Evaluation of genetic potential of the polyvoltine silkworm (Bombyx mori L.) germplasm and identification of parents for breeding programme

Abstract

In the present study, polyvoltine germplasm stock of Andhra Pradesh State Sericulture Research and Development, Institute (APSSRDI) was evaluated for its performance based on quantitative and qualitative traits. Twenty-one oval and 10 peanut cocoon shaped lines were reared in different seasons of the year. Since the polyvoltines are non-diapausing, six generations were reared and evaluated for various economically important traits based on evaluation index and sub-ordinate function statistical methods. Ten top ranked lines obtained by using both the methods were identified as potential parental strains. Among oval lines, APM14, APM11, APM18, APMW9, and APM19, and among peanut lines APMD5, APMD1, APMD3, APMD9 and APMD8 were selected as base material. The identified high yielding lines will be used in various breeding programmes as initial parents for the synthesis of superior polyvoltine breeds/hybrids.

Evaluation of economically important traits from sixteen parental strains of the silkworm Bombyx mori L (Lepidoptera: Bombycidae)

“…All of the studied strains in here are polivoltine, are generally more resistant to climatic changes and produce considerably less silk than the mono-or bivoltine strains (Rao et al 2006). However, our data indicated that the strains from the ACESP/UEM germplasm bank are also great producers with higher RSP values, which are close to the values reported for bivoltine strains (Goel et al 2007).…”

“…However, Strains C121-A and C122-B generated lower values for SGW (Table 2), but exhibited the greatest values of RSP, indicating the silk gland development may be uneven among different strains, especially when 5 th instars were sampled earlier in their development. The CW (1.5 g), SW (0.4 g) and RSP (18.3%) mean values obtained for all 16 strains were higher than in some of the studies available in the literature (Porto & Okamoto 2003, Porto et al 2004, Rao et al 2006.…”

Biological and molecular characterization of silkworm strains from the Brazilian germplasm bank of Bombyx mori

“…In a study performed by Rao et al (2006) using silkworm strains from a polyvoltine germplasm bank, a mean value of 461 eggs per laying was found, which is closer to the value observed in our study. Nevertheless, pupation rates of the multi-and polyvoltine strains reached a value greater than 86%, which is higher than that observed in our study (80%).…”

“…However, a lower value (14.99%) than that observed in this study was reported by Kumaresan (2007). Other strains from a Pakistani germplasm bank (Hussain et al, 2010) and a polyvoltine germplasm bank (Rao et al, 2006) Table 2. Qualitative traits related to 14 Bombyx mori strains from the UEM Brazilian Germplasm Bank.…”

Genetic Diversity Studies in Six Bivoltine Races of Bombyx Mori L., Based on Phenotypic Characters.

“…silkworm breeds play a vital role in the success of sericulture industry. Thus the breed development and improvement is a continuous process which aims at providing suitable genotypes with desired traits (Datta, 1984;Rao et al, 2006). Enrichment of silkworm breeds / hybrids have always been one of the important factors contributing to increase the productivity in sericulture sector.…”