• Journal of Environmental Science International
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• v.32 no.9
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• pp.671-674
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• 2023

This study was conducted to evaluate the effects of using Hermetia illucens larvae as environmental purification insects on ammonia and Hanwoo manure for 15 days in the Hanwoo farms. H.illucens larvae were allocated into four treatment groups and three replicates using a randomized block design. The treatments were as follows: control, normal 1000 g of Hanwoo manure, T1, 1000 g of Hanwoo manure + 100 g of 2nd instar H.illucens L. larvae, T2, 1000 g of Hanwoo manure + 100 g of 3rd instar H.illucens L. larvae, and T3, 1000 g of Hanwoo manure + 100 g of 4th instar H.illucens L. larvae. After 0 days, ammonia fluxes did not occur in the 2nd, 3rd, and 4th instar H.illucens larvae treatments (p<0.05). Among the characteristics of Hanwoo manure, the pH and nitrogen content increased for each larvae instar of H.illucens, whereas ADF and NDF content decreased (p<0.05). In particular, nitrogen contents were found to be highest in the 3rd instar larvae of H.illucens owing to their greater ability to decompose Hanwoo manure than larvae at other growth stages.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.480-485
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• 1992

Laboratory studies were done to evaluate the effects of diflubenzuron on embryonic and postembryonic development of Riptortus clavatus Thunberg. Diflubenzuron prevented egg hatch; younger eggs(O-12 h old) were 2 times as susceptible as older(48-60 h old) eggs, but embryos of both younger and older eggs developed normally. Susceptibility of nymphs to diflubenzuron decreased with each successive molt. Compared with the first instar, relative tolerance to diflubenzuron was 1.5 times for the second instar, 18.2 times for the third instar, 39. 4 times for the fourth ins tar and 42.4 times for the fifth instar. Even as low concentrations, diflubenzuron prevented significant numbers of third instar nymphs from developing to fourth and fifth instar nymphs or adults. Weight, longevity and fecundity of adults surviving treatment in the final (fifth) instar were also adversely affected.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.2
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• pp.171-174
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• 2002

Two systemic fungicides, SF1 (Bavistin, a carbandazim fungicide 50% WP, Rallis India ltd., India) and SF2 (Bayleton 25% WP-Triadiamefon, a Triazole compound, Rallis India Ltd., India) were screened for control of muscardine disease in silkworm, Bombyx mori. One and two percent of SF1 and 0.05 and 0.1 % of SF2 in aqueous solution were found to be effective in in vivo condition for the control of the disease. These fungicides, on feeding through mulberry leaves continuously for two days to 4$^{th}$ and 5$^{th}$ instar silkworm larvae inoculated topically with conidia of Beauveria bassiana (4$\times$10$^{6}$ conidia/ml) resulted in reduction in mortality due to muscardine by over 90% as against 100% mortality in inoculated control. SF1 at 1% reduced the mortality by 90% in 4$^{th}$ instar and 91% in final instar silkworm while at 2%, the reduction was 92% and 96%, respectively. SF2 at 0.05 and 0.1 % concentration reduced the mortality by 82 and 88% during 4$^{th}$ instar and by 88 and 92% during 5$^{th}$ instar, respectively.

• Applied Microscopy
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• v.20 no.2
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• pp.12-22
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• 1990

The morphological characteristics and changes of the foregut in the grasshopper (Oxya sinuosa Mistshenko) have been studied with the special reference to the developmental stage. In light microscope level, the epithelia are seen the cuboidal shape in the 5th instar nymph and the adult. A number of pigment granules are appeared in the cuboidal epithelium of the 5th instar nymph, however the pigment granules were a few in the adult. Indistinct or undifferentiated folds of the epithelial layer were appeared in the 5th instar nymph, whereas the well-developed folds were in the adult. The well-developed muscular layers are seen in the 5th instar nymph, however in the adult the muscular layers are appeared thin or a few layer except the crop. In electron microscope level, in the foregut epithelium, a few round or oval shaped mitochondria, well-developed rER, Golgi complex, lysosome and a number of vacuoles were appeared in the cytoplasm. Two types of pigment granules, electron dense or homogenous and low electron dense or lamellar profiles, are seen in the esophageal epithelium. The crystalline profiles and plasma membrane infoldings were also appeared. In the foregut epithelium of the 5th instar nymph, however the cell organelles were generally undifferentiated and in the crop two types of pigment granules as the adult esophageal epithelium were also found.

• Journal of Sericultural and Entomological Science
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• v.29 no.2
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• pp.38-43
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• 1987

The just molted larvae of the fifth instar were fed on with cadmium trated mulberry leaf and on the third day of the fifth instar the daily change of the total protein, activities of GOT and GPT in larvae haemoymph were sexually analyzed. The result obtained are summarized as follows : 1. The total haemolymph was decreased by cadmium treatment. A decreasing ratio of the total haemolymph protein was higher at the later development stage of the male fifth instar than the female fifth instar. 2. There seemed a slight difference in albumin content of the female blood along with the fifth larvae development between control and cadmium treatment where 7% decrease of blood albumin took place with cadmium treatment comparing to that of cotrol. Contrarily a decrease of blood globulin was made on both sexes. 3. The activities of GOT and GPT were inhibited by cadmium treatment.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.150-157
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• 1998

