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Control failure of pests and selectivity of insecticides to beneficial arthropods are key data for the implementation of Integrated Pest Management (IPM) programs. Therefore, the aim of this study was to assess the control failure likelihood of Plutella xylostella and the physiological selectivity active ingredients to parasitoid Oomyzus sokolowskii (Hymenoptera: Eulophidae) and to predators Polybia scutellaris (Hymenoptera: Vespidae) and Lasiochilus sp. (Hemiptera: Anthocoridae). In bioassays, P. xylostella larvae and O. sokolowskii, P. scutellaris and Lasiochilus sp. adults were used. Concentration-mortality curves of six insecticides for P. xylostella were established. These curves were used to estimate the mortality of P. xylostella at the recommended concentration, in order to check a control failure of insecticides to this pest. Furthermore, the lethal concentration for 90% of populations (LC90) and the half of LC90 were used in bioassays with the natural enemies to determine the selectivity of these insects to insecticides. All tested insecticides showed control failure to P. xylostella, indicated by high LC90 and low estimated mortalities (less than 80%). The cartap insecticide was selective in half of LC90 to Lasiochilus sp. and moderately selective in LC90 and the half of LC90, to Lasiochilus sp. and P. scutellaris, respectively. Deltamethrin was moderately selective in the half of LC90 to predator Lasiochilus sp. Cartap, carbaryl, and deltamethrin reduced the mortality of Lasiochilus sp. in the half LC90. The results also showed that the insecticides methamidophos, carbaryl, parathion methyl and permethrin were not selective to any of the tested natural enemies. The role of insecticides in IPM systems of Brassica crops is discussed based on their control failures to P. xylostella and selectivity to their natural enemies.

In Japan, the American serpentine leafminer, Liriomyza trifolii (Burgess) (Diptera: Agromyzidae), was first observed in 1990, causing serious damage on a wide variety of crops. Liriomyza trifolii continues to infest crops today, despite changes in insecticides used between 1990 and the present. In this study, the insecticide susceptibilities of L. trifolii reared for successive generations over 25 years, from 1991 to 2016, as well as of L. trifolii collected in crop fields in 2015, were investigated. The respective results were compared with those of a study conducted by other researchers in 1991. High insecticide susceptibility in all L. trifolii strains was found for isoxathion, spinetoram, spinosad, emamectin benzoate, lepimectin, cartap, cyromazine, and cyantraniliprole. Insecticides appearing to have caused a decrease in susceptibility were clothianidin, dinotefuran, thiamethoxam, thiocyclam, and pyridalyl. Low insecticide susceptibility for all strains was found for malathion, cypermethrin, permethrin, and milbemectin. These results provide useful insights that will inform the management of insecticide susceptibility in successive generations of insect pests in the field and in the laboratory.

Microwave-assisted catalytic technology is potentially promising in the application of water treatment due to its merits of high reaction rates, simple equipment and operations. In case of the cartap wastewater rarely studied, the easy transformation of cartap into metabolites could induce higher toxicity. This study aimed to develop a novel catalyst Ce/Co/γ-Al2O3 to dispose cartap effectively. The catalyst was prepared by loading Ce and Co on the surface of the support Al2O3, followed by characterization with X-ray diffraction, scanning and transmission electron microscopies. Based on the treatment results, the microwave-induced catalytic oxidation procedure over Ce/Co/γ-Al2O3 could decompose the contaminants efficiently and fast in the case of a low oxidant dosage and a wide pH range. Under the conditions of pH of 5, microwave power of 450 W, catalyst dosage of 0.7 g and hydrogen peroxide dosage of 0.2 mL, the activity of Ce/Co/γ-Al2O3 catalyst could reach up to 86.08%. Importantly, the Ce/Co/γ-Al2O3 catalyst displayed excellent stability after using for 6 times in the degradation process. This work paved a new way for the effective catalyst design for efficient microwave-induced oxidative degradation.

