Technological Results Obtained Using Domestic Silkworm Genotypes in Various Seasons
Lala Abdullayeva1 , Arzu Mirzayeva2* , Gulabatin Humbatova1 ,
Arzu Mammadov3 , Seyfali Kahramanov4
Abstract. Since one of the primary objectives of sericulture is the production of high yields of high-quality raw silk output, any domestic silkworm line (Bombyx mori) demonstrating enhanced silk productivity is considered of significant value. Just as biological indicators reflect overall agricultural performance, technological indicators must correspond to the requirements of industrial processing. It is well established that certain biological and technological traits in silkworms are interrelated, and improvement in one group of traits often leads to corresponding enhancement in the other. For example, an increase in the cocoon shell ratio (silk content of fresh cocoons) is associated with a higher conversion efficiency from fresh to dry cocoon weight. This, in turn, results in an increased cocoon shell ratio of dry cocoons and a higher raw silk yield. In this context, the technological characteristics of the silkworm lines were evaluated. The results presented here are based on a three-year experimental study conducted under suboptimal rearing conditions across three seasonal cycles (spring, summer, and autumn). Raw silk yield from cocoons—considered the principal technological indicator of productivity—was 44.2% for the Atlas 1 line and 44.3% for the Atlas 2 line. Cocoon reelability rate (moth emergence) was relatively high in both lines, reaching 88.8% in Atlas 1 and 90.3% in Atlas 2. The filament length reeled from a single cocoon averaged 1,693 m in Atlas 1 and 1,309 m in Atlas 2. Atlas 1 line is characterized by a longer and finer filament, whereas Atlas 2 produces a thicker filament. This difference suggests that Atlas 2 may provide silk with higher mechanical strength and higher quality, while Atlas 1 yields finer and longer fibers. The metric number—an indicator of filament fineness and length—was 4,422 m/g for Atlas 1 and 3,700 m/g for Atlas 2, with higher values corresponding to finer and longer filaments. Overall, the Atlas 1 line is distinguished by a fine, long filament, a satisfactory reelability rate, and high raw silk yield. In contrast, the Atlas 2 line exhibits a thicker filament of moderate length, a high reelability rate, and similarly high silk productivity. The results of the selection experiment further indicate that maintaining both genotypes under suboptimal feeding conditions is effective. Such selective pressure enhances technological traits while improving environmental adaptability and resilience.
Keywords: selection, line, domestic silkworm, cocoon, silk, technological indicators