Cvetković et al 2020, Biologica Nyssana 11(2) 11 (2) December 2020: 129-138 DOI: 10.5281/zenodo.4393969 Effects of different sucrose concentrations on some parameters of the life cycle in two wild Drosophila species Original Article Vladimir J. Cvetković University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia biovlada@yahoo.com (corresponding autor) Saša S. Stanković University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia sasasta@gmail.com Vladimir Žikić University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia zikicvladimir@gmail.com Nikola Jovanović University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia nikolajov90@gmail.com Jovana Dimitrijević University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia jovana.dimitrijevic1@pmf.edu.rs Aleksandra Cvetanović University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia aleksandra.cvetanovic1@pmf.edu.rs Tatjana Mitrović University of Niš, Faculty of Sciences and Mathemat- ics, Department of Biology and Ecology, Višegradska 33, 18000 Niš, Serbia tatjanamitrovic3@gmail.com Received: May 06, 2020 Revised: November 19, 2020 Accepted: November 30, 2020 Abstract: The fruit flies collected from the wild can be easily cultured in laboratory for research purposes. On that occasion many similar recipes for cornmeal- based feeding media can be used for Drosophila cultivation. However, in these recipes concentrations of ingredients may differ what might imply a need to choose the recipe which is the most appropriate for culturing of wild Drosophila species. The aim of this study was to check how two wild species, Drosophila melanogaster and Drosophila suzukii respond to different sucrose concentration in feeding media by monitoring of life cycle key parameters. The total number of oviposited eggs, formed pupae and eclosed adults as well as dynamics of pupae formation and adult eclosion were recorded. The results showed that the sucrose concentrations of 160 gL-1 caused significantly lower number of formed pupae and eclosed adults in D. suzukii than at concentrations of 40 gL-1 and 80 gL-1. Prolonged and stretched dynamics of pupation and eclosion were recorded in D. melanogaster only at concentration of 160 gL-1. All tested Drosophila showed no differences in life cycle parameters between sucrose concentration of 40 gL-1 and 80 gL-1. Presented results can be helpful in deciding which cornmeal-based feeding media recipe to choose for cultivation of mentioned wild Drosophila species. Key words: Fruit fly, Drosophila melanogaster, Drosophila suzukii, feeding media, life cycle, sucrose concentration Apstract: Efekat različitih koncentracija šećera na neke parametre životnog ciklusa kod dve divlje vrste Drosophila Voćne mušice, prikupljene u prirodi, mogu se jednostavno gajiti u laboratoriji za potrebe različitih istraživanja. Za tu svrhu se može upotrebiti jedan od mnogih recepata sličnih sastojaka za pravljenje hranljive podloge, bazirane na kukuruznom grizu za gajenje drozofila. Međutim, u tim receptima koncentracije sastojaka mogu da variraju što može da podrazumeva potrebu da se odabere recept koji najviše odgovara za gajenje divljih vrsta drozofila. Cilj ovog istraživanja je da se praćenjem ključnih parametara životnog ciklusa proveri kako dve divlje vrste Drosophila melanogaster i D. suzukii reaguju na različite koncentracije šećera u hranljivoj podlozi. Praćeni su ukupan broj položenih jaja, ulutkanih i eklodiranih imaga kao i dinamike ulutkavanja i eklodiranja. Rezultati su pokazali da koncentracija šećera od 160 gL-1 izaziva značajno manje ulutkavanja i eklodiranja kod D. suzukii nego što je to pri koncentracijama od 40 gL-1 i 80 gL-1. Produžena i rastegnuta dinamika ulutkavanja i izleganja su zabeležene kod D. melanogaster samo pri koncentraciji od 160 gL-1. Kod svih testiranih drozofila nisu detektovane značajne razlike u praćenim parametrima životnog ciklusa između tretmana sa koncentracijama šećera od 40 gL-1 i 80 gL-1. Prikazani rezultati mogu biti od koristi prilikom odabira hranljivog medijuma baziranog na kukuruznom grizu za gajenje pomenutih divljih vrsta drozofila. Ključne reči: Voćna mušica, Drosophila melanogaster, Drosophila suzukii, hranljiva pod- loga, životni ciklus, koncentracija šećera © 2020 Cvetković et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially under the same license as the original. 