• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.203-208
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• 2003

Rearing temperature influences food consumption, conversion and cocoon production in silkworm Bombyx mori L. Young age $({1^st}to{3^rd} instar)$ worms of Pure Mysore, a multivoltine were reared at 26, 28, 30 and $32^{\circ}C$ followed by combinations of these temperature levels during late age $({4^th} and {5^th} instar)$. Food consumption, conversion, larval duration and growth for each instar were recorded. The influence of combinations of these temperature levels during rearing on survival and cocoon production was assessed. Food consumption increased with the temperature up to $4^th$ instar and decreased during $5^th$ instar. Temperature beyond $28^{\circ}C$ during young age followed by higher temperature ($30^{\circ}C$ and above) has shown deleterious effect on cocoon production. The paper discusses the rearing performance in relation to food intake and conversion under the tested temperature levels.

• Journal of the Korea Organic Resources Recycling Association
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• v.20 no.2
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• pp.89-95
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• 2012

This study was carried out to investigate the effects of endocrine interupter, Nonylphenol and DEHP on the cocoon production, the hatchability of cocoon and the number of offsprings per cocoon of Eisenia fetida. And the cocentrations of Nonylphenol and DEHP of sewage sludges in Pocheon city (Northeastern area of South Korea) were also investigated. Nonylphenol below the concentration of 100 mg $kg^{-1}$ did not reduce the cocoon production, the hatchability of cocoon and the number of offsprings per cocoon. DEHP above the concentration of 1,500 mg $kg^{-1}$ reduced the cocoon production, and DEHP over the concentration of 2,500 mg $kg^{-1}$ could reduce the hatchability. There was no Nonylphenol in sewage sludge of Pocheon city, but maximum concentration of DEHP was 1,640mg $kg^{-1}$, which could make the population of Eisenia fetida extinct gradually if sewage sludge of Pocheon was supplied to Eisenia fetida for a long time.

• Journal of Sericultural and Entomological Science
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• v.32 no.1
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• pp.31-37
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• 1990

For fine-denier cocoon filament production, the precocious trimolting silkworms were induced by the treatments with both the imidazole compound "KK-42" hating anti-juvenile hormone activity and high temperature, and their growth, dietary efficiency, cocoon and cocoon filament qualities were compared with those of normal tetramolters as control. 1. The percentage of precocious trimolters was higher in the application of KK-42 than the treatment of high temperature. The effective concentration of KK-42 was 10$\mu\textrm{g}$/1arva. The high temperature treatment for 48 hour was more effective than 36 hour treatment, and silkworm larvae fed on mulberry leaves were more sensitive than artificial diet to induce trimolters. 2. The larval duration of the trimolters induced by KK-42 was 5.17 day shorter than that of normal tetramolters in mulberry leaves rearing, and the increasing pattern of body weight in the 4th inster larvae of trimotlers was similar to the 5th instar larvae of normal tetramolters. 3. The qualities such as cocoon weight, cocoon layer weight and cocoon layer ratio of precocious trimolter induced by KK-42 were much lower those of normal tetramolters: the cocoon weight and cocoon layer ratio were 0.78g, 14.2cg and 18.4% in mulberry leaves rearing, and 0.86 cg, 10.3cg and 12.3% in artificial diet rearing, respectively. 4. The size of cocoon and cocoon filament was smaller in the precocious trimolter, both KK-42 and high temperature, as compared with that of the normal tetramolters. 5. The efficiency of cocoon layer production of the precocious trimolters by the KK-42 was lower than that of the normal tetramolters: amount of the cocoon layer production per 1g of dry mulberry leaves ingested was 7.97cg in the precocious trimotors, while 9.20cg in the normal tetramolters.

• International Journal of Industrial Entomology and Biomaterials
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• v.1 no.2
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• pp.87-90
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• 2000

This paper has reviewed the China Sericulture history in the 20th century. On the basis of the current sericulture production, sericulture area distribution, problems and challenges, it has been forecasted that China sericulture will be developed as following points: 1) On a stable basis, cocoon production increased gradually to a suitable amount; 2) Quality cocoon production bases established to form a regionalized, industrialized and specialized sericulture structure; 3) With increase of householding rearing capacities, rearing facilities improved; 4) Production efficiency raised and silk product quality improved through technical innovation; 5) New and diversified products developed from Sericultural resources with new and high technologies.

