Late 3rd Instar Larvae Research Articles

Evaluation of indigenous plants' extracts for mosquitocidal activity against different stages of Culex quinquefasciatus say (Diptera: Culicidae).

Being vector of West Nile Virus and falariasis the control of Culex quinquefasciatus is likely to be essential. Synthetic insecticide treatment is looking most effective for vectors mosquito control. However, these products are toxic to the environment and non-target organisms. Consequently, ecofriendly control of vectors mosquito is needed. In this regard botanical insecticide is looking more fruitful. Therefore, the present research aimed to investigate the effectiveness of methanolic extract and various fractions, including, n-hexane, ethyl-acetate, chloroform, and aqueous fraction, obtained from methanolic extract of Ailanthus altissima, Artemisia scoparia, and Justicia adhatoda using separating funnel against larval, pupal, and adult stages of Culex quinquefasciatus. The larvae and pupae of Culex quinquefasciatus were exposed to various concentrations (31.25-1000 ppm) of methanolic extract and its fractions for 24 hours of exposure period. For knock-down bioassay (filter paper impregnation bioassay) different concentration of the methanolic extract and its various fractions (i.e. 0.0625, 0.125, 0.25, 0.5 and 1mg/mL) were applied for 1 hour exposure period. The results were statistically analysed using standard deviation, probit analysis, and linear regression. The R2 values of larvae, pupae, and adult range from 0.4 to 0.99. The values of LC50 (concentration causing 50% mortality) for late 3rd instar larvae after 24 hours exposure period range from 93-1856.7 ppm, while LC90 values range from 424 -7635.5ppm. The values of LC50for pupae range form 1326.7-6818.4ppm and and values of LC90 range from 3667.3-17427.9ppm, respectively. The KDT50 range from 0.30 to 2.8% and KDT90 values range from1.2 to 110.8%, respectively. In conclusion, Justicia adhatoda may be effective for controlling populations of vector mosquito.

Efficacy of Chlorpyrifos and Bacillus Thuranginsis Israelinsis against Culex Pipiens (L.)

Culex pipiens (L.) (Diptera: Culicidae) is the most important medical insect in many parts of the world. Biological and natural chemicals have many advantages over the traditional ones in case of mosquito control. The efficacy of two insecticides belonging to different groups chlorpyrifos-ethyle (oranophosphate) and Bacillus thuranginsis var israelinsis) (bio-insecticides)were evaluated against the field and laboratory individuals of late 3rd instar larvae of Culex pipiens at different concentrations and three periods of exposure under laboratory conditions. Results obtained showed that the laboratory strain showed higher susceptibility to the tested insecticides than the mosquito populations collected from Abo-Rewash City, Giza Governorate and the mortality percentage was increased gradually with increasing the insecticide concentrations and the mortality percentage showed significant differences between concentrations and control. Also, The activity of acetyl cholinesterase (AChE), the glutathione S- transferase (GST), Total proteins and the activities of both Aspartate aminotransferase AST(GOT) and Alanine aminotransferase ALT(GPT) were determined were determined after 72 hrs of insecticidal exposure.

Bioefficacy of Lemongrass and Tea Tree Essential Oils Against House Fly, Musca domestica.

The management of house fly, Musca domestica has become immensely important to prevent epidemics of many detrimental diseases. In view of this objective, the present study demonstrates the efficacy of lemongrass (LG) and tea tree essential oils (TTEOs) against M. domestica. The TTEO proved to be more lethal against larvae and adults of M. domestica depicting an LC50 at 14.88 mg/ dm3 which was 17.19 mg/ dm3 for LGEO. In contrast, pupicidal effect of LGEO was much higher (LD50, 14.49 µl/0.25L) as compared to TTEO. The LGEO drastically reduced the total body sugar, glycogen and protein contents by 3.29, 2.95 and 7.56 fold, respectively, contrasting with high influence of TTEO on lipid content of the late 3rd instar larvae. A considerable reduction in gut enzymes secretion was observed due to treatment of EOs thereby altering gut physiology of the insect. Moreover, significant inhibition of acetylcholine esterase (AchE) was also observed with LGEO at LC50 concentration (5.33 mg/ml) inhibiting insect neurotransmission. The gas chromatography-mass spectrometric (GC-MS) analysis of the LGEO showed 12 major compounds dominated by Citral whereas TTEO contained only 5 major compounds. Further analysis by field emission scanning electron microscopy (FESEM) revealed distortion and shrinkage of larval bodies caused by the treatment of EOs. These overall observations brand LG and TT-EOs as potential organic-insecticides against M. domestica.Graphic Supplementary InformationThe online version of this article (10.1007/s40011-020-01220-z) contains supplementary material, which is available to authorized users.

