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Öğe Advances in theory, data analysis, and application of the age-stage, two-sex life table for demographic research, biological control, and pest management(E Schweizerbartsche Verlagsbuchhandlung, 2023) Chi, Hsin; Kavousi, Aurang; Gharekhani, Gholamhossein; Atlihan, Remzi; Ozgokce, Mehmet Salih; Guncan, Ali; Gokce, AyhanThis paper reviews and introduces innovative research pertaining to the age-stage, two-sex life table. The main topics discussed are: (1) Analysis of data involving group-reared life table studies. We address the rationale behind the data analysis used when constructing a group-reared life table. Proper analysis of grouped-reared life table data enables the collection of realistic and applicable data for ecological studies, devising efficient mass-rearing programs and formulating pest management routines using time-and labor-saving group-rearing methods. (2) The bootstrap-match technique. This novel technique is applicable to those instances when constructing a complete life table involves collecting the immature independently from the adult data. (3) Application of the set theory in life table research. This procedure enables a mathematical description of the population structure and bootstrap samples. (4) Application of the multinomial theorem. Using the multinomial theorem enables calculation of the exact probability of bootstrap samples. (5) Inclusion of infertile bootstrap samples. Because it is impossible to calculate the intrinsic rates of increase for infertile samples, they are normally omitted in life table analysis. Inclusion of these infertile bootstrap samples produces an unbiased life table analysis. (6) The Cartesian product. The Cartesian product of two sets produces the complete coverage of all possible differences. We compared the paired bootstrap test, the Cartesian paired test based on bootstrap results, and the Cartesian paired test based on the multinomial theorem. (7) Integration of life table data with predation data. This procedure, which is especially relevant to biological control programs, enables a comprehensive study of the predator-prey relationship. (8) Computer simulation based on life tables. Population projection based on the age-stage, two-sex life table not only provides the means to predict the dynamics of stage structures of a given pest population, but also provides an insight into the dynamics of predation capacity of the predator population. (9) Problems in life table research. Each of the subjects discussed is crucial for the theoretical advancement and practical applications of scientific demographic research.Öğe Antifeedant activity and growth inhibition effects of some plant extracts against larvae of Colorado potato beetle [Leptinotarsa decemlineata Say (Col: Chyrsomelidae)] under laboratory conditions(ENTOMOLOGICAL SOC TURKEY, EGE UNIV, 2015) Alkan, Mustafa; Gokce, Ayhan; Kara, KenanAntifeedant activity and growth inhibition effects of Achillea millefolium L. (Asteraceae), Heracleum platytaenium Boiss (Apiaceae), and Humulus lupulus L. (Cannabaceae) extracts were tested on the third instar larvae of Colorado potato beetle (Leptinotarsa decemlineata Say, Col: Chyrsomelidae) under laboratory conditions. Plant extracts were obtained treating "cones" of H. lupulus, leaves and stems of H. platytaenium and leaves, stems and flowers of A. millefolium with methanol using maceration technique. The plant extracts (50 g/L) were applied to potato leaflets and consumption area for individual insect was measure with a planimeter after 24, 48 and 72h. The single dose screening bioassay revealed that all tested plant extracts possessed antifeedant activity against the beetle larvae at 50 g/L concentration and average consumed leaf area were 0.04 cm(2), 0.05 cm(2) and 0.30 cm(2) for H. lupulus, H. platytaenium and A. millefolium respectively. In dose response bioassay, it was revealed that there was a negative correlation between the averages consumed leaflet area and the plant extract dose. The greatest antifeedant activity was seen in H. lupulus extract treated leaflets at 10 g/L concentration and the average consumed leaflet area was 0.68 cm(2) after 72 h. The H. platytaenium and H. lupulus extracts had similar effects on the larval growth indices. Both plants extracts had 1.2 growth index values at 30 g/L concentration. These results indicate that the H. platytaenium and H. lupulus extracts could have significant potential as antifeedant and larval growth inhibition agent in the control of larvae of Colorado potato beetle.