Effectiveness of metaldehyde Lumakidin® against snails and slugs in the greenhouse of Spathiphyllum and lettuce field and its comparison with the efficiency of Ferricol® and Sabzarang® in ornamental flower greenhouse

Snails and slugs as terrestrial molluscs are the important pests of greenhouses and lettuce fields, which cause destruction by feeding on the leaves, stems, roots, and seeds of plants. Using molluscicides is the most important control method against their damages. Metaldehyde is considered as one the most important chemical compounds which is widely used to control slugs and snails. Lumakidin 5G® (Basir Shimi Company), as a product containing metaldehyde, has been at field recommended dose, 2g/m2, while its 0.7g/m2 has the potential to control slugs and snails according to the manufacturer. Ferricol® is bait including 1% iron phosphate, and Sabzarang® is snail repellent paint containing insoluble copper salts, special sticking, and binding agents. So far, no research has been conducted on the effectiveness of Lumakidin 5G®, Ferricol® and Sabzarang® in the ornamental flower greenhouse against snail/slug. Therefore, this study aims to evaluate the efficiency of Lumakidin 5G®, Ferricol®, and Sabzarang® in the ornamental greenhouse of Spathiphyllum wallisii in Guilan province, along with the effect of Lumakidin 5G® at 0.7 and 2 g/m2 in lettuce in Lactuca sativa field in Mazandaran province.

Treatments included 1, 2: Lumakidin 5G® at two doses of 0.7 and 2 g/m2, 3: Ferricol® (5g/m2), 4: Sabzarang®, and 5: control (untreated) against slug/snail in the ornamental greenhouse of S. wallisii during 2018 and 2019. In greenhouse, Lumakidin 5G® and Ferricol® were applied between the pots, and Lumakidin 5G® in lettuce field was used between the rows. The pots were painted with Sabzarang®, as a 10 cm wide band, to prevent the snails from climbing the plants. In addition, the effectiveness of Lumakidin 5G® at 0.7 and 2g/m2 was evaluated in the lettuce, L. sativa field. The number of live slugs/snails was counted one day before and 2, 4, 8, 14, and 21 days after the treatments. During the 21st day after the treatment, the percentage of leaves damaged by snails/slugs in the greenhouse and the percentage of damaged plants in the lettuce field in Lumakidin 5G® treatment were calculated.

Based on the two-year results of the greenhouse, Lumakidin 5G®, doses of 2 and 0.7 g/m2, Ferricol® and Sabzarang® caused 80.9, 69.9, 68.1, and 65.7% mean efficiency against slug, Deroceras agreste, respectively. Mean comparison indicated that Lumakidin 5G® (0.7 g/m2), Ferricol® and Sabzarang® failed to have a statistically significant difference, while Lumakidin 5G® (2g/m2) was significantly more effective than the other three treatments. Under these conditions, the mean comparison of two doses of metaldehyde in the annual statistical analysis on the twenty-first day showed no statistically significant difference. In the lettuce field, the application of doses of 0.7 and 2g/m2 Lumakidin 5G® against slug, D. agreste in two years of experiment had a similar trend. Thus, more efficiency of higher doses was observed in the first and second year of the experiment up to 8 and 4 days, respectively, while similar efficiency of both doses was evident in the following days, which low-dose of Lumakidin 5G® (0.7 g/m2) can be as effective as the recommended dose (2g/m2) against the slug. The percentage of leaves damaged by snails/slugs in the greenhouse and the percentage of damaged plants in lettuce field in Lumakidin 5G® treatment showed the effective role of both doses in reducing the damage. The use of this compound in both greenhouse and field conditions reduced plant damage about 3 to 4 times compared to the control.

Due to the effectiveness of Lumakidin 5G® (at 0.7 g/m2), it is recommended to be used in the greenhouse and field to reduce snails/slugs damage. The application of this product decreases the cost of control by reducing the amount of consumption per m2/hectare. Further, it can have less environmental pollution than other doses. In organic agriculture, the use of Ferricol® is recommended due to the environmental safety of the compound. However, it is more expensive than metaldehyde. Thus, it can be considered as a good choice for a greenhouse due to its smaller scale than the field. Sabzarang®, as a repellent color, can be another alternative to chemicals, but the compound does not kill snails/slugs and only keep them away from that area. Finally, the paint is more expensive than the other two compounds.