Evaluation of Two Different Solvents for Azolla pinnata Extracts on Chemical Compositions and Larvicidal Activity against Aedes albopictus (Diptera: Culicidae)

Limited success for Aedes control program has impelled the necessities for new insecticide search. Hence, alternative plant compounds may be competent to overcome the pesticide resistance problem and to lead a chemical-free environment. Following go-green conceptions, larvicidal effects of the Azolla pinnata extracts using methanol and acetone solvent against Aedes albopictus late 3rd instar larvae were evaluated. The A. pinnata fresh plant from Kuala Krai, Kelantan, Malaysia (5° 31′ N 102° 12′ E) was used for crude extraction with Soxhlet apparatus using methanol and acetone solvents. Next, larvicidal test following WHO guidelines was tested against late 3rd instar to early 4th instar larvae of Ae. albopictus mosquitoes. Meanwhile, the chemical composition of extracts and their structures have been identified using GCMS-QP2010 Ultra (Shimadzu) fitted with Rtx-5MS capillary column (30 m × 0.25 mm inner diameter, ×0.25 μm film thickness; maximum temperature, 370°C), coupled to QP2010 Ultra (Shimadzu) MS. Results of methanol solvent showed the highest larvicidal activity against late 3rd instar to early 4th instar Ae. albopictus larvae with LC50 and LC95 values of 867 ppm and 1293 ppm at 24 hours, respectively, and 647 ppm and 972 ppm at 48 hours, respectively. Meanwhile, acetone solvent compounds were recorded with LC50 and LC95 values of 1072 ppm and 1302 ppm at 24 hours, respectively, and 904 ppm and 1126 ppm at 48 hours, respectively. Finally, the chemical composition of A. pinnata plant extracts has been characterized for 35 active compounds from methanol solvent and 37 active compounds with acetone solvent. In conclusion, A. pinnata plant bioactive molecules are efficient and could be developed as an eco-friendly, “go-green” approach for mosquitoes' larvicidal control programs. Thus, our study suggests that future research can be conducted on A. pinnata bioactive ingredients against Ae. albopictus larvae in small-scale field trials as botanical insecticide for environmentally friendly approach.

Mosquito larvicidal activity of Rauvolfia serpentina L. seeds against Culex quinquefasciatus Say

Objective To establish the larvicidal activities, if any of solvent extracts of Rauvolfia serpentina (R. serpentina) L. seeds against Culex quinquefasciatus (Cx. quinquefasciatus) Say, 1823 as target species. Methods Seeds of R. serpentina were extracted with five solvents graded according to the polarity [viz. petroleum ether, benzene, ethyl acetate, acetone and absolute alcohol] continuing one after another with the same seeds. Results Mortality rate with petroleum ether extract was significantly higher than other extracts. The mortality rates of late 3rd instar larvae were 50.33±5.51, 10.00±1.00, 0.00±0.00, 21.33±1.53 and 0.00±0.00 in 100 ppm concentration of petroleum ether, benzene, ethyl acetate, acetone and absolute alcohol respectively, after 24 h of exposure period. Conclusions Results of this study show that petroleum ether extract of R. serpentina seed may be considered as a potent source of mosquito larvicidal agent.

Blow flies (Diptera: Calliphoridae) survive burial: Evidence of ascending vertical dispersal

This study was undertaken to determine if immature blow flies could complete development following burial and emerge from the soil as adults. Two species of blow flies, Cochliomyia macellaria and Protophormia terraenovae, were placed at three depths and at three different life stages, in a simulated burial to evaluate the impact of soil on ascending vertical dispersal and fly survival. In soil columns, immature stages of each species were covered with 5, 25 and 50cm of soil. Emerging adult flies of both species reached the surface from all depths at all three immature stages (2nd instar, 3rd instar and pupae). At the 50-cm depth, flies were least successful in reaching the surface when buried as pupae and most successful as late 3rd instar larvae (prepupae). Collectively, more adult flies emerged from the soil if buried as 3rd instars (79.6%) than either 2nd instars or pupae (59.6% and 59.3%, respectively (F(2,159)=14.76, P<0.0001)). Similarly, at shallow burial depths of 5 and 25cm, 75.6% and 70.4% of the adults successfully reached the surface, compared with 52.6% at the 50-cm depth (F(2,159)=15.95, P<0.0001). Second instars demonstrated ascending vertical dispersal behaviours in the soil column by pupating closer to the surface. Nearly half (46.6%) of the C. macellaria 2nd instars buried in 25cm of soil pupated nearer to the surface. Similarly, 45.4% of the P. terraenovae 2nd instars pupated nearer to the surface. When buried at 50cm, approximately 25% of 2nd instars of both species pupated nearer to the surface. When 3rd instars of C. macellaria and P. terraenovae were buried at 120cm, 40% and 4.3% of the adults, respectively, successfully reached the soil surface.