129 Introduction The common fruit fly, Drosophila melanogaster Meigen is a famous model organism that has very wide implementation in biological sciences, primarily in genetic researches. There are many stock centers in the world that provide an array of different Drosophila stocks intended for experimental purposes. Nevertheless, for some research purposes, there is a need for Drosophila species that are obtained from the wild. On that occasion, the flies are caught and transferred into a laboratory ambient for further experiments. For instance, species from the genus Drosophila caught in the wild are very often processed in this way, for example D. melanogaster (Anagnostou et al., 2010; Lin et al., 2014; Gao et al., 2018). Spotted wing drosophila, Drosophila suzukii (Matsumura) is a very serious pest that has been extensively explored in laboratory conditions (Lin et al., 2014; Tochen et al., 2014; Silva-Soares et al., 2017; Fellous & Xuéreb, 2017; Schlesener et al., 2017). Since this species is introduced worldwide, it has been already recognized as a real threat on production of certain soft fruits that are of economic importance (De Ros et al., 2013; Benito et al., 2016; Mazzi et al., 2017). Also, the presence of this fruit pest fly is confirmed for the first time in Serbia in 2014 by Toševski et al. (2014). Thus, good laboratory practice is to provide optimal conditions including appropriate feeding media for such species to be transferred from the wild to a laboratory to obtain correct results from conducted experiments. Apart from laboratory Drosophila stocks, it is well-known that wild Drosophila species can be successfully cultured on cornmeal-based feeding media, even D. suzukii (Schlesener et al. 2017). There are many available recipes that are relevant for Drosophila culturing, for example at the site of Bloomington Drosophila Stock Center (https://bdsc. indiana.edu) or in papers (Lewis, 1960; Schlesener et al. 2017; Jovanović et al., 2018; Cvetković et al., 2020). However, different recipes for cornmeal- based feeding media imply different amounts of some ingredients such as carbohydrates and yeast. In addition, numerous articles are dealing with the influence of dietary yeast on D. melanogaster (Anagnostou et al., 2010) and in D. suzukii on life-history traits (Bellutti et al., 2018) or protein and carbohydrate ratio on larvae in D. suzukii (Silva-Soares et al., 2017) and dietary protein and carbohydrates balance in D. melanogaster (Lee, 2015). These studies suggested that carbohydrates and proteins play very important role in Drosophila lifespan so the special attention should be paid on the concentration of these two ingredients in the feeding media. According to Lushchak et al., (2014) the influence of dietary carbohydrate type and dosage is still poorly understood. In addition, we believe that among different recipes, the most appropriate recipe should be selected for wild Drosophila species that are transferred from natural to laboratory conditions because they cannot be adapted to artificial feeding media to the same extent as Drosophila laboratory stocks. Here, we ran a study to rapidly screen the degree of tolerance of the two wild species on three different sucrose concentrations in cornmeal-based feeding media at standard laboratory conditions by monitoring of the life cycle parameters. We believe that this will help to depict which cornmeal-based feeding media, in relation to sucrose concentration, is the most suitable for laboratory cultivation of wild D. melanogaster and D. suzukii collected in Southeastern Serbia. Also, the study should contribute to overall knowledge about influence of dietary sucrose on the life cycle of two Drosophila species. Material and methods Culturing conditions and types of feeding media The fruit flies were cultured at standard laboratory conditions which implies 60% of relative humidity, 12h/12h of the day/night light regime and constant ambient temperature at about 25±1 °C. Standard feeding media based on cornmeal was used for culturing of all flies from this experiment. Particularly, agar (6 gL-1), cornmeal (96 gL-1), sucrose (80 gL-1) and yeast (20 gL-1) prepared by cooking in dH2O with subsequent addition of fungicide as explained in our previous studies (Cvetković et al., 2015; Jovanović et al., 2016). For purposes of the experiment three different feeding media were prepared: All previously mentioned components were used in the same concentrations, except for the sucrose concentration that varied. Medium with sucrose concentration of 40 gL-1 – labeled as half, medium with sucrose concentration of 80 gL-1 – labeled as normal and medium with sucrose concentration of 160 gL-1 – labeled as double, were used. Fruit flies The wild D. melanogaster specimens were caught in the City of Niš, near the Faculty of Sciences and Mathematics (43°18’32.5”N; 21°55’22.9”E) in traps using grape as bait, during the September of 2018., leg. V. J. Cvetković. The adult flies were immediately transferred on the standard feeding media for culturing. For the starter