High levels of endogenous polyamines indicate superiority of Morus alba L. varieties for improved silk production in Bombyx mori L.

Abstract

Mulberry (Morus alba L.) is an essential plant for sericulture. The composition of mulberry leaf determines the growth of Bombyx mori L. Polyamines (PA) were shown to be vital for growth, development, and stress tolerance in various plants. However, their presence and role in mulberry have not been studied yet. Experiments to examine the polyamines (PA) in four distinct cultivars of M. alba leaves by quantitative and qualitative analysis, revealed that PAs were found to be present in all four mulberry cultivars, and the cultivar V1 showed significantly higher PA levels when compared to the others. Thin-layer chromatography revealed several PA bands with different strengths among leaf varieties. The common polyamines found in all four cultivars were putrescine, spermidine, and spermine. The antioxidant potential of the V1 mulberry cultivar was significantly higher when compared to the others. V1 fed larvae of B. mori showed significant enhancement in the larval weight, cocoon weight, and length of the filament reeled. This study illustrates that higher endogenous PA levels of the V1 mulberry cultivar led to higher production of silk.