고구마 재배지 주요 굼벵이 발생양상 및 피해

고구마 재배지에 발생하는 풍뎅이류 유충(굼벵이)의 종류 및 종별 피해양상을 조사하였다. 고구마 재배지 토양에 발생하는 풍뎅이류는 큰검정풍뎅이(Holotrichia parallela), 참검정풍뎅이(Holotrichia diomphalia), 애풍뎅이(Anomala rufocuprea) 3종이지만 주로 발생하는 풍뎅이류는 대부분 큰검정풍뎅이로 조사되었다. 굼벵이류에 의한 고구마 괴근 피해율은 지역에 따라 차이가 있었는데 평군 2-40%였고, 심한 경우는 80% 이상의 피해를 나타낸 포장도 있었다. 큰검정풍뎅이는 10월 하순부터 다음해 6월 하순까지 토양 속에서 3령의 노령유충으로 월동하였으며, 월동기간 동안 유충의 생존율은 92%로 매우 높았다. 고구마 포장에서 큰검정풍뎅이 유충은 7월 하순부터 8월 중순 사이에 발생하기 시작하였고, 고구마의 굼벵이 피해는 8월 하순부터 나타나기 시작하여 수확기까지 지속되었다. This experiment was conducted to investigate population dynamics of white grubs and its damages in sweet potato fields. There were three species of white grubs that fed on the roots of sweet potato in Honam area. Among them, Holofrichia parallela was a major insect pest. Damage rate of sweet potato by white grubs were about 2 to 40% differed with regions. In some region where it was severe the damage rate of sweet potato was about 80% or more. H. parallela overwintered as a late 3rd instar larvae in soil from late October to late-June, and the survival rate of them was 92%. The occurrence pattern of H. parallela larvae varied in different seasons. In sweet potato field, H. parallela larvae populations started being observed during late-July to mid.-August. The damage by the grub began to occur late-August in field and lasted to the harvest time.

Larval anatomy and structure of absorbing epithelia in the aphid parasitoid Aphidius ervi Haliday (Hymenoptera, Braconidae)

The present work describes Aphidius ervi Haliday (Hymenoptera, Braconidae) larval anatomy and development, focusing on time-related changes of body structure and cell ultrastructure, especially of the epithelial layers involved in nutrient absorption. Newly hatched 1st instar larvae of A. ervi are characterised by gut absence and a compact cluster of cells makes up their body. As the parasitoid larva develops, the central undifferentiated cell mass becomes hollowed out, leading to the formation of gut anlage. This suggests that absorption of nutrients at that stage may take place through the body surface, as more directly demonstrated by the occurrence on the epidermis of proteins associated with transepithelial transport, such as Na +/K +-ATPase and alkaline phosphatase (ALP). Second instar larvae show the presence of the gut with a well-differentiated brush border and a peritrophic membrane. Gut cells are filled by masses of glycogen granules and lipid droplets. The tracheal system starts to be visible. The haemocoel becomes evident in late 2nd instar, and contains large silk glands. Mature 3rd instar larvae are typically hymenopteriform. The midgut accounts for most of the body volume and is actively involved in nutrient absorption, as indicated by the well developed brush border and by the presence of Na +/K +-ATPase and ALP on the basolateral and luminal membrane respectively. At this stage, large lipid droplets have gradually replaced the cellular glycogen stores in the midgut cells. The tracheae are completely differentiated, but their internal lumen still contains fibrillar material, suggesting that they are not functional as long as host fluids bath the parasitoid larva. In late 3rd instar larvae, silk glands, structurally similar to Malpighian tubules, show a very intense vesicular traffic toward the internal lumen, which, eventually, results in being filled by secretion products, suggesting the possible recycling of metabolic waste products during mummy formation.