generation, D. suzukii adults were incubated from larvae from the infested raspberries collected in private raspberry orchard near Lebane town (Southeastern Serbia), 130 BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species 131 42°55’56.1”N; 21°45’21.6”E, during the August of 2018., leg. S. S. Stanković. Immediately after eclosion they were transferred onto fresh standard media for culturing (Fig. 1). Captured fruit fly species were determined by V. Žikić and S. S. Stanković. In order to establish stock, the fruit flies from the wild were cultured on standard (normal) feeding media (see Culturing conditions and types of feeding media) for a dozen generations during 4 months. The referent laboratory strain of wild-type D. melanogaster Oregon-R-C strain (Bloomington Drosophila Stock center at Indiana University, USA), was used in this study as referent line because this strain is adapted on artificial cornmeal-based feeding media that was used in this experiment. Experimental protocol The whole experiment was performed at standard laboratory conditions (as explained in Culturing conditions and types of feeding media). For the D. melanogaster – referent line and two wild species flies, three different types of vials were prepared, ten of each, that contained half, normal and double concentration of sucrose in experimental feeding media. From referent laboratory stock culture (D. melanogaster) and wild flies established stocks (D. melanogaster and D. suzukii), pairs of young flies at the same age (5-7 days old) were chosen for further analyses, similarly as it was done in our previous research (Jovanović et al., 2018). In total, ten pairs were transferred into ten vials in each type of experimental feeding media to mate and lay eggs for two days. Afterwards, the adult flies were discarded and the oviposited eggs were counted immediately. Each day, number of formed pupae and subsequently eclosed adults was recorded. Statistical analysis The statistical analysis was performed within each of the three Drosophila group. The comparisons were performed by the following parameters: 1) the total numbers of oviposited eggs, 2) the total numbers of formed pupae and 3) the total numbers of eclosed adults, for each of the three sucrose concentrations. The percentage of pupation (percentage of formed pupae from hatched and survived larvae) and eclosion (percentage of eclosed adults from formed pupae) were calculated as it was described by Kinjo et al. (2014). The obtained values for the same parameter (percentage of pupation or eclosion) in feeding media with different sucrose concentration were compared within each of the Drosophila group. Statistically significant differences were determined with the Kruskall-Wallis ANOVA test for p<0.05. Further, post hoc Mann-Whitney test was used to determine significant differences between any of two compared values. Statistical analysis was conducted by using software package SPSS (SPSS Inc., Chicago, IL, USA). Results Statistical analysis of the life cycle parameters i.e. the total number of oviposited eggs, formed pupae and eclosed adults are presented in Tab. 1. The presented mean values and standard deviations were obtained based on 10 replicates for each strain, D. Fig. 1. Drosophila suzukii - the starter generation. A – larvae (showed with blue arrow) from infested raspberry. B – eclosed adults, incubated from infested raspberries, transferred on standard fresh feeding media for culturing. C – pupae (showed with yellow arrows) within the feeding media, the first laboratory generation of captured D. suzukii. Photos by V. J. Cvetković BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species 132 melanogaster-referent line, wild D. melanogaster and D. suzukii. All calculations were done for each of three feeding media types. The only significant difference in percentage of pupation between normal and double concentration were recorded in D. suzukii (Fig. 2). The only significant differences in percentage of eclosion were observed between normal and double group within wild D. melanogaster and normal compared to half and double within D. melanogaster – referent line (Fig. 3). In D. melanogaster – referent line, the peak of larval pupation was recorded on the fourth day, fifth and the seventh day in half, normal and double sucrose concentration, respectively (Fig. 4). The peak of adult eclosion was recorded at the fifth day in half and normal and at the eighth day in double sucrose concentration (Fig. 4). In addition, the peaks were higher and the pupation, as well as eclosion, lasted shorter in groups with half and normal sucrose concentration than in the group with double of the sucrose concentration. In the wild D. melanogaster, the