Patent Application: US-1909708-A

Abstract:
this invention relates to a novel method of attracting and trapping drosophila species and a composition therefor . a method of attracting flies in the family drosophilidae which comprises preparing an attractant which is a combination of a moistening agent , yeast and dried and powdered vegetable matter host substrate , including banana , apple , pear , papaya , mango , orange , tomato , or vegetables , including potato and squash , and placing this attractive lure in a trap .

Description:
throughout the following description specific details are set forth in order to provide a more thorough understanding to persons skilled in the art . however , well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure . accordingly , the description and drawings are to be regarded in an illustrative , rather than a restrictive , sense . all trapping experiments that yielded quantitative data were set up as randomized complete blocks . because different numbers of fruit flies were tested in each replicate , the data for each replicate were converted to percentages of the total number of flies captured . if necessary , percentages were transformed by arc sin √ 0 . 01x to achieve normality , before being subjected to anova , and ( when there were more than two means ) the tukey - kramer hsd test . in all cases α = 0 . 05 . mixed sexed adult fruit flies , drosophila melanogaster , were obtained from a colony maintained at the department of biological sciences , simon fraser university , burnaby , b . c . fruit flies were reared on decaying overripe bananas in screened cages at a constant 24 ° c . and a photoperiod of 12 : 12 ( l : d ). adults of both sexes were used in all experiments . experiment 1 compared two types of traps . the first was the commercially available 225 ml springstar spice - jar trap , with a flip - top lid that exposed three 5 mm diameter holes as entry ports , water with a dash of detergent in the bottom of the trap to capture flies that entered through the lid , and a polyethylene lure vessel that floated in the water . the second was a miniaturized peters trap consisting of the same spice jar , with the lid closed , a 5 mm diameter drinking straw cross bridge ( with a 5 mm wide cut - out at mid point that allowed flies to enter the interior of the trap ) spanning the 5 . 5 cm diameter of the jar , a slice of orange in the bottom as a lure , and a 4 . 5 × 8 cm sticky card ( both sides ) placed upright in the jar to capture flies that entered the trap . the two types of trap were tested in three groups of four pairs ( 12 replicates ) randomly placed side by side for one hour in each of four corners of a large screened cage containing hundreds of fruit flies . observations during the one - hour trapping periods indicated that fruit flies could enter and leave the springstar trap , but that no flies left the peters trap once they entered . surprisingly , a total of 1 , 209 fruit flies were captured in the 12 peters traps in experiment 1 , almost three times the number captured in the springstar traps ( table 1 ). the results do not reveal whether the superiority of the peters trap resides in the natural fruit lure , the method of entry into the trap , the sticky card capture device , or some combination of factors . nonetheless , the results do show that the peters trap design concept can be miniaturized for catching very small insects like fruit flies , and that a sticky card to trap flies that enter an peters trap can be used to replace the water trapping medium . experiment 2 compared the miniaturized peters trap fitted with an 8 mm diameter drinking straw entry gate against the springstar spice - jar trap . both traps had a banana slice lure and identical 4 . 5 × 8 cm sticky card capture devices , so that the only difference between traps was the method of entry . four pairs of traps ( replicates ) were tested for one hour on each of two days for a total of eight replicates . the traps in each pair were randomly positioned side by side at the front or rear of a large screened cage as above . traps of the peters design captured 108 fruit flies in total , slightly ( but not significantly ) more than the 92 flies captured in springstar traps ( table 1 ). this result shows that entry of fruit flies into the peters trap is at least as good as for the springstar trap . the slight superiority of the peters trap may be because of the lack of escapes . table 1 . results of experiments 1 - 3 , showing that traps of the peters design , fitted with transverse entry tubes with a cut - away portion at mid - point that allows flies to gain entry into the interior of the trap , and also containing a sticky card capture device , compare very favourably with the commercial springstar trap , and also showing that increasing the size of the peters trap will increase the efficacy of the trap . experiment 3 compared the miniaturized peters trap with a larger 21 . 