Botanical pesticides

Pest control through integrated pest management systems stands as a very convenient sustainable hazard-free alternative to pesticides, which are a growing global concern if overused. The ability of the soprano pipistrelle bat (Pipistrellus pygmaeus) to control the rice borer moth (Chilo supressalis), which constitutes a major pest of rice around the world, was studied in the Ebre Delta, Northeastern Iberia. Evidence was found on the ability of this particular bat species to control borer infestations: a) the moth was consumed during at least the last two peaks of the moth activity, when most crop damage is done; b) the activity of bats significantly increased with moth abundance in the rice paddies; c) the pest levels have declined in the study area (Buda Island, Eastern Ebre Delta) after the deployment of bat boxes and their subsequent occupation by soprano pipistrelles. The value of the ecosystem service provided by bats was estimated at a minimum of 21€ per hectare, equivalent to the avoided pesticide expenditure alone. We suggest that this natural service can be enhanced by providing bat populations with artificial roosts in rice paddies were some key ecosystem features are present.

ABSTRAK
Penggunaan pestisida kimia menyebabkan berbagai masalah yang berkaitan dengan kelestarian lingkungan dan kesehatan manusia. Oleh karena itu, penggunaan pestisida berbahan baku alami merupakan salah satu alternatif yang digunakan untuk mengendalikan organisme pengganggu tanaman (OPT). Brotowali (Tinospora crispa) merupakan tanaman berkhasiat obat yang tumbuh di daerah tropis termasuk Indonesia. Tanaman tersebut sering digunakan sebagai obat untuk demam, kolera, rematik, penyakit kuning dan diabetes tipe II. Bahan aktif yang terkandung di dalam akar, batang, daun, buah dan bunga brotowali, yang dapat mengendalikan OPT di antaranya adalah alkaloid, tanin, saponin, glikosida, terpenoid dan flavonoid beserta turunannya. Selain bersifat toksik untuk serangga, tanaman brotowali juga bersifat antijamur, antinematisida dan antimoluska. Batang brotowali dapat dimanfaatkan untuk mengendalikan serangga diantaranya tungau, Spodoptera exigua, Nephotettix spp, Nilaparvata lugens, Plutella xylostella, Phyliotera sinuata Ateph, Scirtothrips dorsalis Hood, Phyllocnistis citrella Stainton dan larva nyamuk Culex quinquefasciatus (vektor penyakit filariasis) dengan nilai efektivitas diatas 50% dan rasio efisiensi biaya produksi yang lebih rendah dari pestisida sintetik. Selain itu juga brotowali dapat digunakan sebagai bahan untuk campuran pestisida organik. Budidaya brotowali cukup mudah, walaupun belum banyak diteliti, sehingga ketersediaan bahan baku juga dapat berkelanjutan. Review ini bertujuan untuk mengemukakan hasil-hasil penelitian yang terkait dengan penggunaan brotowali sebagai bahan untuk pestisida nabati.

Kata kunci: Tinospora crispa, pestisida nabati, metabolit sekunder

ABSTRACT
Excessive use of chemical pesticides cause various problems related to environmental sustainability and human health. Therefore, the use of pesticides made from natural materials, such as from plants known as botanical pesticides, is one of the alternatives used to control plant pest. Bitter grape (Tinospora crispa) is a medicinal plant grows in tropical regions including Indonesia. The plant is often used as medicine for fever, cholera, rheumatism, jaundice and type II diabetes. The active ingredients contained in the roots, stems, leaves, fruits and flowers of this plant, which are able to control pests, are alkaloids, tannins, saponins, glycosides, terpenoids, flavonoids and their derivatives. Besides being toxic to insects, bitter grape also has antifungal, antinematicidal and antimollusca activities. The extract or directly used of bitter grape stem had been utilized to control insects such as mites, Spodoptera exigua, Nephotettix spp, Nilaparvata lugens, Plutella xylostella, Phyliotera sinuata ateph, Scirtothrips dorsalis Hood, Phyllocnistis citrella Stainton and larvae of Culex quinquefasciatus (phyllariasis disease vector), with the pesticide effectiveness above 50% and efficiency ratio of cost production lower than synthetic pesticide. Moreover, it can be mixed with other plants as raw materal for organic pesticide. Bitter grape can be cultivated easily, although its cultivation technology has not been widely studied. Thus, the sustainability of the raw materials will not be a problem. This review aimed to present the results of research related to the use of bitter grape as the material for botanical pestiside.