Öğe Antifeedant and stomach poison effects of different plant extracts to Spodoptera littoralis (Lepidoptera: Noctuidae)(ENTOMOLOGICAL SOC TURKEY, EGE UNIV, 2013) Karakoc, Omer Cem; Gokce, AyhanAntifeedant and stomach poison effects of 9 plant extracts were tested on Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae). Antifeedant effects of plant extracts varied from 22.44% to 68.96% and the most active plant extracts were Delphinium consolida (%68.96), Chrysanthemum segetum (62.67%), Artemisia vulgaris (61.09%) and Tanacetum mucroniferum (55.87%). Dose-response studies with the extracts showed that all extracts produced strong antifeedant effects ranging from 68.91% to 82.20% at 2 mg/cm(2) dose, D. consolida (48.92%) and T. mucroniferum (45.02%) also exhibited antifeedant properties at dose as low as 0.5 mg/cm(2). In stomach posion effects studies, C. segetum was the most toxic extract with %74.24 mortality. It was followed by D. consolida and T. mucroniferum with 70.53% and 67.04% mortality, respectively. Dose-mortality studies with C. segetum showed that it was the most toxic extract with 0.35 mg/cm(2) LC50 and 3.85 mg/cm(2) LC90 values.Öğe Demographic Analysis of Sex Ratio on Population Growth of Bactrocera dorsalis (Diptera: Tephritidae) With Discussion of Control Efficacy Using Male Annihilation(Oxford Univ Press Inc, 2016) Huang, Kevin Yu-Bing; Atlihan, Remzi; Gokce, Ayhan; Huang, Joyce Yu-Bing; Chi, HsinThe life table data for the oriental fruit fly, Bactrocera dorsalis (Hendel), at different adult sex ratios (1 female: 1 female, 1 female: 50 male, 50 female: 1 female free-choice mating, and 50 female: 1 male no-choice mating) were collected to determine the effects of sex-ratio manipulation on current pest control procedures. At 1 female: 1 male, females mated, on average, 2.3 times during their lifetime with a mean fecundity (F) of 1,122 eggs. The net reproductive rate (R-0), intrinsic rate of increase (r), finite rate (lambda), and mean generation time (T) were 561.0 offspring, 0.1693 d(-1), 1.1844 d(-1), and 37.4 d, respectively. At 50 female: 1 male free-choice mating, males mated 46.7 times during their lifetime, while at 50 female: 1 male no-choice mating, males mated on average 50 times during their lifetime, and all females mating only once in both treatments. The values for F, r, and lambda were significantly lower for both 50 female: 1 male treatments than those in the 1 female: 1 male group; the R-0 values, however, were either equal to or even higher than those in the 1?: 1? treatment. In the male-biased sex ratio (1 female: 50 male), fecundity was the highest (1,610 eggs) and female average life span the longest (166 d), while the R-0 was the lowest (31.6 offspring) among all treatments. Population projections showed that even at a sex ratio of 50 female: 1 male, B. dorsalis could still produce a large number of offspring. These findings demonstrate that management strategies for controlling B. dorsalis could be properly evaluated by using demographic methods. Because female annihilation appears to be a more effective control strategy, it should be considered as a viable alternative.Öğe Demographic features and population projection of resistant and susceptible populations of Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)(Springer, 2023) Naqqash, Muhammad Nadir; Gokce, Ayhan; Bakhsh, Allah; Salim, MuhammadColorado potato beetle (CPB) is the most devastating insect-pest of potato in America, Asia and Europe. Injudicious use of insecticides for management of this pest has resulted in resistance to all major groups of insecticides. Keeping in view the importance of inducing susceptibility in CPB management, fitness parameters of susceptible CPB population were calculated in comparison with normal field populations. For this purpose, Agria cultivar was used for rearing of Colorado potato beetle under controlled conditions. Susceptible