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The present study reports, bioefficacy evaluation of effective compounds against Meloidogyne incognita and Sclerotium rolfsii in pot cultured tomato. The identified five most effective compounds, i.e. (2 E )-1-(4-Methylphenyl)-3-ferrocenyl-prop-2-en-1-one ( 6g ), (2 E )-1-(4-Methoxyphenyl)-3-ferrocenyl-prop-2-en-1-one ( 6h ), (2 E )-1-(3-Bromophenyl)-3-ferrocenyl-prop-2-en-1-one ( 6j ), (2 E )-1-(2,4-Dichlorophenyl)-3-ferrocenyl-prop-2-en-1-one ( 6k ) and (2 E )-1-(3,5-Dichloro-2-hydroxyphenyl)-3-ferrocenyl-prop-2-en-1-one ( 6p ) along with Carbofuran 3G as positive control were tested at 20, 40 and 80 ppm by soil drenching and root dipping methods. The study revealed that all plant growth parameters were positively influenced by these compounds. The presence of an electron releasing group positively influenced the efficacy, and the activity was highest in compounds 6g and 6h at 80 ppm. Based on in vitro results against S. rolfsii , (2 E )-1-Ferrocenyl-3-(4-bromophenyl)-prop-2-en-1-one ( 3b ), (2 E )-1-Ferrocenyl-3-(2,6-dichlorophenyl)-prop-2-en-1-one ( 3o ) and (2 E )-1-(5-Chloro-2-hydroxyphenyl)-3-ferrocenyl-prop-2-en-1-one ( 6o ) along with Tebuconazole 25.9% EC and Hexaconazole 5% SC as positive control were evaluated. The shoot length was found to be highest (24.50 cm) in plants treated with 3b followed by 3o and 6o at 1000 ppm. The percent disease incidence was significantly decreased as compared to control. The percent disease incidence was found to be minimum in plants treated with 3b at 1000 ppm. However, root dipping was not as effective as soil drenching. Therefore, ferrocenyl chalcone derivatives proved to be of great fungicidal and nematicidal potential opening new opportunities for expanding their effectiveness as new pest control agents.

A series of ferrocenyl chalcones using acetylferrocene, with ferrocenyl group at the keto carbonyl group, and different aldehydes were synthesized and their bioefficacy evaluation was done against Sclerotium rolfsii , Alternaria solani and Meloidogyne incognita. In continuation of our quest for potent crop protection products, in the present study, a series of 18 substituted ferrocenyl chalcones were synthesized in which ferrocenyl group was attached to the aldehyde moiety, using ferrocenecarboxyaldehyde and different acetophenones by microwave method (MM) and conventional method (CM) [ cf : MM 1 to 5 min; CM 12-40 h] and characterized by various techniques viz. IR, LC-HRMS, 1 H-NMR and 13 C-NMR. In vitro fungicidal activity showed that compound, (2 E )-1-(5-Chloro-2-hydroxyphenyl)-3-ferrocenyl-prop-2-en-1-one ( 34) (ED 50 = 21.50 mg L -1 ) was found to be most active against S. rolfsii and compound, (2 E )-1-(4-Bromophenyl)-3-ferrocenyl-prop-2-en-1-one ( 21) (ED 50 = 31.14 mg L -1 ) showed highest activity against A. solani. As regards nematicidal activity, compound (2 E )-1-(3-Bromophenyl)-3-ferrocenyl-prop-2-en-1-one ( 29) was more potent with LC 50 values of 11.95, 8.07 and 4.34 mg L -1 at 24, 48 and 72 h, respectively. QSAR study revealed that MLR for S. rolfsii ( r 2 = 0.9834, q 2 = 0.8975) and A. solani ( r 2 = 0.9807, q 2 = 0.8713) and PLS for M. incognita ( r 2 = 0.9023, q 2 = 0.7818) were the best models.

Controlled release (CR) nanoformulations of Mancozeb (Manganese-zinc double salt of N, N -bisdithiocarbamic acid), a protective fungicide, have been developed using poly (ethylene glycols) (PEGs) based functionalized amphiphilic copolymers and evaluated for the management of early blight in tomato. During the field experiment, it was observed that number of infected leaflets/plants were less in developed formulation treated plants as compared to commercial products. Number of infected leaflets per plant was 2.40-4.60 and the number of fruits per plant were 6.40-9.00 at 50 mg L -1 , whereas at 100 mg L -1 , the corresponding numbers were 2.10-4.10 and 6.30-9.10 respectively. These formulations can be used to optimize the release of Mancozeb to achieve disease control for the desired period depending upon the matrix of the polymer used. Importantly, sufficient amount of active ingredient remains available for a reasonable period of time after application leading to reduced number of applications of pesticide.

A series of 42 phenolic acid amides, synthesized using different phenolic acids (salicylic acid, 3-hydroxy cinnamic acid, p-coumaric acid, caffeic acid, ferulic acid, o-coumaric acid, cinnamic acid and amines (propyl amine, hexyl amine, heptyl amine, undecyl amine, hexadecyl amine, octadecyl amine) were screened for their insecticidal activities against Brown Planthopper (BPH), Nilaparvata lugens . These phenolic acid amides showed moderate to good insecticidal activity with the lowest LC 50 value of 63.84 ppm from N-propyl-2-hydroxycinnamamide. 2D-Quantitative structural activity relationship (2D-QSAR) analysis of these phenolic acid amides was carried out by developing three different models namely multiple linear regression (MLR), principal component regression (PCR) and partial least squares (PLS). Statistical significance and predictive ability of these models were assessed by internal and external validation and verified by leave one-out cross-validation. PLS (model 3) was found best for QSAR study with correlation coefficient ( r 2 ) 0.8388, cross-validated correlation coefficient ( q 2 ) 0.7797 and r 2 pred 0.7347. It was found that + vePotentialSurfaceArea, XAMostHydrophobic, SaasCE-index, T_O_O_3 and T_O_O_6 are the major descriptors which influence the insecticidal activities of these phenolic acid amides. The QSAR study could help in structural optimization of phenolic acid amides in developing potential compounds to get better bioefficacy against N. lugens .

A new series of halogenated Schiff bases was synthesized by the condensation of 5-fluoro-2-hydroxy acetophenone and 3,5-dichloro-2-hydroxy acetophenone with different alkyl amines, namely propyl, pentyl, hexyl, heptyl, octyl, nonyl, dodecyl, tetradecyl, hexadecyl, and octadecyl amines, under microwave irradiation. Newly formed molecules were characterized by Infrared and nuclear magnetic resonance ((1)H NMR and (13)C NMR) spectroscopic techniques. Further, the Schiff bases were screened for antifungal bioassay, and the results showed potential fungicidal activity against two very important plant infecting fungi, viz. Rhizoctonia solani and Sclerotium rolfsii. Among the screened compounds, 2,4-dichloro-2-[1-(propylimino)ethyl]phenol was found to be the most active compound against both R. solani (ED50 8.02 mg L(-1)) and S. rolfsii (ED50 21.51 mg L(-1)) followed by 2,4-dichloro-2-[1-(pentylimino) ethyl]phenol (ED50 13.02 and 29.57 mg L(-1), respectively). The synthesized compounds were also screened for antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging technique. All the compounds showed very low to moderate activity as compared with Gallic acid.