The infestation of striped mealybug (Ferrisia virgata) is common in orchards causing large
scale harms to fruit quality as well as quantity. A water-based insecticide was not proved effective to
control the mealybugs due to the presence of waxy outer coating. 30 percent ethyl alcohol was added
in order to make the herbal preparations effective. Clerodendron sp., Cymbopogon citratus, Pongamia
pinnata and Azadirachta indica extracts were tested for management of Ferrisia virgata. A 25%
concentration of Cymbopogon leaf extract was found as a most effective eco-friendly management
tool and safe herbal pesticide having no harmful effect over the experimental plants as well as on
other plants.

Biodeterioration of seeds due to fungal infestation cause considerable losses in terms of their viability, chemical composition and end-use. Control of such fungi using synthetic fungicides has limitation of adverse health and environmental consequences. This can be overcome through persistent exploration and promotion of eco-friendly botanical fungicides. With this milieu, methanolic extracts of wood, bark and seeds of Capparis decidua, traditionally acclaimed for medicinal value were evaluated for antifungal efficacy against six seed-borne pathogenic fungal species causing severe deterioration to economically important seeds during storage. Methanol extracts of wood, bark and seeds of C. decidua showed very low MIC values against all the six fungi. Results indicated that extracts of all the three parts at all the tested concentrations were effective as compared to negative control. However, extracts of different parts exhibited varying degrees of inhibition. Extent of activity also differed with concentration of extracts used. Radial growth inhibition was minimum with extracts of all the three parts at 5mg/ml concentration and maximum at 100mg/ml. Among the treatments, bark extract was found more effective than that of seeds and wood. Growth inhibition with bark and seed extract at concentration of 25mg/ml was almost at par with the synthetic fungicide carbendazim. Further, growth inhibition of all the six fungi with 50 mg/ml concentration of extracts of the three parts is significantly higher as compared to carbendazim. The study thus revealed the promising antifungal efficacy of C. decidua.

In urban and peri-urban areas in West Africa, the cabbage Brassica oleracea L. (Brassica-ceae) is protected using repeated high doses of synthetic insecticides. After a brief description of available IPM components, this paper presents a literature review focused on the botanical extracts that have been experimented with at the laboratory or in the field in West Africa against major cabbage pests. The literature reviewed mentions 19 plant species from 12 families used for cabbage protection in the subregion. The species most used are Azadirachta indica, Capsicum frutescens, Ocimum gratissimum and Ricinus communis. An overview of the world literature showed that a total of 13 plant species belonging to 8 families used to control cabbage pests are reported from the rest of Africa, and 140 plant species belonging to 43 families from the rest of the world. The most commonly used and tested plant species against insect pests in the three geographical areas considered is A. indica.

The toxicity of the extracts of three common tropical plants; Tobacco plant (Nicotiana tabacum), West African Black Pepper (Piper guineense) and Jimson weed (Datura stramonium) was evaluated on the larvae and pupae of Anopheles gambiae while the fumigation effect of the extracts was investigated on the adult mosquito. The concentrations of the extract used in the study were 0.1%, 0.2%, 0.4%, 0.8% and 1.0%. The extracts of the leaves of N. tabacum and seeds of P. guineense had significant larvicidal and pupaecidal effect on A. gambiae at 1hour and 24hours observation having LC 95 values of 0.67mL and 0.1mL for larvae and 0.19mL and 0.1mL for pupae respectively. However, only N. tabacum at 0.8% and 1.0% had significant adulticidal effect on the adult mosquito under 1hour observation. The extract of D. stramonium leaves had LC 95 value of 1.07mL for larvae and 0.91mL for the pupae. It was found to be least toxic to the larvae and pupae after 1hour and 24 hours observation period. It also had no lethal effect on the adult A. gambiae at all concentrations. It is inferred from the results obtained that the extracts used had some bio-active constituents, which resulted in the mortality effects.