popualtion was raised for more than 3 years before the study. While, field population was collected and F-2 was used for the life table study. The life table study of lab susceptible and field collected population showed that the lab susceptible population had significantly less intrinsic rate, fecundity, survival and other population parameters than the field collected population. The calculated population parameters for the field population were 0.12 day(-1) for the intrinsic rate of increase (r), 1.13 day(-1) for the finite rate of increase (lambda), and 71.07 offsprings/female for the net reproductive rate (R-0), and they were significantly higher than the parameters of lab susceptible population (r = 0.10 day(-1), lambda = 1.10 day(-1) and R-0 = 38.43 offsprings/female). The increased biotic potential of CPB in the field can be attributed to the widespread use of neonicotinoids like imidacloprid. After detailed study, such insecticides, that have tendency to enhance the biotic potential of insect-pests, can be banned for better management of notorious insect-pests like CPB.Öğe Demographic study of imidacloprid-resistant Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) fed on transgenic and commercial potato cultivars(Springer, 2022) Salim, Muhammad; Gokce, Ayhan; Bakhsh, AllahImpacts of transgenic and non-transgenic potato (Solanum tuberosum L.) plants containing more than one insecticidal gene on life table parameters of an imidacloprid-resistant Colorado potato beetle (CPB) colony, Leptinotarsa decemlineata, were studied under laboratory conditions. The life table parameters of the CPB colony on both commercial potato cultivars Agria and Lady Olympia and their transgenic counterparts were studied utilizing two methods: individually reared and group-reared to understand full potential of this destructive pest. All tested CPB larvae and adults on transgenic potato plants died before obtaining any results for the two-sex life table studies. The life table parameters were calculated using non-transgenic plants. The intrinsic rate of increase (r), the finite rate of increase (lambda), the net reproductive rate (R-0) and the mean generation time (T) were calculated 0.15 day(-1), 1.16 day(-1), 233.81 eggs/female and 37.43 days on Lady Olympia respectively. The CPBs, reared on cultivar Agria, had significantly lower values of r, lambda and R-0 except T (0.12 day(-1), 1.13 day(-1), 120.81 eggs/female and 39.75 days) respectively. The net reproductive rate (R-0) (204.31 eggs/female) and the mean generation time (T) 43.86 days of CPB were longer on Lady Olympia than on Agria when reared in groups. All these results indicate that the non-transgenic potato cultivar, Lady Olympia is a more susceptible host for CPB than the potato cultivar Agria and the transgenic potato cultivars exhibit significant toxicity and could be useful in control of imidacloprid-resistant CPB population.Öğe Demography and Mass-Rearing Harmonia dimidiata (Coleoptera: Coccinellidae) Using Aphis gossypii (Hemiptera: Aphididae) and Eggs of Bactrocera dorsalis (Diptera: Tephritidae)(Oxford Univ Press Inc, 2018) Yu, Jih-Zu; Chen, Bing Huei; Guncan, Ali; Atlihan, Remzi; Gokce, Ayhan; Smith, Cecil L.; Gumus, EbruWe compared rearing Harmonia dimidiata (F.) (Coleoptera: Coccinellidae) on four combinations of Aphis gossypii Glover (Hemiptera: Aphididae), and eggs of Bactrocera dorsalis Hendel (Diptera: Tephritidae), using the age-stage, two-sex life table. The four combinations were: both larvae and adults were reared on aphids; larvae were reared on aphids and adults were reared on fresh fruit fly eggs; larvae were reared on lyophilized fruit fly eggs and adults were reared on aphids; and larvae were reared on lyophilized eggs and adults were reared on fresh eggs. The highest intrinsic rate of increase (r = 0.1125 d(-1)) and net reproductive rate (R-0 = 260.7 offspring) were observed when both larval and adult stages of H. dimidiata were reared on A. gossypii. When B. dorsalis eggs were used as rearing media for larvae, adults, or both, the values of r and R-0 were significantly decreased. The lowest values (r = 0.0615 d-1 and R-0 = 38.6 offspring) were observed when both larvae and adults were reared entirely on B. dorsalis eggs. Despite the lower r and R-0 values, our results showed that B. dorsalis eggs could be considered as an adequate, less expensive alternative diet for rearing H. dimidiata because of the time and labor savings resulting from the ease of preparation and the ability to store the eggs for timely usage. The mass-rearing analysis showed that the most economical rearing system was to rear larvae on A. gossypii and adults on B. dorsalis eggs.