5 × 8 cm cylindrical 1 l commercial peters trap used for trapping other insects . both traps were baited with banana slice lures . the miniaturized trap had a 4 . 5 × 8 cm sticky card and an 8 cm diameter entry gate as in experiment 2 , while the larger trap had a 5 × 18 cm sticky card capture device . two replicates were run at different times in a residential apartment , with the traps in each pair randomly placed on a table . unexpectedly , the larger trap captured 2 . 4 times more fruit flies than the smaller version ( table 1 ). this result demonstrates that increasing the diameter of the entry gate , the volume of the interior chamber in the trap , or the size of the sticky card capture surface , or some combination of these factors , can greatly increase the numbers of fruit flies captured . drosophila melanogaster were reared in 175 ml plastic bottles containing 10 g of medium comprising : water , agar , cornmeal , bakers &# 39 ; yeast , molasses , 10 % p - hydroxy - benzoic acid and methyl 4 - hydroxybenzoate in 95 % ethanol . the bottles were kept at 29 ° c . and 60 % rh under a 16 : 8 h light : dark regime . only flies enclosing within the previous 24 h period were used in an experiment . two experiments were conducted , each with replicates of four treatments tested within separate 38 × 38 × 38 cm clear plastic cages . up to four replicates ( cages ) were completed per day . white cardboard was placed between cages to minimize any chemical or visual interference . treatments were offered in 40 ml polyethylene vials containing a 2 . 5 × 10 cm piece of waxed cardboard treated on one side with tanglefoot ® ( tanglefoot co ., grand rapids mich .) to capture responding insects . approximately 20 mixed sex adult d . melanogaster in a 9 . 5 cm diameter plastic petri dish were placed in the middle of the cage floor for 20 min , after which the lid was removed , allowing the flies to respond to the treatment vials for 24 h at 26 ° c . and a 16 : 8 l : d regime . banana chip powder treatments were prepared from aloha brand banana chips ( dole food co , inc ., honolulu , hi .) which contained deep fried banana slices , coconut oil , sucrose and / or honey . the chips were crushed into a fine powder , water was added ( 20 ml per 3 g of powder ) and the mixture was stirred into a paste . after 20 min , the paste was added in 8 . 5 g aliquots to the 40 ml test vials . banana chip powder with yeast and water was prepared in the same manner as the above treatment , except that 0 . 05 g of bakers &# 39 ; yeast ( canada safeway ltd , calgary , alberta ) was thoroughly mixed with the chip powder before the water was added . mashed banana was made up by mixing 10 ml of water with 5 g of crushed banana . the mashed banana plus yeast treatment was identical to the mashed banana treatment , except that 0 . 05 g of yeast was added to the 5 g of crushed banana before the water was added . both banana treatments were also tested as 5 g aliquots in the 40 ml test vials . treatments in experiment 4 ( n = 12 replicates ) included : 1 ) powdered banana chips plus yeast plus water , 2 ) mashed banana plus water , 3 ) mashed banana plus yeast plus water and 4 ) unbaited control . test vials were randomly placed in the four corners of each cage . four replicates were run per day for three days . treatments in experiment 5 ( n = 10 replicates ) were the same as in the experiment 4 , except that the unbaited control was replaced with banana chip powder plus water . test vials were grouped together in random placement in a 2 × 2 grid in one corner of each cage . after 24 h , the number of flies on each sticky card was counted . in experiment 4 , traps baited with banana chip powder plus yeast , mashed banana or mashed banana plus yeast all captured significantly more fruit flies than unbaited control traps , but there was no significant difference among the three treatments ( table 2 ). this experiment demonstrates that powdered banana chips can effectively replace banana as an attractive stimulus for fruit flies . when the four stimuli in experiment 5 were placed close together , traps baited with powdered banana chips plus yeast unexpectedly captured significantly more flies than traps baited with any of the other stimuli , over twice as many flies as mashed banana , and over three times as many flies as mashed banana plus yeast or powdered banana chips ( table 3 ). these results show that when the flies are challenged with a choice of traps at close range , they clearly prefer the yeast plus powdered banana plus water lure over traps baited