Insecticides are extensively applied in crop production and sometimes at higher concentration than their recommended doses, which has become an environmental hazard. Sustainable agricultural practices highlight minimal application of insecticides at low concentration. Use of controlled release formulations (CRFs) of pesticides in which active compound is associated with inert materials has emerged as an appealing alternative. In this study, nanospheres of insecticide cartap hydrochloride were developed using chitosan (CS) in the presence of tripolyphosphate (TPP) as crosslinker with the help of ionic gelation method, for the delivery of cartap hydrochloride. The nanoformulations were characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) spectra. The FESEM images revealed that the size of chitosan tripolyphosphate (CS-TPP) nanospheres (nps) was in range of 117.01–185.27 nm, whereas cartap hydrochloride entrapped chitosan tripolyphosphate (C-CS-TPP) nanospheres had a size of 163.50–276.74 nm. FTIR results confirmed loading of cartap hydrochloride into chitosan tripolyphosphate nanospheres. The nanospheres showed encapsulation efficiency of 86.1% and were stable for 30 days at ambient temperature. In vitro release kinetics of insecticide from nanospheres followed a non Fickian diffusion mechanism. These nanospheres can act as slow-release formulation for the delivery of insecticide to the target organisms over a period of time, which is effective as well as environmentally safe.

The South American tomato pinworm, Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae), is heavily targeted by insecticide applications. Methoxyfenozide is highly effective against T. absoluta with reduced side effects to natural enemies. This work aimed to (1) genetically and biochemically characterize resistance of the T. absoluta GBN population to methoxyfenozide, (2) establish cross resistance profiles with other insecticide groups and (3) monitor resistance in populations with the goal of improving T. absoluta insecticide resistance management (IRM). Methoxyfenozide resistance was completely recessive, polyfactorial and autosomal. Effective dominance revealed that 10 mg methoxyfenozide/L would be enough to eliminate susceptible homozygotes and heterozygotes, thus used to diagnose resistance in field populations. The synergism of methoxyfenozide toxicity in the resistant population for PBO (SR = 95×), DEF (SR = 51×) and DEM (SR = 45×), suggested monooxygenases, esterases and glutathione S-transferases as resistance mechanisms. However, only monooxygenase activity appeared to be involved in methoxyfenozide resistance. Resistance ratio for methoxyfenozide (2352-fold) after selection and cross-resistance ratios of a lab-selected GBN strain (“GBN-Sel”) were significant relative to a susceptible strain “JDR1-Sus” for tebufenozide (656-fold), cartap hydrochloride (10.68-fold), deltamethrin (4.70-fold), abamectin (2.65-fold), lufenuron (2.22-fold) and indoxacarb (1.92-fold), with negative cross-resistance to spinetoram (0.32-fold). Evidence of control failures was observed in 10 field populations of T. absoluta (mortalities between 13 and 76%), and all populations showed frequencies of resistant phenotypes (percentage survivorship ranging between 4 and 96%). A rational basis for managing resistance to bisacylhydrazines is discussed, along with details of recommended T. absoluta resistance management tactics.

Aim: The aim of the present study was to synthesize a castor oil-based matrix (COBM) for preparing a castor oil-based agro-formulation with cartap hydrochloride for controlling Xanthomonas oryzae, a rice pathogen. Methodology: Physio-chemical analysis of castor oil and constituents of fatty acid methyl esters were carried out by standard methods. Castor oil base matrix, with standardised ratio of oil: alkyl polyglucoside emulsifier (Simulgreen), was first synthesised, then ultrasonicated for size reduction and further tested for its stability. It was also characterised by thermal analysis and by optical microscopy. This base matrix and cartap hydrochloride were used to prepare an agro formulation. The activity of this agro formulation, against Xanthomonas oryzae (GenBank Accession number-VITXO MK547277.1), previously isolated from an agricultural paddy field in Vellore district (12.9165ºN, 79.1325ºE), was studied by well diffusion method using standard protocols. Results: Physio-chemical analysis revealed favourable characteristics for castor oil. Thermal analysis and optical polarised microscopic studies showed the presence of liquid crystals in the formulated base matrix. Its agro-formulation with cartap hydrochloride showed 22 mm zone of inhibition against the isolated Xanthomonas oryzae. However, aqueous solution of cartap hydrochloride showed a 13 mm zone of inhibition only, when tested at a similar concentration (2000 ppm), by well diffusion studies. Interpretation: The liquid crystal containing base matrix facilitated slow and sustained release of cartap hydrochloride from the castor oil-based agro-formulation to achieve good activity against Xanthomonas oryzae. Key words: Agro formulation, Cartap hydrochloride, Castor oil, Oryza sativa, Simulgreen, Xanthomonas oryzae

