关键词: 宽胫夜蛾, 性信息素类似物, 化学合成, 生物活性, 化学调控昆虫行为

Abstract:

【Background】In recent years, with the significant increase in the area planted with the newly introduced crop quinoa, Protoschinia scutosa, which prefers quinoa, has gradually increased and become a major pest of quinoa, posing a potential threat to the production of agriculture in China.【Objective】The objective of this study is to synthesize two different types of analogues modified with the polar group of the sex pheromone (Z)-hexadec-11-en-1-yl acetate (Z11-16:Ac), as the parent structure, and determine the biological activity, providing a theoretical basis for using sex pheromones and analogues for the green control of P. scutosa.【Method】The sex pheromone precursor (Z)-hexadec-11-en-1-ol (Z11-16:OH) was used as the raw material, and triethylamine was used as the acid-binding agent (4-dimethylaminopyridine was added as the catalyst for the reaction with the anhydride), and the esterification reactions with 2-bromopropionyl chloride, 2-chloroacetyl chloride, difluoroacetic anhydride, trifluoroacetic anhydride, methacryloyl chloride, and 2-butenoyl chloride were carried out respectively, the halogen atom modified analogues (K1-K4) and carbon chain end double bond modified analogues (K5-K6) were synthesized, separated and purified by column chromatography. Different concentrations (0.001, 0.01, 0.1, 1, 10, 100 μg·μL^-1) of sex pheromone analogues (K1-K6) were prepared by gradient dilution. The EAG response values of analogues K1-K6 were measured by direct stimulation on the male tentacles of P. scutosa using different concentrations of analogues. Sex pheromone analogue trap lures were prepared by adding different doses of analogues to the sex pheromone. The field trapping trials were conducted in the summer of 2021 in Yanqing, Beijing, and the analogue activity was analyzed by counting the male moth in the traps.【Result】As the stimulation concentration increased from 0.001 to 100 μg·μL^-1, the electrophysiological response values of male tentacles to analogues K1 to K5 showed a gradual increase trend. Male tentacles responded most strongly to the compound (Z)-hexadec-11-en-1-yl 2-bromopropanoate (K1), with a response value of 1.34 mV at 100 μg·μL^-1. The EAG activities of analogues K5 and K6 were relatively poor, with EAG response values of 0.67 and 0.57 mV at 100 μg·μL^-1, respectively. All the six analogues synthesized showed good biological activity in field trapping experiments. K5 had the highest average trapped number of 35.00 heads at an additive level of 100 μg, which was significantly higher than the sex pheromone control. The average number of trapped adults of analogue K1 was 32.33 heads at an additive level of 10 μg during the whole period (15 d) of field trapping tests, which was significantly higher than the sex pheromone control.【Conclusion】The analogues K1 and K5 showed potentiation activity and can be used as potentiators of sex pheromones as verified by EAG and field trials. The addition of different doses of analogues K2, K3, K4 and K6 exhibited comparable activity to sex pheromones. This study provides a scientific and theoretical basis for the green control of P. scutosa.

Key words: Protoschinia scutosa, sex pheromone analogue, chemical synthesis, bioactivity, chemical control of insect behavior