Öğe Downregulation of imidacloprid resistant genes alters the biological parameters in Colorado potato beetle, Leptinotarsa decemlineata Say (chrysomelidae: Coleoptera)(Pergamon-Elsevier Science Ltd, 2020) Naqqash, Muhammad Nadir; Gokce, Ayhan; Aksoy, Emre; Bakhsh, AllahColorado potato beetle, Leptinotarsa decemlineata Say (coleoptera: chrysomelidae), is the important pest of potato all over the world. This insect pest is resistant to more than 50 active compounds belonging to various chemical groups. Potential of RNA interference (RNAi) was explored to knock down transcript levels of imidacloprid resistant genes in Colorado potato beetle (CPB) under laboratory conditions. Three important genes belonging to cuticular protein (CP), cytochrome P450 monoxygenases (P450) and glutathione synthetase (GSS) families encoding imidacloprid resistance were targeted. Feeding bioassays were conducted on various stages of imidacloprid resistant CPB lab population by applying HT115 expressing dsRNA on potato leaflets. Survival rate of insects exposed to CP-dsRNA decreased to 4.23%, 1532% and 47.35% in 2nd, 3rd and 4th instar larvae respectively. Larval weight and pre-adult duration were also affected due to dsRNAs feeding. Synergism of RNAi with imidacloprid conducted on the 2nd instar larvae, exhibited 100% mortality of larvae when subjected to reduced doses of GSS and CP dsRNAs along with imidacloprid. Utilization of three different dsRNAs against imidacloprid resistant CPB population reveal that dsRNAs targeting CP, P450 and GSS enzymes could be useful tool in management of imidacloprid resistant CPB populations. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Evaluation of tea tree oil formulations contact and stomach toxicity against the Egyptian cotton leafworm, Spodoptera littoralis (Boisduval, 1883) (Lepidoptera: Noctuidae)(Tubitak Scientific & Technological Research Council Turkey, 2022) Simsek, Seyda; Gokce, Ayhan; Hassan, ErrolThe insecticidal potential of tea tree oil formulations was tested for contact and stomach poison toxicities against various stages of the Spodoptera littoralis ((Boisduval, 1883) (Lepidoptera: Noctuidae) larvae under laboratory conditions. The study was carried out at Yozgat Bozok University Faculty of Agriculture between 2020 and 2021. In the contact toxicity test, the formulations were tested at different stages of larvae by topical application. Among the tested formulations, TTO (100%), F14 (91.72%), and F15 (89.20%) formulations caused the highest mortality in the S. littoralis 3rd stage larvae after 72 h. Dose-response bioassay with the most promising formulations (TTO, F14 and F15) revealed that LD50 values were 0.016, 0.046, and 0.076 mu g/larvae for TTO, F14, and F15, respectively. The stomach poison effects of the formulations were tested by applying a 0.16 mu g/cm2 dose to lettuce leaf discs. The F17 and F18 formulations produced the highest mortality with mortality rates of 75% and 65% after 10 days of incubation, respectively. The calculated LC50 values for these formulations were 0.027 and 0.042 mu g/cm2 for F17 and F18 formulations after 10 days of incubation, respectively. These results revealed that tea tree oil and its main components containing formulations have the potential in controlling this destructive lepidopteran pest species.