A field experiment carried out at the College of Agriculture, V C Farm, Mandya, Karnataka evaluated the efficacy of insecticides viz., indoxacarb 15.8EC @ 0.5 ml/l, flubendiamide 48SC @ 0.15 ml/l, chlorantraniliprole 18.5SC @ 0.12 ml/l, benfuracarb 3G @ 33 kg/ha, cartap hydrochloride 4G @ 25 kg/ha, fipronil 0.3G @ 25 kg/ha, acephate 75SP @ 1g/l and chlorpyriphos 20EC @ 2ml/l against major defoliators of rice viz., rice hispa, leaf folder, caseworm and horned caterpillar during kharif, 2018. The reduction of leaf damage over untreated control after imposing treatments was maximum with flubendiamide 48SC (56.99-82.72%) followed by cartap hydrochloride 4 G (52.24- 79.69%). Also, flubendiamide 48SC @0.15 ml/l was the most effective with maximum cost benefit ratio.

Herein, a novel and sensitive fluorescence method for cartap determination is established on the basis of the inner filter effect (IFE) of gold nanoparticles (Au NPs) on the fluorescence of glutathione protected Cu NCs (GSH-Cu NCs). In the presence of Au NPs, the fluorescence of GSH-Cu NCs was strongly quenched by the IFE because the absorption spectra of Au NPs overlap well with the emission spectra of GSH-Cu NCs. Upon addition of cartap, cartap could induce the aggregation of Au NPs whose absorption spectrum does not overlap with the emission spectrum of GSH-Cu NCs. Then, with the increase in cartap concentration, the IFE-decreased fluorescence was gradually recovered, realizing the fluorescence sensing of cartap. Under optimal conditions, the proposed method has a good linear relationship with cartap concentration in the range of 7-100 nM, and the detection limit is 3.34 nM. In addition, satisfactory results were obtained for cartap analysis using tap water and cabbage as real samples, which demonstrated that the method as-developed would have great practical application prospects.

The freshwater fish Cirrhinus mrigala was exposed to Cartap hydrochloride (50% SP) for 24, 48, 72 and 96 h. The LC 50 values were found to be 0.436, 0.419, 0.394 and 0.376 mg-1 in static method and 0.399, 0.371, 0.361 and 0.339 mg.L-1 in continuous flow-through system. The static LC50 values are higher than the continuous flow-through method. The LC50 values showed a decreasing trend with an increase in time of exposure in both the methods. The decrease was more in a continuous flow-through method than in the static method. The fish were exposed to sub-lethal (1/10th of 96 h LC50 value 0.0376 mg.L-1) and lethal (96 h LC50 value 0.376 mg.L-1) concentrations of the pesticide for 24 and 96 hours to study the alterations in glycogen, total proteins and nucleic acids (DNA & RNA) contents of various tissues viz., gill, brain, liver, kidney and muscle. Glycogen, total proteins and nucleic acids (DNA & RNA) content values decreased in all the tissues of exposed fish and the per cent decrease is more apparent in lethal concentrations than in sub-lethal concentrations. From the present study, it can be concluded that Cartap hydrochloride caused a decline in the glycogen, total protein and nucleic acids (DNA, RNA) content in Cirrhinus mrigala and the changes are more pronounced in lethal exposure than in sub-lethal exposure.

Sheath blight is one of the most important diseases of rice worldwide causing serious yield losses. The study was conducted to determine the best and most eco-friendly combination of different IDM practices for the management of the disease under field conditions. Research findings over two crop seasons, suggests that IDM practices (treatment T3) which included seed treatment with carbendazim (2 g/kg) along with one foliar application of carbendazim (@1 g/m2) 7 days before uprooting the seedlings + application of DAP @ 108 g/10 m2 nursery area (to supply 20 kg nitrogen and 50 kg phosphorus per hectare) and MOP @ 85 g/10 m2 nursery area (to supply 50 kg potassium/ha) before sowing + application of 120N:60P:40K:25Zn (100% recommended dose). Additional 25% N was applied at booting to make the plants more prone to the diseases) + one blanket application of granular insecticide (cartap hydrochloride 4% G @ 18.75 kg/ha) at 15 DAT + two foliar sprays of propiconazole @ 0.1% first at booting stage and second after booting stage, if disease appears was proved most effective and consistent in reducing the severity (46.21%) and incidence (39.72%) of sheath blight disease. The treatment also increased the grain yield up to 10.83%. This shows that the IDM practices have significant effect on disease management and also in improving the yield.

