Effect of aqueous neem seed extract via irrigation on larvae of Liriomyza sativae in melon crop

Abstract

The leafminer [Liriomyza sativae (Diptera: Agromyzidae)] is one of the main pests of melon crop (Cucumis melo) in the states of Rio Grande do Norte and Ceará. Thus, adopting strategies to control this destructive insect is essential. The aim of this study was to evaluate the effect of aqueous neem seed extract, applied to soil via irrigation, on leafminer larvae, in the melon crop. An experiment was conducted in greenhouse, in completely randomized design, consisting of five treatments (four doses of aqueous neem seed extract: 1; 3; 5 and 10 g/100 mL) and the control consisting only of distilled water and 10 replicates (melon plants). The treatments were applied in a single dose, via soil irrigation. In the first stage of the evaluation, 24 hours after application, the number of dead larvae per plant was counted. In the second step, pupal mortality was recorded. The total mortality was also calculated considering the number of larvae and the number of emerged adults. We verified that, increasing the concentration of aqueous neem seed extract, an increase in the larval and pupal mortality of the leafminer in melon crop was noticed. The concentration 10 g/100 mL presented the best results, resulting in 36.4% of larval mortality, 96.5% of pupal mortality and 96.8% of total mortality.

Toxicity of Alone and Combine Application of Botanical Extracts against 2nd Instar Larvae of Liriomyza trifolli on Tomato, Lycopersicum esculentum

“…The larval mortality percentage was increased with an increase in chemical concentration. Costa et al (2018) had reported similar findings. It was observed that alone and combine application proved the best strategy to control leafminers.…”

Toxicity of Jatropha and Neem Oil Combination on Pink Hibiscus Mealybug

“…Azadiractin is the active ingredient in A. indica responsible for the insecticidal activity of this plant, acting through the physiological processes of the insects in the regulating hormones of metamorphosis, compromising the normal development of insects both in the larval and pupal stages, which can result in mortality of individuals [11,18], in addition to this component, neem still has triterpenoids such as nimbine and salanine, however these compounds have little effectiveness in controlling insects [19]. Sami et al [20] by exposing adult insects and larvae of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) to raw neem powder, showed a significant reduction in the weight of insects and an increase in the mortality rate.…”

“…Neem has azadiractin as its main compound extracted from its fruits, which interferes with the functioning of animals' endocrine glands [10]. Studies report that the aqueous extract of the seeds of A. indica has insecticidal activity with 96.5% mortality in pupae of Liriomyza sativae (Diptera: Agromyzidae) [11]. Vieira and Peres [12] also found mortality levels of 98.5% after spraying neem extract at a concentration of 2% over Brevicoryne brassicae L. (Hemiptera: Aphididae).…”

Essential oils on the control of melon leafminer

“…Several researchers have emphasized the importance of bioactive extracts from plants as a strategy for the control of agricultural pests. These products are usually composed by terpenoid, sesquiterpenes and detones (HIKAL et al, 2017;COSTA et al, 2018;IKBAL and PAVELA, 2019;KLEIN et al, 2020;FOLKOWSKI et al 2020;ISMAN, 2020).…”