|
چکیده
|
Tomato leaf miner, Tuta absoluta (Meyrick) is a key and dangerous pest of Solanaceaus plant in Iran. Larva of the pest cause damage on different parts of host plants including leaves, stems and fruits. Excessive use of chemical insecticides quickly leads to pest resistance. Using plant-based compounds such as seed extract for pests control are good alternatives to chemical insecticides. This experiment was carried out with 5 concentrations (0, 10, 15, 20, 25, 40, ppm) of the C. carvi seed extract determined using logarithmic distance. Five groups of 10 eggs of the pest were considered for each concentration. For this purpose, one or two tomato leaves containing eggs covered with wet cotton and foil (to prevent the rapid drying of the leaves) were placed in a Petri dish and sprayed with a handy sprayer containing certain concentration. The specimens were incubated at 25 ± 5 °C, 60 ± 5% RH and 16:8 h L:D and mortality and survival rates were recorded daily. The results indicate that the plant extract affected the eggs highly at LC50 = 23.22 and LC90 = 49.71 (Intercept ± SE= -1.038±.163, Slope ± SE= 4.30 ± 1.160). The results also showed that by increasing the extract concentration, survival rates decreased. In the present experiment, the C. carvi seed extract reduced the emergence of the T. absoluta larval population. Based on the findings, it is recommended to design further studied on the formulation aspects of the plant extracts in order to develop them through IPM programs in order to protect the environment and produce pesticide free crops.
|