Objectives Human exposure to heavy metals and pesticides is a worldwide major health problem. These environmental pollutants have been considered as the most neurotoxic agents and responsible to causing neurological toxicity. Plant-based therapeutic supplement may be used in the event of toxicity. Citrus limon contains several useful bioactive ingredients including flavonoids, dietary fiber, carotenoids, vitamins, pectin, minerals, and essential oils, which are responsible for its therapeutic potential. In the present investigation, we have studied the toxicity of heavy metals such as lead (Pb) and a carbamate pesticide such as cartap (Cp) on rat brain acetylcholinesterase (AChE). Methods The chemical characterization of C. limon involved determination of total antioxidants and 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging activity using known methods. The AChE activity and its kinetic characterization were performed by assaying the enzyme activity at varying substrate concentrations, pH, temperature, and time of reaction. Its different kinetic parameters such as K i , V max, K m , K cat, and K cat/K m were determined by using standard procedures. The amelioration potential of the extract was evaluated on the neurotransmission system of rat brain AChE treated with Pb, Cp, and their combination (Pb–Cp), considering their 50% inhibitory concentration (IC50) values. Results The optimal activity of rat brain AChE was recorded at 25 µg of protein, pH of 7.4, substrate concentration [S] of 0.5 mM, and temperature of 37.4–40°C. The enzyme was stable for 10 min when incubated at 37.4 °C in vitro. The enzyme displayed 70% of its activity remaining even after 160 min of incubation in this condition. It may be stable up to 1 month when stored at −20°C. The IC50 values for Pb, Cp, and Pb–Cp were found to be 75, 2.9, and 5 mM, respectively. Pb, Cp, and Pb–Cp inhibited the activity of rat brain AChE in the noncompetitive, mixed, and uncompetitive manners, respectively, with their respective K i values to be 675, 2.37, and 22.72 mM. Conclusions The results indicated that the Pb and Cp were able to cause significant alterations in the level and properties of AChE. However, the introduction of lemon juice on Pb- and Cp-treated AChE indicated protection of its activity from their adverse effects. The results may be useful in prospective therapeutic applications of lemon juice or as a food supplement to protect mammalian systems from adverse effects of these toxicants.

Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.

Possible causes of brown plant hopper resurgence were determined at the net-house of Entomology Division of Bangladesh Rice Research Institute (BRRI) during 2015. Causes of resurgence in the form of resurgence ratios were higher with acetamiprid, acephate, chlorpyrifos, cypermethrin, deltamethrin, fenvalerate, lambda cyhalothrin, thiamethoxam insecticides compared to imidacloprid, cartap, dinotefuran, isoprocarb /MIPC, phenthoate, pymetrozine when even applied at recommended dose. However, thiamethoxam, imidacloprid, isoprocarb / MIPC and cartap applied at sub-lethal dose produced higher resurgence ratio of BPH than others. Isoprocarb / MIPC, a commonly used recommended insecticide was found to have a higher resurgence ratio with the insecticide treatment at the egg stage (1.71) and combination of all stages (0.82). These insecticides influenced on the growth and reproductive physiology of rice brown planthopper and consequently resurgence ratio ranged increased. SAARC J. Agri., 18(1): 117-128 (2020)

The major production constraint of rice in enhancing productivity is due to attack by pests. Rice stem borer and leaf folder are considered as economic pests and influence the yield if proper timely management practices are not adopted. In case of severe pest incidences the usage of insecticides is inevitable. Among various modes of application of insecticides, seed treatment is mostly advantageous as it is required in small amount and offers control of target pests and ensuing the establishment of healthy and vigorous plants. Hence, studies on efficacy pertaining to Chlorantraniliprole 625g/L FS (lumivia) at different concentrations along with check chemicals viz., cartap hydrochloride 4G and untreated control were evaluate at Agricultural Research Station, Vuyyuru during kharif, 2019 and rabi 2019-2020 to assess the efficacy of various test chemicals against stem borer and leaf folder infesting direct sown rice. The experimental trial was laid out with seven treatments that were replicated four times and treatments were imposed as seed dresser and broadcasted as direct sown rice. The data on per dead hearts and per cent leaf folder damaged leaves at 30, 40, 50, 60 and 70 days after sowing were recorded for both rice variety (MTU 1061) and rice hybrid (28P67). The results revealed that, among various test chemicals the treatment T4 (Chlorantraniliprole 625g/L FS @ 90 g a.i./ha) had registered highest per cent reduction of stem borer with 76.71 & 68.60 in kharif and rabi seasons of study period for rice variety. With respect to rice hybrid the per cent reduction of stem borer incidence over control was 78.19 & 65.09 per cent in kharif and rabi, 2019-2020, respectively. Similarly, the leaf folder damaged leaves were also recorded least in T4 with 61.06 & 62.96 per cent reduction over control with respect to rice variety during kharif and rabi, 2019-2020, respectively, whereas the corresponding values for rice hybrid was 61.04 and 71.64 during kharif and rabi seasons, respectively. Hence, it can be concluded that chlorantraniliprole 625g/L FS @ 90 g a.i./ha@ (lumivia) is effective as seed dresser in suppressing stem borer and leaf folder in direct seeded rice with no phytotoxicity on rice crop and no adverse effects on natural enemies.

