EFFECT OF PESTICIDES ON THE DEVELOPMENT OF OOCYTES AND SAC EGGS OF Alpaida veniliae (ARANEAE, ARANEIDAE)

GONZALEZ ALDA, BENAMÚ MARCO, SCHNEIDER MARCELA

Montevideo

Congreso; 22nd International Congress of Arachnology; 2023

International Society of Arachnology- Universidad de la República

Transgenic crops and their expansion have generated a significant increase in the use ofbroadspectrum pesticides, which are very toxic for most natural enemies, especially arachnids.Alpaida veniliae (Araneae, Araneidae) is a weaver spider, abundant in soybean and rice crops,and feed on many insect pests. Sublethal effects of various pesticides (cypermethrin,endosulfan, spinosad, methoxyfenozide) and the herbicide glyphosate on the development ofoocytes, the sac eggs and eggs were evaluated. Sublethal concentrations of the products wereapplied by ingestion of Musca domestica treated by immersion. The prey was provided for 4consecutive days. After 21 days post-treatment females were mated, and the dissection of theovaries was conducted 15 days post-copulation. There was an abnormal development ofoocytes in cypermethrin, endosulfan, spinosad and glyphosate treatments compared to thecontrol group, with a smaller development and the presence of fat aggregates. The egg sacbuilding of was also abnormal in these treatments. Some of the eggs were found in poorcondition or dehydrated. Methoxyfenozide had no effect on the development oocytes and sacseggs. The results show a negative impact of sublethal concentrations of many insecticides, twoof them belonging to conventional pesticides and the herbicide glyphosate on A. veniliae. Thisstudy shows that not only important to assess mortality, but other aspects related toperformance, such as fertility, which are directly linked to its effectiveness for pest control.