Öğe Exploring the efficacy of RNAi-mediated gene knock-down via oral delivery of dsRNA in the Colorado potato beetle (Leptinotarsa decemlineata Say)(Tubitak Scientific & Technological Research Council Turkey, 2023) Tariq, Haneef; Gokce, Ayhan; Aksoy, Emre; Elci, Eminur; Bakhsh, AllahRNA interference (RNAi) is a versatile genetic tool capable of selectively inhibiting the expression of any gene in a targeted organism. Its implementation holds great promise for safeguarding crops against insect pests and diseases. Vacuolar-ATPase represents an ideal target for RNAi-based pest management strategies since it is an enzyme essential for various physiological processes in insects. In this study, double-stranded RNA (dsRNA) was synthesized using an L4440 vector in Escherichia coli HT115 strain to silence the Vacuolar-ATPase proteolipid subunit mRNA in the Colorado potato beetle (Leptinotarsa decemlineata Say). To assess the effectiveness of RNAi, L. decemlineata larvae at different developmental stages were fed potato leaflets treated with dsRNA. The feeding bioassays using dsV-ATPase resulted in significant mortality rates, ranging from 45% to 77% across all of the instar stages of L. decemlineata. Furthermore, ingestion of dsRNAs by third-and fourth-instar larvae exerted significant effects on their body weight and foliage consumption. Notably, feeding the larvae dsV-ATPase led to a significant reduction in V-ATPase gene expression, confirming the efficacy of RNAi-mediated gene silencing in controlling L. decemlineata populations. These findings highlight the potential of RNAi-mediated gene silencing as a valuable strategy for managing L. decemlineata populations by targeting essential genes.Öğe Fast Population Growth in Physogastry Reproduction of Luciaphorus perniciosus (Acari: Pygmephoridae) at Different Temperatures(Oxford Univ Press Inc, 2017) Bussaman, Prapassorn; Sa-uth, Chirayu; Chandrapatya, Angsumarn; Atlihan, Remzi; Gokce, Ayhan; Saska, Pavel; Chi, HsinLuciaphorus perniciosus Rack is one of the most serious pests of several cultivated mushroom species including Ganoderma lucidum (Fr.), Flammulina velutipes Karst., Auricularia polytricha (Mont.) Saac., Lentinus polychrous Lev., and Lentinus squarrosulus (Mont.) Singer in Thailand. Adult female Lu. perniciosus produce offspring inside their physogastric hysterosomas, with all embryos developing through to the adult stage while remaining in the abdomen. Once the abdomen ruptures, the female parent dies and the offspring consisting of mostly fertilized female adults along with a few male adults continue to emerge from the cadaver of the mother for a period of several days. This peculiar type of reproduction after the death of the mother is a special case for life table analysis and has not been discussed previously in demographic analyses. In this study, the life table data of this mite fed on Le. squarrosulus were collected at 25, 30, and 35 degrees C and analyzed by using the agestage, two-sex life table. The standard errors of population parameters were estimated by using the bootstrap technique (200,000 bootstraps). At 25, 30, and 35 degrees C, females started reproduction at ages 9, 5, and 3 d, respectively; the net reproductive rates (R-0) were 192.27, 253.81, and 234.11 offspring. Due to their rapid development and high fecundity, the r values were as high as 0.4189, 0.8653, and 1.0892 d (1) at 25, 30, and 35 degrees C, respectively. Computer projection indicated that the mushroom mites Lu. perniciosus is capable of a threefold daily increase at 35 degrees C.Öğe Fumigant toxicity of some plant essential oils to Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae)(ENTOMOLOGICAL SOC TURKEY, EGE UNIV, 2015) Selimoglu, Tugba; Gokce, Ayhan; Yanar, DurdaneThe fumigant toxicity of five plant essential oils (Foeniculum vulgare Miller, Lavandula stoechas L., Thymbra spicata L., Teucrium polium L. and Heracleum platytaenium Boiss.) were tested on Acanthoscelides obtectus (Say) (Col.: Bruchidae) under laboratory conditions. Single dose (100 mu l/L) of plant essential oils were initially tested on adult stage of A. obtectus. The greatest fumigant toxicity against A. obtectus was seen with F. vulgare essential oil, followed by T. spicata and L. stoechas essential oils. In the dose response bioassays with F. vulgare, T. spicata and L. stoechas, the calculated LC50 values were 22,3 mu l/L, 32,4 mu l/L and 46,3 mu l/L respectively. The main components of plant essential oils of three plants showing high response were determined by GC-MS analysis. F. vulgare essential oil's main components were anisole (79%) and L-Fenchone (13%). T. spicata and L. stoechas contain L-Fenchone (55%, 57%), Camphor (24%, 24%) and Eucalyptol (13%, 13%) respectively. Main components L-Fenchone and Camphor caused about 100% mortality at 80 mu l/L dose in 48 hours. The results indicate that F. vulgare essential oil or its components may have a potential in controlling of A. obtectus.