Molecular Entomology, 2025, Vol.16, No.1, 28-38 http://emtoscipublisher.com/index.php/me 34 shows that organic practices can alleviate the environmental pressure on bees, allowing them to invest more energy in growth and reproduction rather than detoxification and immunity. This reduction in pressure may have a cumulative effect on evolution: selecting traits that are more conducive to growth and reproduction. Bee populations that have been in an organic environment for a long time may tend to retain genotypes that perform well under low pesticide conditions, such as strategies that invest more resources in reproduction. On the contrary, in a high-pressure pesticide environment, they may prefer to retain genotypes that are more resistant to toxicity but slightly inhibited in reproduction. Figure 2 Genetic variation in metabolic resistance to clothianidin in honey bees (Adopted from Tsvetkov et al., 2023) Image caption: Metabolic differences in the response to clothianidin exposure between two P450 genotypes of honey bee CYP9Q1 and CYP9Q3; bees with different genetic backgrounds (represented by green, red, and blue DNA strands) produce offspring through hybridization. When exposed to clothianidin, the offspring exhibit varying survival abilities: some survive while others die (Adopted from Tsvetkov et al., 2023) 5.3 Research on the impact of transgenic crop planting on bee genetic diversity With the large-scale promotion of transgenic insect-resistant and disease-resistant crops, people are also concerned about their potential impact on pollinating insects. Transgenic crops mainly affect bees in two ways: one is the direct effect, that is, bees ingest exogenous products expressed in pollen and nectar of transgenic plants; the other is the indirect effect, that is, transgenic crops change agricultural production methods, thereby affecting the habitat and resources of bees. For example, Bt crops (transgenic varieties expressing Bacillus thuringiensis toxins) can kill lepidopteran pests that feed on their tissues, but whether bees are affected by feeding on Bt pollen has been controversial. Compared with direct effects, the indirect ecological effects of transgenic crops may be more worthy of attention. For example, the large-scale application of herbicide-resistant genetically modified crops is often accompanied by more herbicide use, which eliminates weeds and wildflowers in the fields. This undoubtedly reduces the non-crop flower sources for bees, which is equivalent to amplifying the nutritional pressure of monoculture on bees. In the vast genetically modified soybean and corn belts in the United States, due to the widespread use of herbicides, weed flowers in fields and ridges are almost extinct, which is considered to be one of the reasons for the decline in monarch butterflies and pollinating insects. Similarly, for bees, the continued lack of flower sources will exert nutritional selection pressure on their populations, which may force bees to adjust their reproductive strategies (such as reducing the number of overwintering bees) to adapt to the resource-scarce season. 6 Conservation and Management Strategies for the Impact of Agricultural Practices on the Evolution of Bee Populations 6.1 Strategies to reduce the evolutionary pressure of pesticide use on bees Given that pesticides are one of the primary pressures faced by pollinators such as bees, reducing the selection pressure exerted by pesticides on bees is one of the key goals of conservation strategies. First, the reduction and precision of pesticide use should be promoted. Through methods such as integrated pest management (IPM), the
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