Efficacy of Phlogocanthus thyrsiflorus against Oligonychus coffeae and Helopeltis theivora in Tea

Joint Action of Botanicals against Helopeltis theivora Waterhouse and Oligonychus coffeae Nietner

“…Mature leaves of P. thyrsiflorus and C. odorata were collected from their natural habitats of Borbheta and Lichubari areas of Jorhat, Assam (26.746°N, 94.2026°E) during September-October, 2017, shadedried, powdered using an electric grinder and extracted with methanol using Soxhlet apparatus (Make: Labotech) (Borbaruah and Kalita, 2019;2020). The methanolic leaf extracts were later dried in vacuo and the supernatant was dissolved in equal volume of acetone on w/v basis to make 100% stock solution.…”

“…The adults of O. coffeae and H. theivora were collected from the Experimental Garden for Plantation Crops (EGPC), Assam Agricultural University, Jorhat and cultured on detached leaves following the detached leaf technique suggested by Das et al (2012;2017). Twenty one-day-old laboratory cultured O. coffeae adults were placed on a TV1 clone leaf disc of 2.5 cm 2 area and allowed to settle for 24 hr (Borbaruah and Kalita 2019;2020). The leaf discs containing mites were then sprayed with plant extracts at desired concentrations using a hand atomizer (Make: Axiva, Capacity: 50 ml) (Borbaruah and Kalita, 2019;2020) and data on morality were recorded at 6, 12, 24 and 48 hr after treatment (HAT).…”

“…Twenty one-day-old laboratory cultured O. coffeae adults were placed on a TV1 clone leaf disc of 2.5 cm 2 area and allowed to settle for 24 hr (Borbaruah and Kalita 2019;2020). The leaf discs containing mites were then sprayed with plant extracts at desired concentrations using a hand atomizer (Make: Axiva, Capacity: 50 ml) (Borbaruah and Kalita, 2019;2020) and data on morality were recorded at 6, 12, 24 and 48 hr after treatment (HAT).…”

“…To study the bioefficacy of plant extracts against H. theivora, three freshly detached shoots (TV1 clone) with three leaves were collected from EGPC, AAU, wrapped with absorbent cotton and placed in a glass vial (7 x 3.5 cm dia), and the vials were filled with sterilized double distilled water to keep the shoots afresh for a longer period. The glass vials were then caged with hurricane lantern glass chimney covered with muslin cloth to prevent the escape of the insect (Borbaruah and Kalita, 2019;2020). A total of five one-day aged old adults were then released and sprayed with plant extracts at desired concentrations with a hand atomizer.…”

“…Chromolaena odorata (L.) King & Robinson (Asteraceae) and Phlogocanthus thyrsiflorus Nees (Acanthaceae) are the most widely distributed and naturally grown perennial shrub of North Eastern India, which to contain essential oils, antimicrobial flavonoids, alkaloids, fatty acids and phenolic compounds with antioxidant, antiinflammatory, antifungal, antimicrobial and antiradical properties (Lawal et al, 2015). This study focused on the bioefficacy of solvent extracts of P. thyrsiflorus and C. odorata, which revealed a strong acaricidal and insecticidal property, respectively (Borbaruah and Kalita, 2019;2020).…”