peak of larval pupation was recorded on the fourth day in normal and double and the eighth day in half concentration of sucrose (Fig. 5). The peak of adult eclosion was recorded also on the fourth day in half and normal and on the eighth day in a double concentration of sucrose (Fig. 5). In addition, the peaks were higher and the pupation, as well as eclosion, Species Sucrose concentration Oviposited eggs Formed pupae Eclosed adults D . m el an og as te r half 57.63 30.13 29.63 ±19.04 ±11.42 ±11.61 normal 71.5 41.1 40.7 ±21.19 ±14.49 ±14.24 double 65.87 37.88 36.38 ±29.43 ±11.51 ±11.36 D . m el an og as te r re fe re nt li ne half 71.22 62.22 59.11 ±24.54 ±20.28 ±17.88 normal 75.38 * 70.38 * 69.63 * ±20.70 ±16.49 ±16.55 double 55.4* 50.1 * 48.00 * ±19.98 ±18.54 ±17.51 D . s uz uk ii half 11.5 8.6† 8.1† ±8.22 ±5.68 ±5.5 normal 12.2 8.8‡ 8.5‡ ±6.05 ±2.3 ±3.2 double 7.1 2.9 †‡ 2.7 †‡ ±5.09 ±3.6 ±3.3 Table 1. Life cycle parameters in D. melanogaster-referent line, wild D. melanogaster and D. suzukii cultured on feeding media with different sucrose concentrations. Mean values are presented with ± standard deviation. Fig. 2. Percentage of pupation in D. melanogaster, D. melanogaster-referent line and D. suzukii cultured on feeding media with half, normal and double concentration of sucrose. The lower case letter “a” marked the two values that are significantly different. Differences were determined using Kruskall-Wallis ANOVA and post hoc Mann-Whitney test. Statistical significance was considered for p<0.05 -Values marked with the same symbol * are significantly different within D. melanogaster – referent line -Values marked with the same symbol † and/or ‡ are significantly different within D. suzukii group. -Significant differences were considered for p<0.05 BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species lasted shorter in groups with half and normal sucrose concentration than in double of the sucrose concentration. In D. suzukii line, the peak of larval pupation was recorded on the third, fourth and the seventh day in half, normal and double sucrose concentration, respectively (Fig. 6). The peak of adult eclosion was recorded on the fourth, fifth and the eighth day in half, normal and double concentration of sucrose, respectively (Fig. 6). Additionaly, the peaks were higher in groups with half and normal sucrose concentration than in double of the sucrose concentration but the duration of the pupation and eclosion was mostly the same in all three groups. Discussion All three parameters of the life cycle – the total number of oviposited eggs, formed pupae and 133 Fig. 3. Percentage of eclosion in D. melanogaster, D. melanogaster-referent line and D. suzukii cultured on medium with half, normal and double concentration of sucrose. The same lower cases letter (a, b or c) marked the two values that are significantly different. Differences were determined using Kruskall-Wallis ANOVA and post hoc Mann-Whitney test. Statistical significance was considered for p<0.05. Fig. 4. Dynamics of pupation and eclosion in D. melanogaster – referent line. A – Dynamics of larval pupation and B – Dynamics of adult eclosion. Half, normal and double refers to sucrose concentration in feeding media. BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species 134 eclosed adults were not significantly different in the wild D. melanogaster cultivated on feeding media with different sucrose concentrations. According to these results, the wild D. melanogaster strain used in this experiment were tolerant to variation of sucrose concentration in feeding media at standard ambient conditions. In D. suzukii, at double sucrose concentration, the total number of formed pupae and eclosed adults were significantly lower (p<0.05) than in half and normal sucrose concentrations. However, the total number of oviposited eggs was not significantly different between groups with different sucrose concentrations. In some way, the higher sucrose concentrations disrupted incubation of the eggs and/or development of the hatched larvae until the pupation stage. Also, in the D. melanogaster-referent line significantly lower (p<0.05) numbers of oviposited eggs, formed pupae and eclosed adults were observed in double than in normal sucrose concentration. A possible explanation is that the higher sucrose concentration in feeding media probably stimulates the increase of the products of fermentation. The higher levels of the fermentation products (ethanol, carbon dioxide etc.) may have a negative impact on larval hatching, development as well as pupation. Also, it might have a negative effect on the number of oviposited eggs that was significantly lower in double concentration in D. melanogaster – referent line. This hypothesis is waiting to be confirmed or rejected in further experiments because this time we did not measure the levels of fermentation products in our experiment. A lower percentage of pupation were recorded in all three types of feeding media in the wild D. Fig. 5. Dynamics of pupation and eclosion in wild D. melanogaster. A – Dynamics of larval pupation and B – Dynamics of adult eclosion. Half, normal and double refers to sucrose concentration in feeding media. BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species 135 melanogaster while in the D. melanogaster – referent line was higher. This means that the laboratory Drosophila strain is well adapted on applied cornmeal feeding media, as it was expected. The percentage of pupation values in D. suzukii were about 90% in average. As we were not able to count the hatched larvae, the much lower percentage of pupation could mean that many of the eggs were not fertilized or/and that many larvae have died before pupation in wild D. melanogaster. Thus, these results indicate that standard laboratory conditions and applied feeding media (for medium details see section: Culturing conditions and types of feeding media) influenced pupation in wild D. melanogaster. Besides previous observations, in wild D. melanogaster percentage of pupations were not significantly different in all three sucrose concentrations, as in the D. melanogaster – referent line, while in D. suzukii percentage of pupation was significantly lower in double concentration compare to normal sucrose concentration. We propose one possible explanation for such a result. During pupation, larvae of D. melanogaster mostly went out of the feeding media and formed pupae on the walls of the vials where they were cultivated. In D. suzukii, pupae are formed mostly within the feeding media. Thus, the explained effects of high sucrose concentrations in feeding media and the consequent presence of higher levels of fermentation products like ethanol and carbon dioxide might affect the pupation process in this case by affecting the larvae hatching or/and eggs incubation or/and larvae survival. As we did not count the number of hatched larvae, so we cannot state at which state the detrimental effect occurred, Fig. 6. Dynamics of pupation and eclosion in wild D. suzukii. A – Dynamics of larval pupation and B – Dynamics of adult eclosion. Half, normal and double refers to sucrose concentration in feeding media. BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species this observation remains to be tested in forthcoming analysis. Gao et al. (2018) showed that both adults and larvae of D. melanogaster were more tolerant of environmental ethanol than D. suzukii (Gao et al., 2018). This is consistent with our observation about the influence of possible higher levels of ethanol in double sucrose concentrated media. In addition, it has long been known that D. melanogaster was more tolerant on alcohol compared to other Drosophila species (McKenzie & Parsons, 1972). On the other hand, a minor difference in the percentage of eclosion in both wild Drosophila species as in the D. melanogaster – referent line in any type of the tested feeding media. This could mean that the process of incubation from pupal to the adult stage was not affected in the same percentage as the pupation process by different sucrose concentrations in any experimental group since pupal mortality was very low in all Drosophila groups. Only significant differences showed that the percentage of eclosion was significantly affected by double sucrose concentration comparing with normal within the wild D. melanogaster group. Also, within D. melanogaster – referent line, in double and half concentration percentage of eclosion was significantly affected compared to normal concentration (the percentages of eclosion were above 95%). However, these differences were minimal in both D. melanogaster groups. Interestingly there were no significant differences between the percentage of eclosed flies in different feeding media within D. suzukii group, so the different sucrose concentrations did not affect D. suzukii at the pupal stage. It was already stated that in the wild D. melanogaster there were no significant differences for the total number of formed pupae and eclosed adults at different sucrose concentrations. But the differences were observed at dynamics of pupation and eclosion. The peaks for the dynamic of these parameters in half and standard concentration was on the fourth day while in double was about the eighth day. The pupation and eclosion were very prolonged and stretched at double concentration compared with the half and standard within the wild D. melanogaster. Analyzing