Application of plant extracts for pest management in tea: a study on tea leaf’s thrips, Scirtothrips bispinosus

Abstract

Medicinal plant extract contains bioactive molecules and these molecules are benefited to mitigate, eradicate or cure diseases. In advent to search for new medicinally important plant, the current paper deals to select the most effective and promising plants which are suitable for controlling tea leaf’s thrips (Scirtothrips bispinosus) based on extracts concentration and death affect over time. To fulfill the specific objectives, five medicinal plants extracts viz. Ipomoea crassicaulis, Lantana camara, Ipomoea hederaceaa, Glycosmis arborea, and Justicia gendarussa had been used with four different concentrations. From statistical analysis using One-way ANOVA and post hoc test, it was found that Ipomoea crassicaulis and Lantana camara are the most promising of all the experimented plants extracts based on both time and concentration. In the study, average mortality was found 0.47, 1.67, 1.93 and 2.53 for concentration of 1%, 5%, 10% and 15% respectively. Analysis based on different concentrations reveals that average mortality of thrips increases significantly with the increase of concentrations. Coefficient of variance was found minimum for Ipomoea crassicaulis and Lantana camara plants with range of 5.44 to 6.71 based on time and concentration. So, it could be concluded that these two plants are the most effective plants for controlling the tea thrips. For the other plants, ranks were found as Ipomoea hederaceaa, Glycosmis arborea and Justicia gendarussa respectively as well.
 J. bio-sci. 28: 87-93, 2020

Characterization of the complete mitochondrial genome of the new tea pest Mycterothrips gongshanensis (Insecta: Thysanoptera: Thripidae)

“…Thrips, a group of the signi cant pests of tea trees, distribute worldwide [1][2][3][4][5]. Although more than 20 species of tea thrips have been reported in China [6-8], only two species, Scirtothrips dorsalis Hood [9] and Dendrothrips minowai Priesner [3,10] had been being considered as the dangerous pests.…”

Lecanicillium lecanii (Zimmermann) Zare & Gams, as an efficient biocontrol agent of tea thrips, Scirtothrips bispinosus Bagnall (Thysanoptera: Thripidae)

“…Appropriate control measures have to be adopted for reducing the economic loss due to thrips infestation when the thrips population is around three thrips per shoot (Babu 2009). Different synthetic chemicals are being used for the control of this pest in south India, resulting in pesticide residue problem in made tea (Babu and Muraleedharan 2010;Azad et al 2020). Several species of natural enemies were reported to regulate the population of thrips in different cropping systems.…”

Molecular Diagnosis and Evolutionary Relationship Analysis Of Plant Parasitic Tea Garden Nematodes From Different Tea Estates In Sylhet Region of Bangladesh

“…In the tea cultivation area in Bangladesh, 71 insects, mite, and nematode species belonging to 45 families under 14 orders are recorded as pests of tea, and among them, 25.35% of species are foliar insects and mites, 26.76% are soil insects and nematodes, 21.13% are beneficial insects and 26.76% are butterflies. Different plant parts of tea such as leaf, root, stem, flower, and seed are affected by these pests of insects, mites, and nematodes that results a loss of production about 15% every year (Azad et al 2020). Soil nematodes are tiny (0.3 -5.0 mm) worm-like animals that are plethoric and numerous in all told soils (Yeates and Bongers 1999).…”