The Effect of Feeding with Central European Local Mulberry Genotypes on the Development and Health Status of Silkworms and Quality Parameters of Raw Silk

Abstract

Silkworm rearing activities ceased in the 1970′s in several European countries. Attempts on the re-establishment of ecological and sustainable sericulture in Slovenia and Hungary are ongoing. The aim of the study was to assess the usability of locally adapted mulberry genotypes for sericulture and to estimate connections between leaf compound and silkworm performance parameters. A controlled feeding experiment of silkworms was performed to test the influence of leaves from selected trees on the growth of larvae, the health and microbiological status of larvae (e.g., gut bacterial microbiome, Bombyx mori nucleopolyhedrovirus infection), weight of cocoons and raw silk parameters. The Slovenian and Hungarian mulberry genotypes had significantly higher total protein contents, and lower total phenolic contents and differed significantly in some individual phenolics compared to the reference sericultural and fruit varieties. Significant differences were found in the contents of the macro- and microelements, namely S, Mn, Fe, and Sr. Based on correlative statistics and multivariate analysis, a combined positive influence of proteins, specific phenolics, and microelements on larval growth and silk thread parameters was predicted. The results of the study indicate that selected local Slovenian and Hungarian mulberry varieties are suitable for high-quality silk cocoon and raw silk production.

An In-Depth Insight into the Profile, Mechanisms, Functions, and Transfer of Essential Amino Acids from Mulberry Leaves to Silkworm Bombyx mori L. Pupae and Fish

“…This value allows us to speculate that pupae may transform into an alternative source of nutrition for other species. Significant qualitative and quantitative differences in biochemical characteristics linked to proteins, phenolics, and minerals were found when genetically European mulberry cultivars were compared [31]. Using multivariate analysis, Krajnc et al [31] defined distinct chemotypes and evaluated them according to the composition of single AAs and phenolics.…”

“…Significant qualitative and quantitative differences in biochemical characteristics linked to proteins, phenolics, and minerals were found when genetically European mulberry cultivars were compared [31]. Using multivariate analysis, Krajnc et al [31] defined distinct chemotypes and evaluated them according to the composition of single AAs and phenolics. The information would be helpful in selecting and growing the best native European cultivars with a high concentration of vital AAs and a particular phenolic component.…”

“…Since mulberry leaves are the unique feed source available to silkworms, they are an essential source of nutrition. There are still gaps in the knowledge regarding flow analysis up to the use in fish, with a focus on AAs, despite publications on the chemical composition or phyto-chemical, pharmacological, and toxicological effects, or on the biochemical variances depending on the types [29][30][31].…”

The Darker the Better: Identification of Chemotype Profile in Soroses of Local and Introduced Mulberry Varieties with Respect to the Colour Type

“…Total phenolic compounds were determined spectrophotometrically, according to Urbanek Krajnc et al [62]. Samples (2 ± 0.2 g) were extracted in 4 mL 95% methanol, incubated 30 min at room temperature in the dark and then centrifuged.…”

“…During our inventory of mulberry trees in different regions of Slovenia and Hungary, shoots of historical trees were taken for propagation in order to establish a mulberry collection and to investigate the genetic and biochemical characteristics of the existing mulberry gene pool. The screening of metabolites in the leaves allowed us to define superior genotypes of the local gene pool that have already proven their potential as forage [60][61][62].…”