected by farmers in their fields. In Syria, decentralized-participatory selection was significantly more efficient in identifying the highest yielding entries in farmers' fields than any other selection strategy. This work demonstrates that it is possible to organize a plant breeding program so that farmers become major actors in the selection of new cultivars. This revised version was published online in August 2006 with corrections to the Cover Date.