Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-23T08:01:18.276Z Has data issue: false hasContentIssue false

Heterosis in Single, Three-way and Double Cross Hybrids of Silkworm, Bombyx mori L.

Published online by Cambridge University Press:  19 September 2011

Sripada M. Udupa
Affiliation:
Department of Sericulture, University of Agricultural Sciences, GKVK, Bangalore-560065 (India)
B. L. Visweswara Gowda
Affiliation:
Department of Sericulture, University of Agricultural Sciences, GKVK, Bangalore-560065 (India)
Get access

Abstract

An investigation was carried out in India, to study the extent of heterosis expressed in single, three-way and double cross hybrids with respect to important economic characters. The results were discussed in terms of relative heterosis (heterosis over mid-parent value) and standard heterosis (heterosis over standard check variety). Significant negative relative heterosis was observed for total larval duration in single and majority of the three-way crosses; whereas it was positive and significant in double cross hybrids. The commercial characters like cocoon and pupal weight, shell percentage, filament length and denier, recorded positive relative heterosis in most of the single and three-way crosses; whereas they were negative and significant in most of the double crosses. In general, higher degree of heterosis was expressed in single crosses followed by three-way and double crosses for the characters studied.

Résumé

Une enquête pour etudier l'importance du degré d'hybridité exprimée chez les hybrides par rapport aux caracteristiques economiques importants chez le ver à soie a étè effectuée en Inde. Les resultats obtenus ont étè analysé en terme d'hybridité relative (hybridité sur la valeur parentale moyenne) et standart (Hybridité sur la verification des varietes). Une hybridité relative d'une valeur negative significative fut observée pendant la durée du developpement larvaire chez le croisement simple et triple contre une hybridité positive et significative chez les souches hybrides resultant d'un croisement double. Les caracteristiques commerciaux par exemple; le poids du cocon, le poids des chrysalides, le pourcentage de la coquille, la longeur et le denier du filament ont enregistré une humidité relative positive chez la majorité des souches hybrides émanant d'un croisement simple et triple contre une valeur significative et negative chez la majorité des hybrides resultant d'un double croisement. En genèral, un degré elèvé d'hybridité a étè exprimé chez le croisement simple suivit du croisement triple et double pour les caracteristiques etudies.

Type
Research Article
Copyright
Copyright © ICIPE 1988

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Anonymous (1976) Dialogue with Dr. Tazima. Indian silk 15, 79.Google Scholar
Anonymous (1985) Silkworm Breeding and Genetics Section. Annual Report, Central Sericultural Research and Training Institute, Mysore, India, pp. 120.Google Scholar
Chaudhary, B. S., Paroda, R. S. and Singh, V. P. (1978) Stability and genetic architecture of harvest index in wheat (Triticum aestivum L.) Z. pfl. 81, 312318.Google Scholar
Datta, R. K. (1984) Improvement of silkworm races (Bombyx mori L.) in India. Sericologia 24, 393415.Google Scholar
Harada, C. (1952a) On the double cross of the silkworms. Japan. J. Breed. 2, 3.Google Scholar
Harada, C. (1952b) On the three-way cross of the silkworms. Japan J. Breed. 3, 99.Google Scholar
Krishnaswami, S., Narasimhanna, M. N., Suryanarayana, S. K. and Kamaraj, S. (1973) Silkworm rearing. Manual on Sericulture, Vol. 2. FAO of UN, Rome, p. 131.Google Scholar
Pannegpet, P., (1973). Survey on the practical characters of three-way cross and double cross hybrids of bivoltine silkworm races. Bull. Thai Sericultural Research And Training Centre, Thailand 3, 8182.Google Scholar
Pannegpet, P. and Jaroonchai, J. (1975) Survey on practical characters of double cross hybrids of bivoltine silkworm races (2). Bull. Thai Sericultural Research And Training Centre, Thailand 5, 8586.Google Scholar
Rai, B. (1979) Heterosis Breeding. Agrobiological Publications, Delhi, p. 183.Google Scholar
Yokoyama, T. (1974) Utilization of heterosis in Japanese Sericulture (SABRAO Proa). Indian J. Genet. 34A, 206210.Google Scholar