• Journal of Sericultural and Entomological Science
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• v.25 no.1
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• pp.34-43
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• 1983

These studies have been carried out to find better locations for sericultural service regardless of the international silk market fluctuation in Korea. In order to acieve the purpose, various investigations and analyses have been carried out for more than four hundred sericultural communities to find out the main factors which caused to decrease in cocoon production in spite of a gloomy past silk market. Now, we believe that we have set up some fundamental guide lines in developing sound serviceable sericultural communities in Korea in case the government accepts the written advices, and the results obtained are as follows: 1. The Korean sericulture has been very prosperous from the 60's to the 70's. In 1976 the cocoon production was at its peak, reaching 41,704M/T from which its decline took place with annual averages of 18.5% for total cocoon production and 16.4% for mulberry field. These figures represent a quantitative decrease to one-third of the total amount in 1976. Since then, the Korean sericulture had continuously suffered from a shortage of raw silk resulting in a slow development of sericulture. At present, a steady development through all possible measures is great importance. 2. The downfall of the korean sericulture resulted from two factors of such as the external, which led to the decline in the price of raw silk at the international market and restrain of import and, the internal, resulting in the little increase of cocoon price and a comparatively lower benefits from the sericulture than from other cash crops. 3. The already established sericultural zone collapsed and then reorganized with the outstanding regional specialization so the decline in total cocoon production in the country. Based on the agricultural regions, 1980 cocoon production was very stable in the mountaineaus area of the east-south which used with intercropping. In this area there was small decline of 33% compare with that of the 1979, and with 70% decline in the dry field farming area of Kangwon Do. In an administrative districtwise, six counties beginning with Sanchnung county of Kyungsang Nam Do, showed less than 20% decline of cocoon production, sixteen counties beginning with Samchuck county of Kangwon Do marked above 80% decrease of cocoon production. In the smaller unit area-wise, there was a big difference among them. twenty-five myons rather increased and a hundrd fourty-three myons decreased above 80% of it. 4. The cocoon production was positively correlated with the decreasing percentage of cocoon production per household. It was also affected by the ratio of the mulberry field area to the total cultivated area per household and cocoon productivity per 10a. 5. Four hundred sixty-four villages in the seventeen counties were surveyed on the basis of farm management and techniques concerned ('80/'79), and then the results were evaluated by using of computer. These results are summarized as foolows: (1) Cocoon production per household There was no difference among the agricultural regions in cocoon production. The cocoon production per household in the comparatively stable villages increased from 100.8kg in 1979 to 122kg in 1981. Cocoon yield in the stable villages decreased by 20% of '81/'79. The cocoon production per house hold in while that of the unstable villages decreased by more than 40% from 102.9kg in 1979 to 82kg in 1981. (2) Cocoon yield per 10a mulberry field The cocoon yield per 10a was higher in the plain area than in the mountaineous area. The stable villages had an average of 73.4kg cocoon yield/10a while the unstabe ones had only an average of 55kg. (3) Adoption the mulberry branch rearing method The branch rearing method was more popular in the plain area than in the mountainous area. In the stable vilages adopted 24.2% in spring and 16.7% in autumn of 1979. In 1981 it shwed increases of 34.3% and 10.1% in the two seasons respectivly. However, the unstable villages showed 13.3% and 126% in both seasons, respectively. (4) The patterns of the combined management system in the sericultural farming The popular management system in the sericultural from was combined with rice and other cash crops, showing 55% of the total households surveyed. Fourteen percent of the households combined the management system with rice and other cash crops and 14% of the households combined with rice only. The villages wich earned less than 20% of the total income from the sericulture reached 81% of the total houscholds indicating that they were still far beyond a complete combination system. (5) Damage by agricultural chemicals The damage caused by agricultural chemicals was mainly due to the protection of rice against insectpests and diseases in the plain areas and took place mostly in the autumn season. The chemicals applied was 65% of Iiquid and 35% of powder forms and 35% of damage was from granulat form of the chemicals. The use of the granular chemicals was low because of high cost.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.135-139
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• 2001

Experiments were held in Egypt to test a new Package of practices for commercial cocoon production, including adding secondary macro and micronutrients to the mulberry garden, disease free rearing regime, low temperature rearing in young instars and natural mounting fur silkworms. This package for seed silkworm rearing lead to increase in fecundity by 67-121eggs (15.12-26.22%) and yield of standard boxes per 1 parent egg boxes by 57-58 egg boxes(48.33-51.66%) respectively in comparison th the traditional cocoon production technology.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.99-105
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• 1969