Öğe Harnessing plant-mediated RNAi for effective management of Phthorimaea absoluta by targeting AChE1 and SEC23 genes(Elsevier, 2024) Hashmi, Muneeb Hassan; Tariq, Haneef; Saeed, Faisal; Demirel, Ufuk; Gokce, Ayhan; Merzendorfer, Hans; Aksoy, EmreTomato production on a global scale is under persistent pressure due to the devastating impact of Phthorimaea absoluta Meyrick (Lepidoptera: Gelechiidae), the South American tomato leaf miner. To combat this devastating pest, we explored the potential of plant-mediated RNA interference (RNAi) as a novel strategy for its management. Using transgenic techniques, we developed RNAi constructs (p35SÖğe Heterologous expression of distinct insecticidal genes in potato cultivars encodes resistance against potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)(Springer Heidelberg, 2024) Salim, Muhammad; Bakhsh, Allah; Naqqash, Muhammad Nadir; Gokce, AyhanThe potato tuber moth, Phthorimaea operculella (Zeller), is a notorious insect pest of potato incurring substantial yield losses in the field as well as in storage. Chemical control is difficult to exercise due to the latent feeding of the caterpillars and their ability to develop resistance against insecticides. One of the essential components of efficient insect-resistant management is using two or more different insecticidal genes in transgenic crops to effectively avoid and delay the resistance development in insect pests. Two constructs, namely DS-1 (cry3A + SN-19 genes) and DS-2 (OCII + SN-19 genes) in pCAMBIA1301 binary vector, were developed and were transformed in potato cultivars (Agria and Lady Olympia) via Agrobacterium-mediated transformation. The molecular analysis confirmed gene integration and expression of the introduced genes in transgenic plants. The insecticidal effects of incorporated genes in transgenic plants were assessed against 1st, 2nd, 3rd, and 4th instar potato tuber moth (PTM) larvae. The transgenic plants endured significantly high mortalities (100%) of larval stages of PTM within 72 h. Our results show that these transgenic potato plants have the potential to control populations of PTM and are also useful tools in managing PTM that would ultimately reduce the dependency on conventional chemical pesticides with potentially less or minimal hazards. These lines can also serve as an excellent source of germplasm for potato breeding program.Öğe Insecticide resistance and its molecular basis in urban insect pests(SPRINGER, 2016) Naqqash, Muhammad Nadir; Gokce, Ayhan; Bakhsh, Allah; Salim, MuhammadInsecticide resistance is one of the most important evolutionary phenomena for researchers. Overuse of chemicals has induced resistance in insect pests that ultimately has led to the collapse of disease control programs in many countries. The erroneous and inappropriate management of insect vectors has resulted in dissemination of many vector-borne diseases like dengue, malaria, diarrhea, leishmaniasis, and many others. In most cases, the emergence of new diseases and the revival of old ones can be related with ecological changes that have favored rapid growth of vector densities. Understanding molecular mechanisms in resistant strains can assist in the development of management programs to control the development and spread of resistant insect populations. The dominant, recessive, and co-dominant forms of genes encoding resistance can be investigated, and furthermore, resistance development can be addressed either by the release of susceptible strains or timely insecticide rotation. The present review discusses the resistance level in all important insect vectors of human diseases; the molecular basis of evolvement of resistance has also been discussed.