Developmental changes in dopamine levels in larvae of the fly Chymomyza costata: comparison between wild-type and mutant-nondiapause strains

Dopamine and two related catecholamines, L-3,4-dihydroxyphenylalanine (DOPA) and N-acetyl dopamine (NADA), were analyzed in whole body and tissue samples taken throughout late larval development of the drosophilid fly Chymomyza costata, which enters facultative diapause as a mature 3rd instar larva in response to short photophase. Wild-type ( W) and mutant-nondiapause ( M) strains reared under diapause inducing ( d) and preventing ( nd) photophases were compared. Developmental changes in the whole body of dopamine levels showed some general features irrespective of fly strain and rearing conditions: sharp major peaks during moult from second to third instar larva and during pupariation; lower minor peaks around the middle of both 2nd and 3rd instars. Significant differences between the strains and conditions were also found: dopamine levels were lower throughout the 2nd instar and during the 2nd to 3rd instar moult of mutant strain larvae ( M/d) as compared to wild-type larvae ( W/nd and W/d); while the late 2nd and late 3rd instar larvae destined to diapause ( W/d) maintained relatively high dopamine concentrations, their counterparts destined to continuous development ( W/nd and M/d) significantly decreased dopamine levels prior to the 2nd to 3rd instar moult or pupariation. Possible relationship between the dopamine levels and diapause induction/onset in C. costata larvae is discussed. Integument contained more than 90% of the dopamine found in the whole body. The gut and central nervous tissues showed relatively low pools of dopamine, only trace amounts were detected in haemolymph and no dopamine was found in fat body. DOPA levels were low and stable throughout larval development of both W and M strains and under both conditions. NADA levels peaked during second halves of 2nd and 3rd instars of both strains, then dropped to trace levels and were elevated again during 2nd to 3rd instar moult as well as in tanned prepupae. No elevation of NADA levels was recorded in 3rd instar W/d larvae which entered diapause.

Enhancing Effects of Supernatants from Various Cultures of Bacillus thuringiensis on Larvicidal Activity of &amp;delta;-Endotoxin against the Common Cutworm, Spodoptera litura

The synergistic effects of supernatants from cultures of nine strains of Bacillus thuringiensis toward the insecticidal activity of δ-endotoxin were investigated using neonates of the common cutworm, Spodoptera litura, and late 3rd instar larvae of the diamondback moth, Plutella xylostella by the diet incorporation method. Synergistic effects between supernatants and δ-endotoxins were detected against S. litura but not toward P. xylostella. Synergistic activity in supernatants against S. litura but not toward P. xylostella. Synergistic activity in supernatants against S. litura was observed in four strains and the occurrence was shown to be dependent on culture media. Interestingly, B. thuringiensis serovar japonensis strain Buibui and B. thuringinensis serovar morrisoni strain san diego, which produce insecticidal crystal proteins specific only to coleopteran larvae, were shown to produce synergistic factor(s) in culture supernatants. The synergistic substance(s) released into supernatants from various strains of B. thuringiensis were apparently the same.

Mosquito Larvicidal and Ovipositional Activity of Descurainia Sophia Extract

The ethanolic extract (ee) of the herb descurainia sophia (l.) webb was tested for its activity against the mosquito cu/ex quinquefasciatus say. the treatment of the late 3rd instar larvae with 100-1500 ppm of the ee resulted in concentration-dependent larval mortality and inhibition of emergence. the gravid females of c. quinquefasciatus deposited higher number of egg rafts in water treated with 1-50 ppm of ee than the nontreated water or 100 ppm of/), sophia (ee). at 1-100 ppm of ee, d. sophia induced ovicidal activity against zero h old eggs and substantial mortality against newly hatched larvae.

A novel set of heat shock polypeptides in malpighian tubules ofDrosophila melanogaster

In contrast to the general notion of induction of a common set of heat shock polypeptides (HSP) in all cell types, heat shocked malpighian tubules (MT) ofDrosophila melanogaster larvae did not synthesize the common set of HSP induced in salivary glands or brain ganglia of larvae and in gonads (testis or ovary) of adult flies. Instead, heat shocked MT of late 3rd instar larvae and freshly eclosed adults synthesized a novel set of polypeptides (MT-specific HSP) with a major induced band at 58 kd. Surprisingly, the MT of older flies synthesized both the MT-specific as well as the common set of HSP in response to heat shock. Fusion genes with hsp70 or hsp26 promoter linked to the lac-Z (beta galactosidase) or to ADH (alcohol dehydrogenase) reporter gene were also not induced in larval MT but showed good induction in the MT of older flies. This unexpected finding raises intriguing issues regarding the nature of MT-specific HSP, their genes and the cell type dependent induction of the two sets of HSP.

