ABSTRACT
Abstract This study was aimed to explore the chemical composition and biological activities of essential oil from aerial part of Mosla dianthera along with its major isolated compound, carvone. The hydro-distilled essential oil was analysed by GC-MS and biological activities were investigated in terms of antioxidant, anti-inflammatory, herbicidal, antibacterial, anti-fungal and anti-feedant properties. GC-MS analysis led to the identification of forty-nine components contributing 96.2% of essential oil with carvone (41.9%) as the most abundant constituent. The oil and carvone showed good to moderate antioxidant potentials determined by radical scavenging, reducing power and metal chelating activities. Carvone showed good anti-inflammatory activity (78.0%) compared to essential oil (74.2%). Both essential oil and carvone exhibited excellent herbicidal activity against Raphanus raphanistrum subsp. sativus seeds. The essential oil and carvone showed significant anti-bacterial efficacy against Bacillus cereus and Escherichia coli. It was observed that essential oil showed strong antifungal property than carvone against Alternaria alternata and Curvularia lunata. Both the samples exhibited anti-feedant activity in a dose dependent manner against third instar larvae of Spilosoma obliqua. Results obtained revealed the possible applications of essential oil and carvone as a bioactive source of natural antioxidants, excellent herbicide and an effective substance for antifungal and antifeedant activities.
ABSTRACT
Abstract: Bemisia tabaci (Asia II 5) and Trialeurodes vaporariorum are the two devastating species of whiteflies infesting a wide range of vegetable crops in the North-Western Himalayan region. Therefore, the present investigation deals with a comparative study of the morphology and developmental biology of these two whitefly species. The total developmental period from egg to adult was 22.82 and 23.40 days for B. tabaci (Asia II 5) and T. vaporariorum, respectively, which did not differ significantly. The adult longevity, fecundity, and adult emergence in T. vaporariorum is quite higher than B. tabaci (Asia II 5) which were observed as 10.40 days, 118.00 eggs/female, 90.69 per cent and 6.80 days, 73.33 eggs/female, 86.59 per cent, respectively. Similarly, the egg hatching and the survival rate is higher in T. vaporariorum than in B. tabaci (Asia II 5) (95.11, 81.44 per cent and 91.68, 78.09 per cent). Morphological characters such as marginal setae, abdominal setae, vasiform orifice, lingula, and antennae, which were reliable characters for the identification of both whitefly species and diagnostics of the two whiteflies, were explicated in a comparative discussion.