with a natural fruit lure comprised of mashed banana . in spite of the efficacy of the powdered banana chips plus yeast lure in experiment 5 , it would not be practical to require that users mix up a paste to bait a trap for operational or commercial purposes . moreover , any water - based paste exposed to the air would be expected to dry out within a day , effectively terminating any attraction . nonetheless , the results show promise for a powdered banana plus yeast lure that could replace the fruit itself , without having to employ an expensive lure based on a blend of synthetic chemicals . to ensure the practicality of the lure used in the trap for operational and commercial purposes and to prevent extra work and mess when mixing a paste to bait a trap , teabags were proposed as a receptacle to keep the bait contents together and wet . however , when teabags are exposed to the air they quickly dry out . furthermore , because the most efficient trap would contain a sticky card to prevent escape , the teabag needed to stay wet yet not affect the adhesive on the sticky card . to avoid drying out the bait and reducing its effectiveness , we decided to add a humectant that could retain water yet not alter the effectiveness of the bait . the inventors &# 39 ; objective was to construct a moist teabag without water leakage . polyacrylamide gel powder was proposed and in experiment 6 a series of teabags were constructed containing powdered banana chips , yeast and different weights of the gel powder . treatment contents were placed in 3 . 8 × 6 . 3 cm teabags ( t - sac brand gmbh , hannover , germany ). each teabag contained 1 . 0 , 0 . 5 , 0 . 1 or 0 . 05 g polyacrylamide gel powder ( integra tech associates , overland park , kans . ), added to 0 . 1 g fleischmann &# 39 ; s traditional active dry yeast ( ach food companies inc ., memphis , tenn . ), and 1 . 0 g banana chip powder . banana chip powder treatments were prepared from crushed banana chips ( bulk food , canada safeway ltd , calgary , alberta ) which contained deep fried banana slices , coconut and / or palm oil , sucrose and / or honey . teabags were dipped in water for 10 sec , the excess water was allowed to drip off , and the bags were left in the miniaturized peters traps described in example 1 , experiment 2 , except that the 8 mm diameter drinking straw was replaced by a hard acrylic plastic entry tube ( 6 mm inside diameter , 9 mm outside diameter ), without sticky cards . they were observed daily for four days , then daily for four days after a two day break . teabags containing 0 . 1 to 0 . 05 g polyacrylamide gel powder had four desirable characteristics . they did not burst after being dipped in water , they soaked up water faster than teabags with 1 . 0 or 0 . 5 g of polyacrylamide gel powder , they retained enough water to completely wet the rest of the teabag contents and they stayed wet to the touch longer than the other four weights of teabags . therefore , 0 . 05 g polyacrylamide gel powder was selected as the optimal amount . test of powdered dehydrated banana versus powdered banana chips as a host substrate experiment 7 was conducted to determine if fruit flies , drosophila melanogaster , reared as in example 1 , were more attracted to powdered dehydrated banana than powdered banana chips . four groups of four replicates each were run for 24 h in four different time periods , for a total of 16 replicates . each replicate had two treatments , so that for each time period , eight traps , consisting of four randomly - assigned treatments within each pair , were positioned equidistant around the periphery of the floor of a 133 × 66 × 47 cm clear plastic cage . treatments were offered in the miniaturized peters trap described in example 1 , experiment 2 , except that the 8 mm diameter drinking straw was replaced by the hard acrylic plastic entry tube described in example 3 , and the sticky cards ( better world manufacturing inc ., fresno , calif .) were 9 . 2 × 5 . 4 cm , and were sticky on one side only . treatment contents were placed in 3 . 8 × 6 . 3 cm teabags ( t - sac brand gmbh , hannover , germany ). each teabag contained 0 . 15 g fleischmann &# 39 ; s traditional active dry yeast ( ach food companies inc ., memphis , tenn . ), 0 . 05 g polyacrylamide gel powder ( integra tech associates , overland park , kans .) and 1 . 