Volume 21, Issue 3 (5-2019)
Abstract
The study investigated the toxicity of Parthenium extracts in comparison with Neem extracts against 3rd and 4th instar larvae of the diamondback moth, Plutella xylostella L.. The side effect of Parthenium extracts was also examined against larval parasitoid, Cotesia plutellae. Extracts obtained from their respective plants were dissolved independently to get stock solutions, which were further diluted to different concentrations (1%, 2%, and 3%) with distilled water. The experiment was laid out in completely randomized design with four treatments, including the control, and replicated six times in vitro. Results showed that Parthenium crude extracts was very effective in comparison with the control against P. xylostella, whilst the highest mortality was recorded at 3% concentration of Neem in comparison with Parthenium extracts against both stages of P. xylostella. Overall, the highest mortality was recorded at 3% concentration of Neem extracts followed by 2% Neem extracts, 3% Parthenium extracts, 1% neem, 2% and 1% Parthenium extracts. The lowest mortality was noted in the control (i.e. 70%, 58.33%, 51.67%, 35%, 33.33%, 18.33% and 16.67% in case of 3rd instar mortality whilst 61.67%, 50%, 41.67%, 30%, 16.67% and 15% in case of 4th instar mortality, respectively). Less harmful effect was observed for larval parasitoid, C. plutellae. Finally, it was concluded that all the treatments had the ability to control P. xylostella to some extent, but Parthenium crude extract was less efficient in comparison with Neem extract, as 3% crude extract of Neem had a sufficiently toxic effect on the P. xylostella.
Volume 22, Issue 4 (6-2020)
Abstract
The root-knot nematode, Meloidogyne incognita, is parasitic to the plants and greatly damages the root of many vegetables. The current in-Planta study was designed to explore the nematicidal properties of several botanicals (neem oil, garlic oil, castor oil, extracts of Tagetes patula and Datura inoxia at a standard dose of 2.0%) at District Peshawar, Pakistan. Tomato (cv. Riogrande) was grown in earthen pots for the growing seasons of 2014 to 2016. Pure culture of the root-knot nematodes were grown in laboratory and were applied at the rate of 50 infective juvenile and 200 eggs per root system through soil drench method. Neem oil and Datura inoxia gave the best results by having lower number (2.8 and 5.8, respectively) of galls. Adult females and egg masses were also reduced to 0.9 and 4.8, respectively, per root system. All the treatments differences were statistically significant (P≤ 0.05). Plant growth parameters were also upraised with application of medicinal herbs. This study highlights the nematicidal properties of botanicals for the safe and cheap management of the prevalent root knot nematode. Hence, it is recommended to the farmers for the use of these naturally occurring organic nematicides instead of commercial petro-chemicals that have ill effect on our environment.