Agro Inform reproductive and viability characteristics of

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Agro Inform
high-tech features are collected in a single genotype. Given the above, newly created breeds and hybrids 
can be recommended in genetic, breeding research.
Conclusion 
Within the framework of the improvement of the C-8 ngl breed balanced on embryonic lethal genes, 
theoretically expected results have been achieved practically in every generation.
From the obtained results of the study, it can be concluded as follows:
1. Imbalance of the double lethal in the unique C-8 ngl breed, embryonic viability was not significantly 
reduced as a result of this or that lethal acquisition. However, in the next stages of improvement work, it is advisable 
to increase the intensity of selection-breeding work and strictly control the lethal balance.
2. The high indicators of viability and satisfactory cocoon productivity of this new system, which is taken as 
an analog for the C-8 ngl breed, allow it to be recommended to silkworm egg processing enterprises.
3. Based on the weight and physiological defect indicators of the eggs of the egg-laying, along with the L-28 
line taken as an improver the combination ♀ (tr24w
2
w
2
× L-67) × ♂ (L-28 × C-8 ngl) created as a result of analytical 
crossbreeding was proved to be acceptable as a second improver for future generations.
4. The results obtained show that no adverse effects of embryonic Z-lethal genes on the reproductive traits 
of the mulberry silkworm were observed.
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