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The aim of the present study was to identify the active principle from Catharanthus roseus leaf using larvicidal bioassay against three mosquito species viz. Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. Preliminary studies of the three successive extracts such as hexane, chloroform, and methanol against Ae. aegypti larvae showed that the chloroform extract was more active with LC50 and LC90 values of 40.09 ppm and 189.15 ppm respectively. Bioassay guided fractionation of the active chloroform extract resulted in the isolation of a triterpenoid (ursolic acid) as the active constituent. Three derivatives acetate, formate, and benzoate were prepared using this, and they were tested for their larvicidal activity against three mosquito species. The acetyl derivative was highly active against all the three species compared to the parent compound ursolic acid; the activities of benzoate and formate were higher than ursolic acid when tested against Cx. quinquefasciatus. This is the first report related to ursolic acid from C. roseus with mosquito larvicidal activity. The pure compound could be considered for medicinal and other pharmacological applications in future.

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The present study was aimed to isolate active constituents from Blumea axillaris (Lam.) DC (Asteraceae) against phytopathogenic fungi. Bioactivity guided fractionation of the successive n-hexane, chloroform and methanol extract led to the isolation of the monoterpene ester (4 R,5S)-4-hydroxy-7-tigloyloxycarvotanacetone (1). The compound 1 was converted into acetyl derivative (2). The acetyl derivative (2) and the parent compound 1 were tested again phytopathogenic fungi by using mycelial inhibition and minimal inhibitory concentration values were found out by the broth microdilution method. The acetyl derivative (2) showed the highest antifungal activity against Rhizoctonia solani and Aspergillus niger. Based upon in vitro results, compound 1 was tested against Fusarium oxyporum (wilting disease) and compound 2 was tested against R. solani (leaf blight disease) in vivo using the foliar spray method. Both compounds had no phytotoxicity and also in silico docking study showed that both compounds were binding similarly as commercial fungicide carbendazim.

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The aim of the present study was to screen for mosquito larvicidal activity of methanol extract of a wild mushroom Psathyrella candolleana against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. Larvae and eggs were exposed to four different concentrations (62.5, 125, 250, and 500 ppm) and mortality was assessed 24 and 120 h after treatment. The LC50 and LC90 values of the extract were calculated. Methanol crude extract of P. candolleana showed good larvicidal activity against the third instar larvae of Cx. quinquefasciatus with LC50 and LC90 values of 166.713 and 259.17 ppm, respectively, after 24 h of exposure. No larvicidal activity was observed against Ae. aegypti and An. stephensi. The methanol extract of P. candolleana presented 88% ovicidal activity against Cx. quinquefasciatus at 500 ppm concentration 120 h after treatment. The active methanol extract was tested for toxicity against non-target organism and found was to have no toxicity. Histopathological studies of the treated larvae revealed serious damages to the midgut cells. The mushroom species was confirmed by 5.8S rRNA sequence and phylogenetic tree was constructed. These results suggest that the methanol extract of P. candolleana could be used in Cx. quinquefasciatus control programs as a new eco-friendly larvicide.

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This study was conducted to determine the mosquitocidal activity of 6 species of higher Basidiomycetes collected from various places in the state of Tamil Nadu, India. The mushrooms were identified using MycoKey MMI software. We used morphological characteristics such as size, color, height, width (of the cap, lamellae, stipe, and fruiting body), spore deposits, and the presence or absence of ring to identify species. Eggs and larvae of Culex quinquefasciatus and Anopheles stephensi were exposed to various concentrations (62.5, 125.0, 250.0, and 500.0 ppm) of extracts from the 6 mushrooms. The extracts were dissolved in dimethyl sulfoxide. Among the 6 mushrooms, the methanol extract of Laetiporus sulphureus showed high toxicity toward mosquitoes at different life stages, with 96% larvicidal activity against A. stephensi and 76% activity against C. quinquefasciatus. After 24 hours, we found half-maximal lethal concentrations of 155.862 ppm for A. stephensi and 227.225 ppm for C. quinquefasciatus, and 90% lethal concentrations of 424.128 ppm for A. stephensi and 1011.663 ppm for C. quinquefasciatus. The extracts also showed strong ovicidal activity against mosquito eggs: 100% activity against A. stephensi and 91% activity against C. quinquefasciatus were observed at an extract concentration of 500 ppm 120 hours after treatment. The methanol extract of L. sulphureus was tested for toxicity against a nontarget organism, but we found none. Histopathological studies of the treated larvae revealed serious damage to cells in the midgut. These results suggest that the methanol extract of L. sulphureus is a good natural source for controlling mosquitoes.

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In agriculture, there is an urgent need for alternate ecofriendly products to control plant diseases. These alternate products must possess preferable characteristics such as new modes of action, cost effectiveness, biodegradability, and target specificity. In the current scenario, studies on macrofungi have been an area of importance for scientists. Macrofungi grow prolifically and are found in many parts of the world. Basidiomycetes (mushrooms) flourish ubiquitously under warm and humid climates. Basidiomycetes are rich sources of natural antibiotics. The secondary metabolites produced by them possess antimicrobial, antitumor, and antioxidant properties. The present review discusses the potential role of Basidiomycetes as anti-phytofungal, anti-phytobacterial, anti-phytoviral, mosquito larvicidal, and nematicidal agents.