Cartap is a thiocarbamate pesticide widely-used to protect rice crops, one of the most mass-produced cereals worldwide. Effluents containing cartap pose serious environment and health risks due to the acute toxicity of this emerging contaminant. This work evaluates the capabilities of the Fenton process to efficiently remove cartap from water matrices. Process parameters such as hydrogen peroxide dosage, ferrous ion concentration and operating pH were optimized using Box-Behnken design. Results showed complete cartap removal with Fenton oxidation in a fluidized-bed reactor while eliminating sludge generation during treatment. Fluidized-bed Fenton process had improved reduction in chemical oxygen demand and total organic carbon due to the contribution of heterogeneous Fenton catalysis to the overall degradation of cartap species compared to conventional Fenton in a batch reactor. Furthermore, competitive reactions and scavenging effects in complex natural water matrices were simulated with the use of inorganic ions such as nitrate, chloride, and phosphate. Results demonstrated the detrimental effect of phosphate ions on Fenton oxidation due to the precipitation of soluble catalysts as iron phosphates, which stops the catalytic Fenton cycle and thus the production of oxidants for contaminant degradation.

Backgroud Pesticides are widely used to control insect infestation and weeds in agriculture. However, concerns about the pesticide residues in agricultural products have been raised in recent years because of public interest in health and food quality and safety. Thus, rapid, convenient, and accurate analytical methods for the detection and quantification of pesticides are urgently required. Results A nanohybrid system composed of gold nanoparticles (AuNPs) and tetrakis(N-methyl-4-pyridiniumyl) porphyrin (TMPyP) was used as an optical probe for the detection and quantification of five pesticides (Paraquat, Dipterex, Dursban, methyl thiophanate and Cartap). The method is based on the aggregation effect of pesticides on the carboxyl group modified by AuNPs. Subsequently, with the help of particle swarm optimization-optimized sample weighted least squares-support vector machine (PSO-OSWLS-SVM), all the pesticides could be successfully quantified. In addition, partial least squares discriminant analysis (PLS-DA) was applied and the five pesticides were satisfactorily recognized based on data array obtained from the ultraviolet visible (UV-visible) spectra of AuNP-TMPyP complex. Furthermore, the quantitative and qualitative analysis of the five pesticides could be also achieved in the complex real samples, in which all the relative standard deviations (RSDs) were less than 0.3‰ and all the linear absolute correlation coefficients were more than 0.9990. Furthermore, recognition rate of the training set and the prediction set based on multiplicative scatter correction (MSC), or second-order derivative (2nd derivative) UV-visible spectra in PLS-DA model could reach 100%. Conclusion This method was successfully applied for the rapid and accurate determination of multicomponent pesticide residues in real food samples. © 2020 Society of Chemical Industry.

Lyonetia clerkella Linn. (Lepidoptera: Lyonetiidae) is one of the most destructive insect pests in many parts of the Kashmir valley. In order to find an effective control agent against this lepidopteran pest, we determined the effectiveness of four synthetic insecticides, viz. Dichlorvas 76EC, Chlorpyriphos 20EC, Dimethoate 30EC, and Cartap hydrochloride 4% GR under both field as well as in laboratory conditions. The distilled water was also used as a control in the experiments. The mortality caused by these insecticides was recorded in both larval as well as in adult bioassay experiments. In the larval bioassay experiment, the highest mortality was caused by Cartap hydrochloride 4% GR (93.13%) followed by Dimethoate 30EC (88.97%), whereas in adult bioassay experiment, the highest mortality was caused by Dimethoate 30EC (94.03%). Results obtained in the present study are promising and may be used as a control strategy for the management of this severe leaf miner pest; however, no recommendations concerning the potential use of insecticides for apple orchards can be given, and further studies are needed in this respect, especially under field conditions.

