Sort:
Issue
Correlation among digestive enzyme and detoxification enzyme activities and growth and development, nutritional effects in Hyphantria cunea larvae
Journal of Central South University of Forestry & Technology 2025, 45(9): 196-205
Published: 25 September 2025
Abstract PDF (2.3 MB) Collect
Downloads:7
【Objective】

This study aims to investigate the changes in digestive and detoxification enzyme activities, growth and development, and nutritional effects in the 4th-6th instar larvae of Hyphantria cunea after feeding on various host trees. It also seeks to analyze the adaptation mechanisms of H. cunea to different host trees.

【Method】

The 4th-6th instar larvae were raised indoors on the leaves of Ulmus pumila, Juglans mandshurica, Tilia amurensis, Salix matsudana, Betula platyphylla, and Albizia kalkora. The correlation between the activities of digestive enzymes (α-amylase, lipase, trypsin) and detoxification enzymes (glutathione-S-transferase (GSTs), acetylcholinesterase (AchE), carboxylesterase (CarE)) and their growth, development, and nutritional effects were analyzed.

【Result】

1) As the instar stage increased, the midgut α-amylase activity significantly decreased, while lipase activity significantly increased. Trypsin activity initially decreased and then increased. GSTs and AchE activities decreased, with a notable decline in AchE, whereas CarE activity first decreased and then increased; 2) No significant correlation was observed between midgut α-amylase activity in the 4th-6th instar larvae and GSTs activity in the 5th-6th instar larvae. However, GSTs activity in the 4th instar larvae showed a significant correlation with growth and development indicators, except for food intake; 3) Except for α-amylase and GSTs, the activities of other enzymes in the 4th-5th instar larvae were significantly positively correlated with body weight, body length, head width, food intake, food utilization rate, and conversion rate, but negatively correlated with food consumption rate; 4) In the 6th instar larvae, growth and development indicators were only significantly correlated with CarE activity, with body length, food utilization efficiency, and conversion rate being positively correlated, and food consumption rate being negatively correlated.

【Conclusion】

The enzyme activity of H. cunea larvae varied after feeding on six host trees. By regulating enzyme activity, H. cunea larvae can control nutrient absorption and utilization, allowing for normal growth and development. This regulation also enhances their adaptability to different host trees and expands their host range.

Issue
Development of a piggyBac transgenic system in Bactrocera dorsalis and its potential for research on olfactory molecular targets
Journal of Integrative Agriculture (JIA) 2025, 24(6): 2311-2326
Published: 18 July 2024
Abstract PDF (6.6 MB) Collect
Downloads:13

Chemicals that modify pest behavior are developed to reduce crop damage by altering pest behavior, using specific genes within the olfactory system as molecular targets. The identification of these molecular targets in Bactrocera dorsalis, also known as the functional study of key olfactory genes, relies on CRISPR/Cas9-mediated gene knockout techniques. However, these techniques face limitations when applied to lethal genes. Transgenic technology offers a solution since it enables precise manipulation of gene expression in specific tissues or during certain developmental stages. Consequently, this study developed a piggyBac-mediated transgenic system in B. dorsalis to investigate reporter gene expression in olfactory organs, and assessed the olfactory behavior and antennal electrophysiological responses in transgenic lines. The goal was to assess the potential of this approach for future research on olfactory gene function. A universally expressed housekeeping gene from the BdorActin family was identified using the developmental transcriptome dataset. Its candidate promoter region (BdorActinA3a-1P–2k) was then cloned into the piggyBac plasmid. We subsequently established two stable transgenic lines with specific TTAA insertion sites on chromosomes 4 and 5, consistent with the characteristics of piggyBac transposition. The transgenic strains exhibited essentially normal survival, with hatchability and adult lifespan unaffected, although there were slight reductions in the emergence rate and oviposition capacity. The fluorescent reporter has been successfully expressed in olfactory-related organs, such as the antennae, proboscis, maxillary palp, legs, external genitalia, and brain. The antennal electrophysiological responses to representative chemicals in the transgenic lines were consistent with those of the wild type. However, some olfactory-related behaviors, such as pheromone response and mating, were significantly affected in the transgenic lines. These findings suggest that our system could potentially be applied in future olfactory research, such as driving the expression of exogenous elements that are effective in olfactory organs. However, caution is advised regarding its impact when applied to some olfactory-related behavioral phenotypes.

Total 2