Among the new contaminants relevant for environment, one of the most significant roles is played by pharmaceuticals like antibiotic products for either human or veterinary use. Their presence could cause serious damage to bacteria and microfauna, like nematodes. Within the widely investigated nematodes, very little is known about the interaction between antibiotics and entomopathogenic nematodes (EPN). EPNs have been used for biological control of crops, due to their ability to penetrate arthropod pests and kill their hosts thanks to a complex symbiotic mechanism with specific gram-negative bacteria. Tetracycline is an antibiotic used in human and veterinary medicine, both for therapeutic purposes and for the growth of livestock. Since its action against gram-negative bacteria is documented, we verified in this study the survival, growth and pathogenicity of two species of EPNs, Steinernema vulcanicum and S. feltiae. All tests were performed with tetracycline in 1% ethanol solution and up to 300 mg/L. Apparently, this incubation did not harm the vitality of EPNs. Both S. vulcanicum as S. feltiae recovered their vitality and entomopathogenic ability after 48 h. Moreover, the latter EPN species did not grow nor reproduce in the hemolymph of the Greater Wax Moth, Galleria mellonella, and their endosymbionts did not grow on MacConkey Agar. Our results suggest that the first EPN species has always retained all its abilities and that endosymbionts have acquired resistance to tetracycline, while experiments with the second EPN species provided some contrasting results in time that will require further investigations.

在与环境有关的新污染物中，最重要的作用之一是用于人类或兽医用途的药物，如抗生素产品。它们的存在会严重破坏线虫等细菌和微动物。在经过广泛研究的线虫中，对抗生素与昆虫病原线虫（EPN）之间相互作用的了解很少。由于具有特定的革兰氏阴性细菌的复杂共生机制，EPN能够穿透节肢动物害虫并杀死其宿主，因此已被用于作物的生物防治。四环素是一种用于人类和兽医学的抗生素，既可用于治疗目的，也可用于牲畜的生长。由于已记录了其对革兰氏阴性细菌的作用，因此我们在本研究中验证了其存活率，Steinernema vulcanicum和S. feeliae。所有测试均使用四环素在1％乙醇溶液中以及最高300 mg / L的条件下进行。显然，这种孵化并没有损害EPNs的生命力。既S. vulcanicum如S.氏线虫48小时后回收它们的活力和昆虫致病能力。此外，后一种EPN物种在大蜡蛾（Galleria mellonella）的大血飞蛾的血淋巴中既不生长也不繁殖。，并且它们的共生菌并未在MacConkey Agar上生长。我们的结果表明，第一个EPN物种一直保持所有能力，内共生菌对四环素具有抗性，而第二个EPN物种的实验及时提供了一些对比结果，需要进一步研究。