Abstract:
African giant snail (Achatina achatina) is known as a serious pest of
seedlings and leaf vegetables throughout the world including Sri Lanka.
Their nocturnal and hiding behavior make them very difficult to be
controlled using conventional pest control methods. Present preliminary
study aimed to find out the potential use of the extracts of two spices
namely garlic and ginger as feeding deterrents for A. achatina. Snails
hatched from one egg clutch with body weight ranged from 3.3 to 4.9 g
were used in the study. They were divided as the control group, garlictreated
group and ginger-treated group using 21 snails. The snails were
daily fed with fresh tree spinach leaves (Talinum paniculatum) treated with
distilled water (control) and either 2.5% aqueous extracts of garlic or
ginger. Leaf area was measured by Planimeter before the treatment and one
day after feeding. Body weights of experimental snails were recorded in 72
hrs. intervals from June 2018 to October 2018. The results reveals that the
snails do not prefer to feed on leaves treated with aqueous extracts of both
garlic and ginger and percentage feeding preference for garlic (66.67%) and
Ginger (45.0%) was lower than that of the control (78.72%). At the end of
the experiment (66th day), mean body weight of snails which fed on garlic
treated leaves (3.21 g) was lower compared to the mean body weights of
those fed on ginger treated leaves (3.6667 g) and the control (4.6033 g).
Findings of the present study indicate the possible use of garlic extract as a
feeding deterrent for A. achatina and further studies are needed to assess
the effects of these extracts at field level.