Data availability_Paper Synergism between Cry1 and Vip3Aa

Description

These data comprise a complete set of toxicological bioassays conducted with neonate larvae of the caterpillar Spodoptera cosmioides (an agricultural pest), using insecticidal proteins derived from Bacillus thuringiensis (Bt) — specifically the Vip3Aa, Cry1Ba, Cry1Ca, and Cry1Ea toxins. The experiment investigates the toxicity of these proteins both individually and in binary combinations (mixtures of two proteins). The data are organized into five complementary files.

Steps to reproduce

1. Protein production and preparation The insecticidal proteins Cry1Ba, Cry1Ca, Cry1Ea, and Vip3Aa were produced using recombinant Escherichia coli clones previously developed by the research group. Induction of these clones allowed the expression of the target proteins, which were then: Visualized on SDS-PAGE gels to confirm presence and correct molecular weight; Quantified to determine the exact protein concentrations for use in bioassays. 2. Preparation of contaminated artificial diet Bioassays were conducted with neonate larvae (newly hatched) of Spodoptera cosmioides, maintained in laboratory-established colonies. The basal artificial diet used was the Greene et al. (1976) diet, widely employed for rearing Lepidoptera under controlled conditions. Purified proteins were directly incorporated into the artificial diet at different concentrations. For each individually tested protein, diets were prepared with increasing concentrations (e.g., 0.5, 1, 5, 25, 50, 250, 500 ng/cm² for Vip3Aa, or 25, 50, 100, 200, 400, 800, 1600 ng/cm² for Cry1Ba, etc.). For binary combination assays, both proteins were added simultaneously to the diet at the corresponding concentrations. 3. Toxicity bioassay The experimental design followed a completely randomized design, with: 3 biological replicates per concentration; 16 neonate larvae per replicate (totaling 48 individuals per concentration); Control group (protein-free diet) to assess natural mortality. Larvae were individually placed in containers with the treated diet and maintained under controlled conditions of temperature, humidity, and photoperiod (typical for insect bioassays, e.g., 25 ± 2 °C, 60–70% RH, 12–14 h photophase). After an exposure period (usually 5 to 7 days), live and dead larvae were counted for each replicate. 4. Data analysis Percentage mortality was calculated for each replicate and, when necessary, corrected for control mortality using Abbott's formula. Data were subjected to arcsine square-root transformation: square root X/100 ​for variance stabilization, as indicated in the tables. For estimating lethal concentrations (LC50, LC90, etc.), the pooled dose-response data (File IV) were analyzed using Probit or Logit regression with specialized statistical software (e.g., SAS, R, or PoloPlus). Finally, the evaluation of combination effects (synergism, antagonism, or additivity) was performed using appropriate interaction models (e.g., Colby's method or deviation analysis).

Institutions

• Universidade Estadual Paulista (Unesp)

  São Paulo, São Paulo

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