Öğe Insights into the Use of Eco-Friendly Synergists in Resistance Management of Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)(Mdpi, 2022) Ullah, Rana Muhammad Kaleem; Gokce, Ayhan; Bakhsh, Allah; Salim, Muhammad; Wu, Hai Yan; Naqqash, Muhammad NadirSimple Summary The discovery of insecticides requires time and has a high investment cost. However, injudicious use of insecticides has resulted in insect pest resistance and pest resurgence. These factors limit the market life of insecticides. To cope with this problem, synergists working as blockers of detoxification enzymes can provide a unique solution in resistance management. Owing to problems associated with chemical synergists, plant-based and RNAi-based synergists are much safer and easier to develop against insects. In fact, the Colorado potato beetle (CPB) has a unique detoxification mechanism due to its co-evolution with Solanaceous plants. This review is about how synergists can be used to deal with the resistance management of the CPB and will be helpful for researchers devising unique pest management strategies for other insect pests. The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), is the most notorious insect pest of potato globally. Injudicious use of insecticides for management of this pest has resulted in resistance to all major groups of insecticides along with many human, animal health, and environmental concerns. Additionally, the input cost of insecticide development/discovery is markedly increasing because each year thousands of chemicals are produced and tested for their insecticidal properties, requiring billions of dollars. For the management of resistance in insect pests, synergists can play a pivotal role by reducing the application dose of most insecticides. These eco-friendly synergists can be classified into two types: plant-based synergists and RNAi-based synergists. The use of plant-based and RNAi-based synergists in resistance management of insect pests can give promising results with lesser environmental side effects. This review summarizes the resistance status of CPB and discusses the potential advantage of plant-based and RNAi-based synergists for CPB resistance management. It will motivate researchers to further investigate the techniques of using plant- and RNAi-based synergists in combination with insecticides.Öğe Life table study of Sitotroga cerealella on different cereals and its implications on the performance of the egg parasitoid (Trichogramma chilonis) under laboratory conditions(Nature Portfolio, 2023) Salim, Muhammad; Ullah, Imdad; Saljoqi, Ahmad Ur Rahman; Gokce, Ayhan; Ahmad, Sarir; Almutairi, Mikhlid H.; Sayed, Amany A.Sitotroga cerealella is one of the major pests of cereals in the field and storage conditions throughout the world. The main objective was to study the life tables of S. cerealella on wheat, maize and barley and its implications on percent parasitism of Trichogramma chilonis. S. cerealella is reared under lab conditions as its eggs are utilized for rearing T. chilonis. Fresh eggs of S. cerealella were collected and after hatching the neonate larvae of S. cerealella were transferred onto each host plant species for obtaining first (F1) generation (G). Seventy eggs were used for each host and each egg was used as a replicate. Daily observations were made for recording the life-table parameters of the S. cerealella. The data showed that the developmental time of S. cerealella eggs and pupae was maximum (5.68 and 7.75 days) when reared on wheat, while the maximum larval duration (19.77 days) of S. cerealella was recorded on barley. The maximum fecundity (290.30 & PLUSMN; 22.47 eggs/female) was recorded on maize, while minimum fecundity per female was recorded on barley (159.30 eggs/ female). The S. cerealella reared on maize had significantly higher values of finite rate of increase (& lambda;), intrinsic rate of increase (r), and net reproductive rate (R-o) (0.14 & PLUSMN; 0.04 day(- 1), 1.16 & PLUSMN; 0.05 day(- 1), and 136.85 & PLUSMN; 20.25 eggs/ female) respectively. The mean generation time (T) (35.18 & PLUSMN; 0.61 days) was higher on wheat. Likewise, the gross reproductive rate (GRR) and the age-stage specific reproductive values (v(xj)) of newly oviposited eggs of S. cerealella were recorded higher (136.85 & PLUSMN; 20.25; 1.160 offspring) on maize. The data regarding the efficacy of T. chilonis for different parameters were recorded higher on maize i.e., percent parasitism (89.00 & PLUSMN; 2.30%), percent adult emergence (81.60 & PLUSMN; 1.20%), adult longevity (3.80 & PLUSMN; 0.10 days) and total adult longevity (9.90 & PLUSMN; 0.20 days) as compared to wheat and barley. Our findings revealed that S. cerealella can be best reared on maize under laboratory conditions as it prefers this host as compared to wheat and barley. Therefore, assigning the most susceptible and favorite host (maize) would help us to improve T. chilonis mass production under laboratory conditions.