Research on population monitoring and biology of snail predator Rumina decollata (L.) (Gastropoda: Subulinidae) and its alternative prey Eobania vermiculata (M.) (Gastropoda: Helicidae) in citrus fruits

In this study, the population of Eobania vermiculata (M.) (Gastropoda: Helicidae), which has been a pest on citrus fruits in recent years, and Rumina decollata (L.) (Gastropoda: Subulinidae), which is a snail predator, was monitored and the most preferred foods were determined when E. vermiculata was offered as prey and only lettuce, potato, spinach, carrot, cabbage, orange, grapefruit, lemon, lettuce X E. vermiculata and lettuce X orange X E. vermiculata combinations were offered as alternative food. Population monitoring was carried out in two Meyer orchards of different ages, each with an area of 100 da, in which 300 R. decollata were released and the counts were made once a month by counting above or underneath the canopy of 100 trees.. As a result of the study, the highest population density of E. vermiculata was found in January 2024 in the 10-year-old orchard with 10.84 indivuals per tree above or below the canopy. In the three-year-old Meyer lemon orchard, 70.60 indivuals per tree were recorded in the May 2023. The experiments and rearing studies were carried out in a climate room at 21±2°C temperature, 65±5% RH, and light conditions of 16:8 hours (light:dark). Transparent sealed storage containers with a size of 11x12x4 cm were used for the trials. Each experiment was set up as 20 replicates and observed three days per week for one year to determine the annual consumption of prey snail, egg production and most preferred plant products of R. decollata on E. vermiculata. After hatching, daily (3, 6, 12, 24, 48, 75, 96, 120 and 240) growth measurements (mm) were taken in relation to the different feeding sources. R. decollata showed the best development in the 240-day measurements with an average of 31.75±0.66 when fed with lettuce x E. vermiculata. It showed the weakest development with an average of 13.88±0.82 when fed with spinach.