these parameters in the D. melanogaster – referent line group and D. suzukii group, a similar pattern could be observed in the double sucrose concentration. Nevertheless, in D. suzukii the other two groups, half and normal, also express prolonged pupation and eclosion without pronounced peaks unlike both D. melanogaster groups. Thus, due to its detrimental effect in all groups the double sucrose concentration in feeding media caused prolonged and extended pupation and eclosion. The reason might be the same, explained in previous paragraph, the detrimental effect of the higher level of fermentation products. On the other hand, half concentration did not cause any visible effect on dynamics of pupation and eclosion in any Drosophila group. Overall, our findings is in accordance with the conclusion of Fellous & Xuéreb (2017) that high sugar concentrations are detrimental for development of the D. suzukii. Also, Lushchak et al., (2014) stated that sucrose, commonly used for Drosophila laboratory food, shorten lifespan and contribute to lower egg-laying capability in D. melanogaster. According to the results and previous observations, the detrimental effects, especially of the highest applied sucrose concentration are obvious in Drosophila. Even more, D. suzukii was more sensitive to higher sucrose concentration than D. melanogaster. There are many available cornmeal-based feeding media recipes that can be applied for laboratory culturing of Drosophila species, but the concentrations of ingredients may vary in different recipes. Despite differences in ingredients, many of them can be used for Drosophila culturing. For example, some fly food recipes are available at the site of Bloomington Drosophila Stock Center from Indiana University in USA (https://bdsc.indiana.edu). Schlesener et al. (2017) reported modified cornmeal- yeast-glucose-agar medium that are suitable for D. suzukii rearing. The composition of standard feeding media that we use in this experiment were not the same but it is quite similar as in Schlesener et al. (2017). We found that one of the differences between the feeding media that we used from the mentioned one is in yeast concentration. Particularly, we used almost twice smaller concentration of yeast, as a protein source, what in addition to the highest applied sucrose concentration also might influenced development of the D. suzukii in our experiment. However, we did not vary yeast concentration in this experiment because it was not the subject of this research and in all treatment media was added in same amount according to one of the recipe (see section: Culturing conditions and types of feeding media) that we use for laboratory Drosophila stocks culturing. Also, Fellous & Xuéreb (2017) reported that intermediate protein concentration is optimal for D. suzukii development. These observations indicate that protein concentration in feeding media should be taken into consideration when choosing appropriate feeding media for wild D. suzukii and we believe also for D. melanogaster because it is known that dietary balance of proteins and carbohydrates concentrations is important because its influence on Drosophila lifespan (Lushchak et al., 2014; Lee, 2015). 136 BIOLOGICA NYSSANA ● 11 (2) December 2020: 129-138 Cvetković et al. ● Effects of different sucrose concentrations on some pa- rameters of the life cycle in two wild Drosophila species Conclusion According to our findings the sucrose concentration of 160 gL-1 in the feeding media caused significantly lower number of formed puape and eclosed adults in D. suzukii than at concentrations of 40 gL-1 and 80 gL-1. In all tested Drosophila there were no significant differences in analyzed life cycle parameters between sucrose concentrations of 40 gL-1 and 80 gL-1. Moreover, there were no significant differences between any of three tested sucrose concentrations for numbers of laid eggs, pupation and eclosion in wild D. melanogaster. The dynamics of pupation and eclosion were prolonged and stretched in wild D. melanogaster at 160 gL-1 sucrose concentration while in D. suzukii was mostly the same as in 40 gL-1 and 80 gL-1. We believe that the presented results might be helpful in deciding which cornmeal-based feeding media, in relation to the sucrose concentration, should be selected for the cultivation of mentioned Drosophila species that originating from the wild. Also, the obtained results represent contribution to the overall knowledge of the influence of dietary sucrose on lifecycle of two Drosophila species. Acknowledgement. This study was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (contract number: 451-03-68/2020-14/200124). 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