5 g of either banana chip powder ( treatment 1 ) or dehydrated banana powder ( treatment 2 ). banana chip powder treatments were prepared as in example 3 , experiment 6 . dehydrated banana powder treatments were prepared from freeze dried banana powder ( nature &# 39 ; s flavors , orange , calif .) which contained only bananas . teabags were dipped in tepid tap water for 10 sec , excess water was allowed to drip off , and the teabag was dropped into a trap . the sticky card was bent in the middle lengthwise , the backing removed and the card was inserted upright into the trap . a number of mixed sex drosophila melanogaster in a 16 cm diameter covered plastic dish were placed in the middle of the cage floor for 5 min , after which the lid was removed and the flies allowed to respond to the treatment teabags for 24 h at 22 ° c . the number of fruit flies on each sticky card was then counted . traps with teabags containing the dehydrated banana powder teabags caught significantly more fruit flies than traps with teabags containing pulverized banana chips ( table 4 ). the superiority of the teabags containing banana powder was consistent for each group of four replicates . this experiment demonstrates that dehydrated banana powder is an effective replacement for crushed banana chips when used as a lure for fruit flies . because the polyacrylamide gel powder eventually breaks down into its carcinogenic monomer constituents , we decided to determine whether it could be replaced by an alternative humectant . four food - grade humectants were tested in experiment 8 : agar , carrageenan gum , guar gum and xanthan gum . teabags were constructed as in example 4 , using only the dehydrated banana powder and 0 . 2 g of agar powder ( westpoint distributors ltd ., vancouver , b . c . ), carrageenan gum powder ( genugel ® carrageenan type ci - 102 , cp kelco u . s . inc ., chicago , ill . ), guar gum powder ( bulk food , famous foods , vancouver , b . c .) or xanthan gum powder ( kelzan ® s , cp kelco u . s . inc ., chicago , ill .). these teabags were dipped in water for 10 sec , the excess water was allowed to drip off , and the bags were left in open air . they were observed daily for three days , and after five days . teabags containing carrageenan gum gel powder had three desirable characteristics . they had no residual odour , they did not swell up after being dipped in water , and they stayed wet to the touch longer than the other three types of teabags . therefore , carrageenan gum gel was selected as an alternative to polyacrylamide gel powder , and was used in all subsequent experiments . experiment 9 was conducted to determine if fruit flies , drosophila melanogaster , reared as in example 1 , were more attracted to powdered dehydrated banana than a slice of banana . four groups of four replicates each were run in the miniaturized peters trap as described in example 4 . for the first treatment , teabags contents included 2 . 0 g of freeze dried banana powder ( nature &# 39 ; s flavors , orange , calif . ), 0 . 2 g of fleischmann &# 39 ; s traditional active dry yeast ( ach food companies inc ., memphis , tenn .) and 0 . 2 g of carrageenan gum powder ( genugel ® carrageenan type ci - 102 , cp kelco u . s . inc ., chicago , ill .). for the second treatment , banana slices were cut from bananas obtained at the local grocery and cut into 2 . 0 g pieces . for each replicate , teabags were dipped in tepid tap water for 10 sec , excess water was allowed to drip off , and the teabag was dropped into a trap . cut slices of banana were dropped into the other trap . the sticky card for each trap was bent in the middle lengthwise , the backing removed and the card was inserted upright into the trap . a number of mixed sex drosophila melanogaster in a 16 cm diameter covered plastic dish were placed in the middle of the cage floor for 5 min , after which the lid was removed and the flies allowed to respond to the baited traps for 24 h at 22 ° c . the number of fruit flies on each sticky card was then counted . unexpectedly , traps with teabags containing the dehydrated banana powder caught 62 . 4 % of all flies captured , significantly more than traps baited with a slice of banana ( table 5 ). this experiment demonstrates that dehydrated banana powder is a superior replacement for a slice of banana when used as a lure for fruit flies . four replicates were run in miniaturized peters traps as described in example 4 . teabags were prepared as described in example 6 . treatments included teabags that were either wet 48 h previously , wet 48 h previously and then re - wet immediately before the experiment , and freshly wet teabags . all teabags were prepared by dipping in tepid tap water for 10 sec , allowing excess water to drip off , and dropping the teabag into a trap . sticky cards were bent in the middle lengthwise , the backing removed and the cards inserted upright into the traps . a number of mixed sex drosophila melanogaster in a 16 cm diameter covered plastic dish were placed in the middle of the cage floor for 5 min , after which the lid was removed and the flies allowed to respond to the baited traps for 24 h at 22 ° c . the number