Semiochemicals from coccinellid beetles modulate feeding attributes, reproductive parameters and antioxidant enzyme activities in Parthenium beetle, Zygogramma bicolorata Pallister
Abstract
Parthenium is a toxic invasive weed that widely infests agroecosystems worldwide. It hosts both phytophagous chrysomelid beetles used as biocontrol agents and the predaceous coccinellid beetles. This study evaluated reproductive traits, nutrient assimilation, and antioxidant enzyme activities of the Parthenium beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) in the presence of semiochemical tracks left by coccinellid beetles. Results revealed that the presence of coccinellid semiochemical tracks on the weed significantly reduced fecundity and egg viability in Z. bicolorata females. Age-specific fecundity and egg viability followed a triangular pattern, with exposed females reaching peak oviposition and maximum egg viability earlier than unexposed females. Females exposed to semiochemical tracks also showed lower assimilation of triglycerides, glucose, and proteins compared to those not exposed. Triglyceride assimilation increased with age, whereas glucose and protein assimilation declined. Activities of superoxide dismutase (SOD) and catalase (CAT) were higher in the absence of semiochemical tracks, while lipid peroxidation (LPO) was elevated in their presence. SOD and CAT activities initially increased with age in both control and experimental setups, but declined in older females. In contrast, LPO activity increased initially and then declined with age in the control group, but continued to rise with age in the experimental setups. The feeding deterrent effects of semiochemical tracks were species-specific. Overall, these findings indicate that coccinellid semiochemical tracks on Parthenium interfere with the biological control efficacy of Z. bicolorata females.
Dataset DOI: 10.5061/dryad.0vt4b8hc7
Description of the data and file structure
This study examined the effects of heterospecific semiochemical tracks—chemical cues deposited by the coccinellid beetles Coccinella transversalis and Menochilus sexmaculatus—on the physiological and reproductive performance of female Zygogramma bicolorata Pallister, commonly known as the Parthenium beetle. Specifically, the study evaluated the impact of these chemical cues on female fecundity and egg viability over a 40-day period following exposure to semiochemical tracks left by either C. transversalis or M. sexmaculatus.
In addition to reproductive parameters, nutrient assimilation in females was assessed by measuring triglyceride, protein, and glucose levels on the 10th, 20th, 30th, 40th, and 50th days post-adult emergence. The activities of key antioxidant enzymes—superoxide dismutase (SOD) and catalase (CAT)—were also quantified, along with lipid peroxidation (LPO) levels as an indicator of oxidative stress. All physiological and biochemical measurements were conducted under the same semiochemical exposure conditions.
Files and variables
File: Data.xlsx
The dataset is provided in a file entitled Data.xlsx and consists of two worksheets:
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Reproductive data: This dataset contains records of female fecundity (number of eggs laid per day) and egg viability (number of viable eggs per day) over a 40-day period under three experimental conditions: exposure to tracks left by M. sexmaculatus (MS), exposure to tracks left by C. transversalis (CT), and a control group with no semiochemical exposure.
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Biochemical and enzymatic data: This worksheet includes measurements of nutrient assimilation (triglycerides, proteins, and glucose expressed in mg/ml) and oxidative stress markers (SOD, CAT, and LPO expressed in U/mg) in females sampled on days 10, 20, 30, and 40 under MS, CT, and control conditions.
Elucidating the role of semiochemical communication in regulating these physiological and reproductive processes offers valuable insights into the chemical ecology of Z. bicolorata. Furthermore, these findings may contribute to optimizing the use of this beetle as a biological control agent against Parthenium hysterophorus, a highly invasive weed.