Drosophila Melanogaster Laboratory Rearing

drosophila Melanogaster Laboratory RearingAbstractDrosophila melanogaster Linnaeus was reared for single generation in the laboratory on a simple diet of 13gm yeast, 250gm milk, 20gm cellulose waver and 1L water.Keywords Drosophila melanogaster, laboratory rearing, maturemental faces, artificial dietIntroductionDrosophila melanogasteris commonly known as fruit rainfly since its always found pricey unripe and rotted fruit. The fly inspired its genus name from the Latin word means dew loving. This genus could b easily identified by presence of black attribute hairs over their compound eye. This smallish fly has been paid attention since early 90th in many scientific investigations concerning behavioral and genetic studies. Thomas unravel Morgan was the first and outstanding biologist studyingDrosophilaearly in the 1900s. He was the first to discover sex linked genes and genetic assortment, segregation, and recombination, which put the fly as a model of genetic research. And cau se of its smallish size, ease of culture and short generation prison term, geneticists have been usingthe fly ever since. Drosophila sp. is cardinal of the few organisms whose entire genome is known and many of its genes have been identified and used in many other scientific researches. The very fast development enables this organism to develop from eggs to adult stage during 9-12 days in 25C. Usually the fly spends five days in the eggandlarval stages and four days in the immaturestage. The adult may live for several weeks.Drosophila sp. should not be reared in high temperatures (e.g. above 30C) that will result in sterilization or death of the flies or to low temperatures (e.g. below 10C) that also will result in a prolonged life cycle, maybe 57 days, and eventually reduced viability. Their body is commonly pale yellow to reddish brown to black in color, with large, red eyes and oval- mannequind wings, maybe sometimes it has some distinct black patterns. Also their wing venati on is peculiar to the entire family. The body form could be mutated due to culturing conditions, which produces offspring with body characters quietly different from parents.For instance, higher temperatures might alter the phenotype of the eye and body color, or may change the wing shape and size.The entire genus of Drosophila sp. contains to a greater extent than 15000 species and is very diverse in appearance, behavior, and breeding habitat (Gerhard Bchli, 1999-2006). Drosophilasp. found all over the world, but most(prenominal) of their species are predominant in the tropical regions. They are multivoltine species, and the northern species can hibernate. They breed in various kinds of decaying plants andfungalmaterials. The larvae of some species can also extend on fresh fruit and can sometimes be a pest (Mark Hoddle).Some other few species maybe switched in rules of order to bepara localises orpredators. Most of their species are attracted to bait of fermentedfruits or any ot her fermented odor, but little of them are not attracted to any kind of baits. Males usually congregate at patches of suitable breeding habitats to compete for females. SeveralDrosophilaspecies, such asD. melanogaster, are closely associated with humans thereby they are called asdomesticspecies. But most of Drosophila sp. have been accidentally to new areas due to anthropogenic activities and fruit transportation (Vilela, 1999 Van der Linde et al., 2006 Castrezana, 2007).The fruit fly varies in their reproductive capacity. D. melanogaster, breeds in rare, limited resources, haveovariesthat mature 10-20 eggs at a time, so that they can be laid together on one site. Others, those breed in more-abundant but less nutritious substrates, may only lay one egg per day. Only the adult stage feeds on veg matters, whereas larvae, the feeding immature stage, feed on yeast and microorganisms present on decaying breeding substrate. Their developmental time vary according to species. It is varied from 7 more than 60 days. Also, it may vary within the same species depending on the environmental factors such as temperature, breeding substrate, and crowding.In this study, D. melanogaster collected and cultured under laboratory conditions, using artificial substrates to investigate different immature stages and the mean developmental time for each stage.Materials and Methods1. Collecting and Culturing MediaDiet mixture of yeast, milk and cellulose was put in plastic bottle. The bottle was cut into two halves, the nick top half, which put inverted on the bottom half. The media recipe was devised as belowYeast 13gm take out 250gmCellulose tissue 20gmH2O 1LThis media is blended and placed in plastic collecting bottles containing crumpled paper toweling to prevent flies drowning. The media was stored at 30o for 2-3 days until fermented (Krivshenko 1963), so put outdoor to collect adult. The collecting bottle was checked twice daily (day and night). The collecting bottle left for three days to collect as much as possible of D. melanogaster flies. The collected individuals transferred to culturing bottle under the laboratory conditions (255C) at plant protection department, Food and Agriculture Sciences College, King Saud University, for conducting the experiment.fly oviposited in the diet. After 24 hrs, adult flies were removed from the bottles using their positive phototactic response and maintained in 20x20cm cage fitted with a sleeve and ply with 2.5 % sugar solution through cotton wicks. Small 50ml vials with culturing media were used for maintaining small larvae individually and avoid crowding. Number of larval developmental stages and time taken until pupal stage were recorded.Study area and periodThe study was conducted for 30 days (December, 2010) starting culturing step. Three collecting bottles were used in three selected sites for adult D. melanogaster battle array the educational farm of Food and Agriculture Sciences College, referred as site A , the main building of the College, referred as site B, and the students housing at King Saud University, referred as site C.Results and DiscussionTotal of 23 adults were collected in the three collecting bottles. Both Sites A and C were negative for adult fly. Eggs laid couldnt be observed since adult females put them in tiny cracks of the culturing media. 301 larvae have been recorded within 24hrs. The mean developmental time for larvae was 7 days to pupation. By the ordinal day, all larvae pupate (Fig. 1).Only single adult failed to emerge by the eleventh day. No adult were emerged until the end of month, which means that successful adult outgrowth took almost 22 days.The rapid development of early immature stages proved favorable conditions for larval development that was not quietly enough for the pupal stage development into adult emergence.The developmental period forfruit fly varies mainly with temperature, as with manyectothermic species. The shortest recorded development time (egg to adult), 7 days, is achieved at 28C (Ashburner and Thompson 1978, Ashburner et al., 2005). Development time increases at higher temperatures (11 days at 30C) cause of heat stress. The ideal development time at 25C is supposed to be 8.5 days as Ashburner and Thompson (1978), Ashburner et al., (2005), and Chiang and Hodson (1950) reported in previous investigations. Nevertheless, the findings of the current study showed longer development time peculiarly for late immature stage (pupa). This might be explained, as the temperature of the laboratory was not optimum (Crowding has no effect on development time since larvae were separated individually in culturing media. More over, under crowding increases the development time (Chiang and Hodson 1950), while the emerging flies are smaller (Chiang and Hodson 1950, Bakker 1961).