Öğe Stacked insecticidal genes in potatoes exhibit enhanced toxicity against Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)(Springer, 2021) Salim, Muhammad; Bakhsh, Allah; Gokce, AyhanThe present study was performed to express stacked insecticidal genes in potato cv. Lady Olympia and Agria to encode resistance against Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say). Bacillus thuringiensis (Bt) gene (cry3A), synthetic hybrid (SN-19) and plant proteinase inhibitor Oryza cystatin II (OCII) cloned in pCAMBIA1301 binary vector in two different combinations as of DS-1 (cry3A + SN-19 genes) and DS-2 (OCII + SN-19 genes) constructs and further transformed to two potato cultivars using Agrobacterium-mediated transformation. All molecular analyses confirmed gene integration and expression in a total of 27 primary transformants in both Agria and Lady Olympia. Insecticidal effects of T0 progeny transgenic potato plants were tested against CPB under laboratory conditions. Transgenic plants of Agria and Lady Olympia transformed with DS-1 and DS-2 constructs caused 100% mortality to all larval stages and adults of CPB. However, 100% mortality of tested insects took a longer time in the adult stage (10-14 days) compared to larval stages (2-6 days). Foliage consumption by L2-L4 larval stages and adults of CPB was significantly reduced in Agria and Lady Olympia plants transformed with DS-1 and DS-2 constructs, as compared to their control plants. Lower foliage consumption of transgenic plants by L1 larval stages was also observed, but the reduction was only statistically significant for some of the tested plants. These promising results indicate that the transgenic potato plants exhibit a high potential in controlling CPB population and are a useful tool in the management of imidacloprid-resistant CPB.Öğe The Insecticide Resistance Allele kdr-his has a Fitness Cost in the Absence of Insecticide Exposure(Oxford Univ Press Inc, 2018) Chi, Hsin; You, Minsheng; Atlihan, Remzi; Kavousi, Aurang; Ozgokce, Mehmet Salih; Tuan, Shu-Jen; Gokce, Ayhan[Abstract Not Available]Öğe Toxicological and behavioral effects of some plant extract on Colorado potato beetle, Leptinotarsa decemlineata Say, 1824 (Coleoptera: Chrysomelidae)(Entomological Soc Turkey, Ege Univ, 2017) Alkan, Mustafa; Gokce, AyhanRepellent, ovicidal and oviposition deterrent effects of six plant extracts [Heracleum platytaenium Boiss (Apiaceae), Humulus lupulus L. (Cannabaceae), Achillea millefolium L. (Asteraceae), Acanthus dioscoridis L. (Acanthaceae), Phlomoides tuberosa (L.) Moench (Lamiaceae), Bifora radians Bieb. (Apiaceae)] were tested on Leptinotarsa decemlineata Say, 1824 (Coleoptera: Chrysomelidae) under laboratory conditions. Methanol extracts prepared from plant vegetative components were tested on L. decemlineata. Heracleum platytaenium extract was significantly more toxic against the egg stage than all other extracts, except for A. millefolium 5 d after treatment. It was followed by A. millefolium extract reducing the egg hatch rate to 15%. Significant mortality was not observed in the case of other plant extracts. In the second series of experiments, different dose-response bioassays with H. platytaenium against L. decemlineata eggs were conducted. The lowest egg hatch rate of 1% was observed at 7.5% [w/v (plant extract/acetone]. The greatest oviposition deterrent effect was seen with the H. platytaenium extract treatment, which resulted in no egg laying. Plant extracts showed a high level of repellent activity to L. decemlineata and their activity increased with extended incubation time. The greatest repellency was observed with the A. millefolium extract treatment, which gave 0.01% repellency in the first 15 min. These results show that H. platytaenium extract could be a useful toll in the control of L. decemlineata.