The results of investigation and management analysis for the silk filatures in Korea until 1968 are evaluated as followings. (1) The average cocoon purchasing amount for a filature was found as 10,800kg and they are processed 105kg per man on the cocoon assorting process, 8,683kg per day during the drying process of which 42 percent are dried with low temperature drying system. (2) The average cocoon cooking capacity is 50 g, cocoon per minute, but the cooking capacity per man is smaller in case of larger factory. (3) The silk production capacity per month per a filature is 6,000kg and the amount gets smaller in case of larger factory. (4) The employee cost per one kg of raw silk production was found as high in smaller factory and it was found that 200~300 sets size was the optimum capacity for operation. (5) In case of multiends silk reeling machine, the employee cost for the silk reeling process acts as the most peculier factor among six different cocoon processes and it is reached to conclued to deduct the number of employees for this process in order to deduct the production cost. (6) The correlation coefficients between cost factors and total labour cost was found as 46 percent, therefore the rest (54％) will be the production cost other than labour cost.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.47-50
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• 1970

There are many factors affecting the development of sericultural industry in Korea. The setting of a rational pricing system for sericultural products is one of important activities of the Korean Government to improve the incentives to producers. The determination o： the prices for many years were based on the production costs including a certain level of profits. Some of cost items are in conflict both in cocoon producers and silk-reeling industries. Government officials have to evaluate these conflicting problems and estimate the consequences of their decisions. In this situation the final decision often became political decisions. This analysis is aimed at providing an alternative method of setting the prices of sericultural products. The criteria of the equilibrium employed in this analysis are based on economic principle which equilibrium condition is determined by the relationships between the marginal productivity of input factors and factor prices. In order to obtain the related information Cobb-Douglas'functions were fitted using KIST computer and data were obtained mostly from the Bank of Korea and the Ministry of Agriculture and Forestru, An important assumption is that "Opportunity Costs" of factors input in both cocoon production and silk-Peeling industries are same, The major finding s obtained are as followings. 1) The sum of coefficient of production elastisity in silk-reeling industries is greater than one. Silk-reeling industries are operating under the situation of increasing return to scale and it is, therefore, expected to develop the industries as the capital-intensive large scale. 2) The cocoon producing farmers are under the situations of the decreasing return to scale and it is expected to continue their cocoon farming as the labor-intensive small scale, assuming the present level of production technology. As the development of commercial farming, the resources input in cocoon production will be shifted to the production for higher profitable crops, 3) The price elastisity of production is higher in cocoon production than in silk-reeling industries. It is expected that the price changing effects on domestic production will be resulted from cocoon producers. 4) Based on analysis results of marginal productivities and the opportunity costs of resources, cocoon price for meeting equilibrium price condition is to be increased by 8-16 percent or standard price level of silk increased by 6-8 percent. There were the possibilities of over evaluation on opportunity cost of resources input in silk-reeling industries, or income transfered from the farmers to the industries. It is recommended that the prices for meeting equilibrium price conditions are to be determined by 72 percent for cocoon and 28 percent for silk-reeling costs, based on standard level of the exporting prices.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.147-151
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• 2012

Fifteen races resulted from silkworm breeding program at Sericulture Research Department (SRD) were used for hybridization. Fourteen hybrids were obtained and coded as; Giza C, D, R, S, T, U, A, V, W, P, H, L and Qanater 1, 2. The traits of cocoon weight, cocoon shell weight, pupal weight, cocoon shell ratio, silk productivity, fifth instar duration, total larval duration, number of cocoon per liter and pupation ratio were evaluated. Data were analyzed by using three formulae of heterosis over better, mid and check parent values. Hybrids of Giza V, C, N, Qanater 1 and 2 are promising and could be used in commercial cocoon production. Generally, there are some new hybrids can be exploited in commercial scale. Also, the local races can be evolved using the hybridization, inbreeding and selection program.

• Journal of Sericultural and Entomological Science
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• v.13 no.2
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• pp.151-154
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• 1971

In the silkworm egg production, cutting of the cocoon's edge formed by silkworms forced to aid the emergence, and emergence is related to the amount of alkaloid liquid in the sucking stomach in certain varieties. In this study, there was no difference between cutting of portion and sex, and no significant between cutting of both sides and one side cocoons when comparing their emergence ratio. Expenditures and emergence ratio between both sides and one side cutting off must be studied in coming future.