Effects of Irradiation on the Mediterranean Meal Moth, Ephestia Kuehniella Zeller, Cultured on ⁸⁹Sr-spiked Food

Summary

Ephestia kuehniella Zeller was cultured on corn-meal spiked with ⁸⁹Sr at concentrations of 0, 0·1, 0·3, 1·0, 3·0 and 5·0 µc/g of food.

As the environmental radiation was increased, the adults which were subjected throughout their life-cycle produced progressively fewer progeny.

5·0 µc ⁸⁹Sr/g food approaches the critical level which will inhibit population development.

Life-span of the adults was not influenced by the experimental conditions.

Delayed development occurred at all isotopic concentrations employed.

The radiostrontium-content of females at the end of their life-cycle was half that of males. Twenty-four hours after eclosion, the radioactivity of the female moth was equal to, or greater than, that of corresponding males. Reproductive metabolism is offered in explanation.

At the two highest culture levels (3 and 5 µc ⁸⁹Sr/g), the increased number of males (homogametic sex) over females (heterogametic sex) is consistent with the radiation genetic effect of induced recessive lethals. No selective radiation effect upon the sexual capacity of gametes of the F₁ was indicated, since the subsequent F₂ sex ratio was 1 : 1.