Yellow stem borer (YSB) is one of the most serious and monophagous pest of paddy in India. Field experiments were carried out to assess the different management modules against the yellow stem borer in paddy during the Kharif season of 2019 and 2020. The results on efficacy of modules revealed that during both the years the minimum ‘Dead Heart’ (DH) (10.1 and 11.4% during the year 2019 and 2020, respectively) was recorded in M3 (clipping of terminal shoots at the time of transplanting and application of cartap hydrochloride 50 SP) followed by M2 (11.9 and 14.5% during the year 2019 and 2020, respectively) in which 1st application was done with fipronil 0.3G and 2nd with NSKE 5% and M1 (19.6 and 20.9% during the year 2019 and 2020, respectively) i.e. farmers’ practice where only carbofuran 3G was applied. ‘White Ear Head’ (WEH) was also recorded minimum in M3 (11.6 and 12.1% in the year 2019 and 2020, respectively) followed by M2 (13.3 and 16.4% in the year 2019 and 2020, respectively) and M1 (20.8 and 22.4% in the year 2019 and 2020, respectively) in paddy. Maximum yield (33.8 and 43.1 q/ha during the year 2019 and 2020, respectively) was also recorded in Module 3 practiced clipping of terminal shoots and spraying with cartap hydrochloride 50 SP with the highest BC(Benefit: Cost) ratio 1.52:1 and 1.94:1 in the year 2019 and 2020, respectively. The overall results of the present study indicating the overall superiority of M3 (clipping of terminal shoots at the time of transplanting and two applications of cartap hydrochloride 50 SP at 40 and 60 DAT) in all the aspects i.e. DH, WEH, yield and BC ratio.

Referring to the structural information of the “hit” compound A from the reported pharmacophore-based virtual screening, a series of novel thienylpyridyl- and thioether/sulfoxide/sulfone-containing acetamide derivatives have been designed and synthesized. The structures of new compounds were confirmed by 1H NMR, 13C NMR and HRMS. The single-crystal structure of A was firstly reported. All the new synthesized compounds were evaluated for insecticidal activities on Mythimna separata Walker and Plutella xylostella L. Through a step-by-step structural optimization, the high insecticidal agents, especially towards Plutella xylostella L., have been found, and thienylpyridyl- and sulfone/thioether-containing acetamides Iq, Io, Ib and A, which are comparable with the control insecticides cartap, triflumuron and chlorantraniliprole in the present study, can be used as novel lead structures for new insecticides innovation research. In addition, some of the compounds, e.g., A, Ih, Id, Io and Iq, also exhibited favourable fungicidal activities against Physalospora piricola, Rhizoctonia cerealis and Sclerotinia sclerotiorum and would provide useful guidance for the design and development of new fungicides.

The present investigation entitled Evaluation of the efficacy of some insecticides against rice yellow stem borer, Scirpophaga incertulas (Walker) was undertaken at MAE Farm, Regional Agriculture Research Station, Karjat (M.S.) during Kharif 2018. The overall mean yellow stem borer infestation (dead heart) varied from 1.23 – 7.50 per cent. The T5 (Flubendiamide 20 WG @ 0.005%) recorded minimum (1.23%) infestation of yellow stem borer and which was significantly superior over all remaining treatments. The next effective treatments were T7 (Chlorantraniliprole 18.5 SC @ 0.006%) and T3 (Emamectin benzoate 5 SG @ 0.0015%) which recorded 1.75 and 1.94 per cent infestation, respectively. The T4 (Thiodicarb 75 WP @ 0.113%) recorded 2.26 per cent infestation and was at par with T1 (Cartap hydrochloride 75 SG @ 0.090%) 2.32 per cent infestation. Other treatments with descending order of effectiveness were T6 (Fipronil 5 SC @ 0.01 5) 2.59 per cent infestation and T2 (Lambda cyhalothrin 5 EC @ 0.003%) 2.84 per cent infestation. The maximum infestation 7.50 per cent dead heart was recorded in T8 (untreated control).

