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Spodoptera litura Fabricius (Lepidoptera: Noctuidae) is a deleterious agricultural pest worldwide. Field populations of S. litura manifest resistance to almost all conventional insecticides and it is imperative looking for novel biorational insecticides to control this pest. In this regard, this study bioassayed some promising biorational insecticides including botanical, microbial and non-conventional synthetic insecticidal formulations against 3rd instar larvae of S. litura. Bioassay with botanical formulations showed a significant toxicity of oil and extract formulations of neem (Azadirachta indica) causing 70-77% larval mortality in 72 h observation and exhibiting minimum medial lethal concentration (LC50) and time (LT50) values (i.e. 12.32 and 38.01 ppm and 16.67 and 11.68 days, respectively). Among microbial formulations tested, S. litura-nuclear polyhedrosis virus (NPV) and Bacillus thuringiensis kurstaki appeared as the most effective microbial treatments exhibiting minimum LC50 (3.78 × 10³ OB mL-1 and 1.22 × 107 spores mL-1, respectively) and LT50 (3.83 and 3.71 days, respectively) values. While flubendiamide, chlorantraniliprole and spinetoram exerted most significant lethal and sublethal effects on S. litura with minimum LT50 values (i.e. 19.58, 30.78 and 26.25 h, respectively). Larval development time was significantly prolonged by both half and one-fourth doses of flubendiamide and chlorantraniliprole (19.51 and 19.63 days and 17.77 and 17.20 days, respectively), while pupal duration prolonged for spinetoram and lufenuron. Similarly, significant suppression of adult lifespan was exhibited by flubendiamide (11.83 and 11.85 days) and chlorfenapyr (12.28 and 12.06 days). Overall study results advocate further consideration of these aforesaid biorational insecticides against S. litura infestations. However, assessment of their compatibility with each other and with other IPM strategies both under lab and field conditions constitutes future perspectives of this work. [ABSTRACT FROM AUTHOR]

Meloidogyne incognita (Kofoid and White) Chitwood (MI) is a potential threat to tomato (Solanum lycopersicum L.) production. In this study, the inhibitory effect of Moringa oleifera L. (MO) extracts and Steinernema kraussei Steiner (SK) as stand-alone treatments and in combination was assessed to suppress the reproduction and development of MI. Highly susceptible variety of tomato cv. 'Money Maker' was tested for the invasion and development of MI. Aqueous and ethanolic MO extracts were tested in combination with SK at three different concentrations and time intervals. After 12-h 'S' concentration of aqueous MO extract + ethanolic MO extract + SK produced 100% juvenile mortality while the treatment MO + SK caused the least juvenile mortality of MI. Juvenile mortality was increased in a time-dependent manner. Aqueous MO extract + ethanolic MO extract + SK produced 100% egg hatching inhibition at standard 'S' concentration. Plant growth was significantly enhanced in plants treated with MO extracts, SK and their combinations compared to MI treated control plants. The total number of infective juveniles/g root and soil, galls, egg masses, females were highest in MI treated plants while lowest in plants treated with a combination of MI + SK + aqueous MO + ethanolic MO after 60 days of inoculation. SK and MO has demonstrated significant potential to suppress MI infection. Therefore, further investigations should focus on their efficacy at field level to prevent the infection of MI. [ABSTRACT FROM AUTHOR]

The cadusafos (Rugby ®) showed strong nematicidal property in lab experiment and greenhouse trail. Cadusafos 1%, 0.5% and 0.25% was tested in egg hatching, juveniles mortality and invasion and development of root knot nematodes Melodigyne incognita (Kofoid and White) Chitwood in tomato to (Solanum lycopersicum L.). Cadusafos 1% was found to be effective in egg inhibition of Meloidogyne incognita. Cadusafos (Rugby ®) 1% showed 100% while 0.5% and 0.25% showed 72% and 57.3% mortality of juveniles, respectively. Mortality of juveniles increased with increased exposure time and concentration. Invasion, development and reproduction of root knot nematode were evaluated on tomato crop. Data was recorded after 7, 17 and 35 days to observe the penetration and development stages including vermiform, swollen, sausage stage, immature females, adult females and egg masses of M incognita. Maximum reduction of M. incognita was observed when soil was treated with Cadusafos (Rugby ®) 1%. Most effective concentration of cadusafos determined by above experiments was used to assess its effect as protective and curative. Root knot nematode population was reduced when cadusafos was applied as protective application. [ABSTRACT FROM AUTHOR]