Genetic Divergence, Implication of Diversity, and Conservation of Silkworm, Bombyx mori

Table 2

Genetic divergence study reported in silkworm using enzymes, protein, and isozymes.

SL number	Reference number	Number of genotypes and clusters	Measures of genetic diversity	Conclusion
1	[32]	—	Esterase used for polymorphism	Polymorphism noticed among genotypes.
2	[125]	—	Protein profiles used for genetic diversity	Divergence arises internally after a relatively long amino terminal sequence which appears to be conserved. A plausible explanation for the observed genetic variability is the occurrence of relatively large unequal crossing-over exchanges in the repetitive domain of the fibroin gene.
3	[126]	—	Esterase used for polymorphism	Polymorphism noticed among genotypes.
4	[127]		Acid phosphatase used for polymorphism	Polymorphism observed among genotypes.
5	[128]	20	Enzymes	Rich genetic diversity among genotypes.
6	[129]	10	Esterase used for polymorphism	Polymorphism noticed among genotypes.
7	[36]	12 and 6	Nei and Li (1978) [130] and; Yeh et al. (1999) [131]	Rich genetic diversity among genotypes.
8	[132]	8 and 2	Enzymes and UPGMA	Genetic diversity noticed among genotypes.
9	[133]		Nei and Li (1978)	The protein profile of different breeds has indicated the polymorphism and genetic diversity among silkworm breeds.
10	[37]	15	—	Esterase exhibited polymorphism among the bivoltine breeds.
11	[134]	6 and 3	Protein	Genetic differentiation among populations of different races.
12	[44]	12 and 2	Nei and Li (1978) UPGMA	The mean value of FST (0.2224) calculated on the base of the established polymorphism showed that 22.24% of the genetic variability was observed between the different strains, which corresponds to the level of the interstrain genetic differentiation.
13	[40]	21 and 8	Nei and Li (1978) UPGMA	Genetic variations were observed and they can be identified by relating with their morphology and geographical origins
14	[135]		Nei and Li (1978) UPGMA	Protein profiles studied and presence of rich genetic diversity among germplasm stocks. Different origin accessions established a close relationship indicating close affinity in protein pattern.
15	[41]	15	Esterase used for polymorphism	Variation in esterase pattern was observed among genotypes.
16	[43]	10 and 2	Nei (1978) by UPGMA dendrogram (Sneath and Sokal, 1973)	A perusal of genetic diversity within and among strains indicated that 34.72% of the observed variation occurred among strains and the rest of the variation (65.28%) within strains. Their rich genetic diversity needs to be exploited in conservation and breeding programme.
17	[136]	4	(Swofford and Selander, 1981)	The lower degree of observed heterozygosity and the higher degree of homozygotes proved the inbreeding effect.
18	[42]	15 and 3	Nei (1978) and UPGMA	Japanese and Chinese strains could not be totally separated by the isoenzyme system analysis. The results indicate that, in spite of the genetic distance and differentiation among the lineages, they cannot be separate just with the isozymes alleles. The high FST value (0.6128) allows the conclusion that the lineages are differentiated.