A field experiment was conducted to evaluate the efficacy of certain newer insecticides against serpentine leaf miner, Liriomyza trifolii (Burgess) during summer 2019. Among the different chemicals (Abamectin 1.9 EC, 0.00057%, Triazophos 40 EC, 0.05%, Deltamethrin 2.8 EC, 0.0025%, Emamectin benzoate 5 SC, 0.002%, Imidacloprid 17.8 SL, 0.004%, Cyantraniliprole 10.26 OD, 0.018%, Cartap hydrochloride 50 SP, 0.075%), the diamide insecticide cyantraniliprole registered the lowest number of leaf mines (4.34%) and per cent damage on leaves (13.01%) followed by abamectin and deltamethrin. This establishes the supremacy of diamide insecticides in the effective management of serpentine leaf miner on watermelon.

Effect of certain insecticides in rice ecosystem was studied for their role in resurgence of brown plant hopper (BPH) during kharif and rabi 2016-17. Among fourteen insecticides evaluated, seven insecticides viz., chlorpyriphos, profenophos, deltamethrin, cypermethrin, bifenthrin, lambdacyhalothrin and imidacloprid were observed to significantly increase the incidence of BPH over untreated check after 1st, 2nd and 3rdsprays consistently and resulted in induced resurgence. Acephate, monocrotophos, cartap hydrochloride, fipronil, chlorantraniliprole, buprofezin and pymetrozine effectively controlled the BPH and did not induce resurgence. Thus, these can be used judiciously, with periodic monitoring of resistance and resurgence.

Field experiments were conducted during kharif season 2015-16 at Agriculture Research Station, Gangavathi. Two doses of Flubendiamide 0.7% Gr @ 70 and 85 g a.i./ha, two doses of Spinetoram 0.8% Gr @ 50 and 60 g a.i. ha-1 and standard check Cartap hydrochloride 4% Gr @ 1000 g a.i. ha-1 was tested against yellow stem borer infesting transplanted paddy. Results revealed that, flubendiamide 0.7% Gr at 100 g a.i./ha was found quite effective against YSB recording mean per cent dead heart (DH) and white ear head (WEH) of 1.59 and 1.40 respectively, followed by its next lower dose of 85 g a.i./ha (1.81 DH% and 1.96 WEH %), which was found superior to spinetoram 0.8% Gr @ 60 and 50 g a.i./ha during 2015-16. All the granular insecticides recorded the higher grain yield compared to the untreated check. However maximum yield was recorded in the treatment, flubendiamide 0.7% Gr @ 100g a.i./ha (66.29 qts/ha) and minimum yield was in untreated check plot (48.49qts/ha). Based on the evaluations it can be concluded that, the granular insecticide flubendiamide 0.7% Gr @ 85-100g a.i./ha found superior in reducing the dead heart and white ears and in obtaining higher grain yield Moreover, these new insecticide molecules are comparatively safer to non-targeted organism in comparison with other conventional insecticides.

Bioefficacy of new formulation of carbofuran 3CG were tested in the field condition against stem borer and leaf folder in paddy during kharif 2017 and 2018 at Agricultural Research Station, Gangavathi, and Karnataka. The results confirmed that carbofuran 3CG is an effective chemical in reducing the pest population. Three doses of carbofuran 3CG (750, 1500 and 3000 g.a.i/ha) were tested along with the fipronil 5% SC, carbosulfon 25% EC and cartap hydrochloride 4G. among the treatments carbofuran 3CG @ 3000 g.a.i./ha effectively reduced stem borer (2.25 and 2.41% of white ears) and leaf folder infestation (0.34 and 0.37 larvae/hill) and increased grain yield during both the years as compared to untreated check.

The entomopathogenic fungus Metarhizium majus (isolate no. CPCRIMKY-1) is a potential bio control agent against the major pest of banana, Odoiporus longicollis (Olivier). Banana is highly vulnerable to a plethora of pests and diseases which are managed by the application of pesticides. Hence, it is imperative that the reactions of these pesticides when used in banana agro-system with M. majus, is studied in detail. A study was conducted at the College of Agriculture, Kerala Agricultural University, India to evaluate the effect of pesticides used on banana at field doses, on the survival of the entomopathogenic fungus. This study is expected to help in formulating meaningful biotic stress management strategies in banana agro-systems, especially in areas of severe Odoiporus longicollis infestation. It was found that thiamethoxam at 0.01 and 0.03% and cartap hydrochloride 0.05% were safe while all tested fungicides except azoxystrobin 0.1% were toxic to M. majus. Wherever there arises a demand for the application of fungicides in banana, application of M. majus may be adopted after following a proper waiting period. Synergistic effect of thiamethoxam and M. majus can be used for the effective management of O. longicollis.