Ecdysteroid synthesis by the ring gland of Drosophila melanogaster during late-larval, prepupal and pupal development

Radioimmunoassay has been used to determine the characteristics of ecdysteroid synthesis by ring glands and brain-ring gland preparations from late 3rd-instar larvae of Drosophila melanogaster cultured in vitro. The rate of synthesis and secretion is linear for at least 4 hr in culture. Using a 4-hr culture period, variation in the rate of ecdysteroid synthesis by brain-ring gland preparations during larval, prepupal and pupal development has been examined. The rate of synthesis and secretion is highest in late 3rd-instar larvae and decreases after puparium formation. During pupal development, at a time when the endogenous ecdysteroid titre is again increasing, the rate of ecdysteroid synthesis by brain-ring gland preparations remains low and is only 10% of that prior to puparium formation. It is, therefore, likely that the ring gland is not a major source of ecdysteroids during this period.

Influence of oxygen concentration on development ofDrosophila melanogaster

1st, 2nd, and early 3rd instarDrosophila larvae are extremely sensitive to 100% O2 or 75% O2/25% N2 (at atmospheric pressure) whereas eggs, late 3rd instar larvae, and pupae are relatively insensitive under our exposure conditions. Eclosing flies exposed to an O2 enriched environment consistently possessed 2 eye abnormalities: dark eye color and altered eye shape.

Specific activation of puff 93D of Drosophila melanogaster by benzamide and the effect of benzamide treatment on the heat shock induced puffing activity.

A 10 or 20 min in vitro treatment of salivary glands of late 3rd instar larvae of Drosophila melanogaster with 1 mg/ml benzamide (BM) at 24 degrees C results in the specific induction of the 93D puff and at the same time all other chromosomal RNA synthesis is severely repressed. Incorporation of 3H-uridine in the nucleolus is not affected. In glands heat shocked (37 degrees C) for 20 min in presence of BM, all the temperature shock (TS) puffs are induced but they incorporate 3H-uridine to a lesser extent than in glands heat shocked in absence of BM. The 93D puff, which is highly induced by either of the treatments alone, is relatively less active in glands exposed to TS and BM simultaneously. When a 10 min BM treatment (at 24 degrees C) incorporation on all TS puffs is relatively less and significantly, in both cases, the 87C puff is much less active active (more so in TS followed by BM treated glands) than the 87A puff. Also, in both these treatments, the 93D puff does not show ant additive effect on the BM and TS treatments. These observations are discussed in the light of possible role of the 93D puff in modulating the heat shock response.

Consumption and utilization of a soyflour-wheat germ diet by larvae of the tobacco budworm parasitized by the tachinidEucelatoria sp

The number ( $$\bar X$$ =2.4) ofEucelatoria sp. maggots that completed development in 4th- or 5th-instar larvae of the tobacco budworm (TBW),Heliothis virescens (F.), was significantly greater (P<0.05) than the number ( $$\bar X$$ =1.2) that completed development in 3rd-instar larvae. Maggot development time decreased with increasing number of maggots per host larva. It also decreased with advancing larval instars. The range was 6.9±1.1 days in early 3rd-instar TBW larvae and 5.0±0.8 days in early 5th-instar TBW larvae. Unparasitized 3rd- or 4th-instar TBW larvae consumed significantly more food than did similar aged larvae parasitized byEucelatoria sp., but larvae parasitized during the early 5th-instar consumed more food than did similar aged unparasitized larvae. Consumption by 4th- or 5th-instar larvae increased significantly as maggot densities increased from 1 to 3 per host larva, but decreased at a density of 4 or more maggots per host larva. Although body weight gain and consumption were both significantly reduced 48 and 120 h after parasitization of late 3rd-instar larvae (6 days old), the approximate digestibility (AD) value was significantly greater for parasitized than for unparasitized larvae. Unparasitized larvae were more efficient in converting digested food to body substance (ECD) than parasitized larvae, but the efficiency in conversion of ingested food to body substance (ECI) was similar for both parasitized and unparasitized larvae.