of fruit flies on each sticky card was then counted . unpredictably , regardless of re - wetting , teabags that had been wet 48 h previously caught more than double the number of fruit flies than freshly wetted teabags . this experiment demonstrates that banana powder teabags with carrageenan gel powder as a humectant increase in potency over the first 48 h after wetting , and continue to attract and capture fruit flies for at least three days . the results also demonstrate that at least for three days duration , re - wetting is not necessary . emission of co 2 from teabags with and without cheese whey when all components of the teabag are considered , the limiting factor for longevity of attractiveness may be the rapidity with which the yeast uses up the available substrate , resulting in a decrease in co 2 production . the co 2 generated from yeast is a fruit fly attractant and adding a source of galactose to increase the longevity of co 2 production by the yeast may prolong the attractiveness of a teabag lure . experiment 11 was conducted to determine how long gas , assumed to be co 2 , was generated from dehydrated banana powder teabags , with and without cheese whey as a source of galactose . an apparatus to observe the generation of co 2 was constructed . paired cylindrical 225 ml plastic jars were each closed with an airtight rubber stopper , through which a plastic tube was inserted . the plastic tube was attached to a glass pipette with the thin end of the pipette submerged in water in a glass test tube . the water was dyed green to aid in observation . this set up allowed for observation of gas escaping from the trap and bubbling into the green water . teabags were constructed as described in example 4 . teabags with cheese whey were loaded as above , with the addition of 0 . 5 g powdered cheese whey ( bulk food product , famous foods , vancouver , b . c .). teabags were dipped in tepid tap water for 10 sec , excess water was allowed to drip off , and each teabag was dropped separately into one of the plastic jars . rates of escaping gas were determined by counting bubbles released through the dyed water for 10 min observation periods as indicated in table 7 . unexpectedly , experiment 11 demonstrated that addition of cheese whey to the teabag more than doubled the duration that the yeast produced a gas presumed to be co 2 ( table 7 ). twelve replicates were run comparing the number of fruit flies caught in miniaturized peters traps as described in example 4 , versus three commercially - available traps : the deadeasy fruit fly trap ( dead easy pest control , victoria , b . c ), the 960 vector fruit fly trap ( whitmire micro - gen research laboratories , inc ., st . louis , mo . ), and , natural catch fruit fly trap ( bio - logic , inc ., milwaukee , oreg .). teabags were prepared as described in example 6 . each treatment included one trap of each type set up according to the instructions on the label . teabag lures were prepared as in example 6 . they were dipped in tepid tap water for 10 sec , excess water was allowed to drip off , and they were dropped into a miniaturized trap . sticky cards were bent in the middle lengthwise , the backing removed and the cards inserted upright into the traps . a 16 cm diameter covered plastic dish containing mixed sex drosophila melanogaster was placed in the middle of the bioassay cage floor for 5 min , after which the lid was removed and the flies were allowed to respond to the baited traps for 24 h at 22 ° c . the number of fruit flies on each sticky card ( miniaturized peters traps ) or in the liquid trapping medium ( commercially - available traps ) was then counted . surprisingly , the miniaturized peters traps baited with teabag lures containing freeze dried banana powder , bakers &# 39 ; yeast and a humectant caught significantly more fruit flies than any other trap tested ( table 9 ). this result demonstrates clearly that the miniaturized peters trap with the new teabag lure is more effective at catching fruit flies , drosophila melanogaster , than three widely - available commercial traps . while a number of exemplary aspects and embodiments have been discussed above , those of skill in the art will recognize certain modifications , permutations , additions and sub - combinations thereof . it is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications , permutations , additions and sub - combinations as are within their true spirit and scope . baker , t . c ., j . zhu and k .- c . chung . 2003 . fruit fly attractant compositions . u . s . pat . no . 6 , 543 , 181 . muramatsu , s . 1996 . insect trap with liquid attractant . u . s . pat . no . 5 , 490 , 349 . rojas , g . m ., j . a . morales - 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