This study was carried out to define the effects of anti-juvenile hormone analogue(AJH) treatment at different silkworm larval stages on some silk filament properties. It was revealed that the treatments at the 1st and 2nd days of the 3rd instar as well as the 1st day of the 4th instar resulted to trimolters induction without lethal effect. The trimolters induced by treatment at the 1st day of the 4th instar showed the shortest larval duration and the lowest single cocoon weight, cocoon shell ratio, cocoon size, single filament length and denier of filament compared with those of the control, while the trimolters induced by the 3rd-instar treatment showed intermediate values. All treatments showed no significant differences from the aspect fo degumming ratio, elongation rate and crystallinity index of fibroin. However the silk filament obtained from the treatment at the 1st day of the 4th instar showed the highest tenacity which was revealed to be related to the better uniformity of filament by the means of microscopic photographing. FT-IR spectroscopy of the silk fibroin showed a sharp and strong peak at the position of 794.72 cm-1 in all AJH-treated samples regardless of trimolters induction, which was absent in control.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.139-143
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• 2001

The efficacies of several entomopathogenic nematodes of Steinernema and Heterorhabditis spp. were examined against tobacco cutworm, Spodoptera litura Fabricius. H. bacteriophora HY showed 100% mortality after 20 h against 2nd instar of tobacco cutworm. In the case of 3-4th instar, S. carpocapsae PC, H. bacteriophora HY and S. monticola CR showed 100% mortality after 47 h. In the case of 5-6th instar, S. carpocapsae PC proved more effective than the others. Generally, the number of nematodes harvested as their size decreased. Also, the highest number of nematodes was obtained in the 5-6th instar of S. litura by H. bacteriophora HY, showing about $1.3{\times}10^6$ nematodes per larva. In vitro cultured S. carpocapsae PC showed 100% mortality after 73 h against 5-6th instar tobacco cutworm, indicating that nematodes produced in vitro can be potentially used for the biological control of S. litura instead of nematodes in vivo.

• Applied Microscopy
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• v.20 no.1
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• pp.105-119
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• 1990

In order to know the morphological characteristics and changes according to the developmental stage, the comparative observations have been studied by light and electron microscope on the midgut(gastric caecum, stomach) of the grasshopper(Oxya sinuosa Mistshenko). The results obtained are summarized as follow : In light microscopic level, the cuboidal shaped cells of the gastric caecum in the 5th instar nymph are differentiated the columnar epithelium in the adult. A number of pigment granules are appeared in the gastric caecum of the 5th instar nymph, however the pigment granules were absent in the adult. Indistinct or undifferentiated folds of the epithelial layer were appeared in the 5th instar nymph, whereas the well-developed folds were appeared the gastric caecum in the adult. The well-developed muscular layers are seen in the 5th instar numph, however in the adult the muscular layers are appeared thin or a few layers. In electron microscopic level, in the midgut epithelium, a number of well-developed rER, a few lipid droplets, multi vesicular bodies, small vesicles and glycogen granules were found. Two types of the pigment granules in the gastric caecum of the 5th instar nymph were appeared, whereas the whorl-membrane, a few secretory granules and one type of the gastro-entero-endocrine cell were found in the adult midgut. The light and dark cells could be distinguished in the stomach epithelim of the 5th instar nymph.

• Journal of Sericultural and Entomological Science
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• v.9
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• pp.35-38
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• 1969

This study was carried ont to investigate the effect of feeding amount on the metric characters of silkworm at each day of 5 th instar. The results obtained from the study are summarized as follows: 1. The increased amount of feeding did not affect on the metric characters except the character, number of cocoon per litre, by each day of 5 th instar. 2. The decreased amount of feeding did affect the weight of cocoon, weight of cocoon layer and did not affect the pupation, best cocoon rate, cocoon layer rate and number of cocoon per litre by each day of 5 th instar. Namely, the weight of cocoon or weight of cocoon layer was decreased by 12 to 17 per cent in decreasing amount of feeding through 5 th instar. Weight of cocoon or cocoon layer decreased by 5 per cent in the decreasing amount of feeding at just 7 th day of 5 th instar.

• Korean journal of applied entomology
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• v.29 no.1
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• pp.1-5
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• 1990

A morphological study on the immature and adult stages of Anagrus incarnatus Haliday was carried out under laboratory condition at 25$\pm$1$^{\circ}C$. The egg is sausage-shaped with a long slender pedicel. The first instar is a bag-shaped larva. The second instar larval form of A. incarnatus is similar to he "histriobdellid" stage. The antenna has 9 and 13 segments of the female and male, respectively. The first funicular segment of the female's antenna is very short, subspherical or globular type and the third funicular segment with one sensory ridge is longer than the forth. The forewing of A. incarnatus has 8-9 rows of discal hairs providing no bare space at the broadest part. The length of ovarian eggs, egg, 1st instar, and 2nd instar of A. incarnatus is 0.165, 0.215, 0.290, and 0.535 mm, respectively, and the width of each stages is 0.025, 0.057, 0.082, and 0.110 mm, respectively. The developmental periods for egg, 1st instar, 2nd instar, prepupa, and pupal stage are about 1, 1, 4, 1, 5-6 days, respectively.pectively.