Influence gamma Irradiated on some biological aspects of predator mite Cheyletus malaccensis (Oudemans) (Trombidiformes: Cheyletidae)

Abstract

Due to the problems caused by mite pests in agricultural crops, the modern trend in controlling these pests is to search for a safe control program that includes mite predators and enhances their capabilities. Therefore, the aim of this research was to study the effect of use gamma rays with low doses (2, 4, 6 and 8 Gy) on female and male vitality predatory mite Cheyletus malaccensis. Three experiments were conducted, the first involved exposing a female to radiation and then mating her with a normal male. The second involved mating irradiated males with normal females. The third involved mating irradiated females with irradiated males. All three conditions were compared with the control (non-irradiated) condition. The biological aspects of the predatory mite were monitored and measured, and the results showed that its life cycle and age were significantly shortened when exposed to low radiation doses (2 and 4 gray), which leads to an increase in the number of generations in the three cases, extending the egg-laying period, increasing the number of eggs, and increasing the predator’s ability to prey. The effect of radiation on females exposed to radiation increases the lifespan of females in the first and third cases, while in the second case it remains unaffected compared to the control. Meanwhile, the lifespan of males exposed to radiation increases in the second and third cases, while in the first case it remains unaffected compared to the control. The female sex ratio was greater than the male sex ratio in the first and third cases of females exposed to radiation, while the male sex ratio was greater than the female sex ratio in the second case compared to the control. The daily egg production rate also increased compared to the control. This indicates a significant number of acarid predators, and this represents a success in biological control, a trend we are pursuing.