Plants dispense localised and systemic defense responses against biotic colonisers and plant resistance to pathogens depends upon timely recognition of pathogen infection and subsequent rapid activation of defense responses through signal transduction pathways. Induction of host defense responses involving compatible and incompatible interactions in tomato landrace, LE996, LE150 and LE1165 (Solanum lycopersicum), and wild relatives, Seijima Jeisei and I979 (S. hirsutum) genotypes, and early blight (EB) pathogen, Alternaria solani were studied. Accumulation patterns of different defense related proteins in resistant genotypes (LE996, Seijima jeisei and I979) and susceptible genotypes (LE150 and LE1165) are reported here. Challenge inoculation led to similar protein profiles in resistant genotypes yielding 11 proteins, unique are 14, 54, and 58 kD proteins that are absent with susceptible genotypes. Resistant genotypes accumulated more proteins well in advance, 6-h after challenge inoculation. Resistant genotype LE996 expressed 54%, 90%, and 52% enhanced enzymatic activity of peroxidase, polyphenol oxidase and phenylalanine ammonia lyase respectively than susceptible LE150 and correlated phenolics accumulation peaked 2-d after challenge inoculation. Activity gel assay indicated the unique expression of PO1 and PO2 in LE996 upon challenge inoculation. Significant increase in expression of chitinases (63%) and b-1,3-glucanase (71%) upon challenge inoculation than susceptible LE150 control was recorded. Western blotting indicated the unique presence of less than 30 kD chitinase in resistant LE996 and Seijima Jeisei and was absent in susceptible LE150. The results demonstrate the importance of pathogenesis-related (PR) proteins in EB resistance and their use as biochemical markers for genotype selection.

Vector control is a serious concern in developing countries. Over the past two decades, phytochemicals have received progressively more attention as insecticide alternatives, and they have recently become the focus in the concept of integrated vector control. α‐Amyrin acetate, the n‐hexane fraction of acetone extract from the leaves of Catharanthus roseus, was evaluated for its larvicidal, pupicidal and fecundity effects as well as insect growth regulator activity against the malaria vector Anopheles stephensi Liston. The highest concentration of 1 p.p.m. produced 100% mortality in first to second instars and 94% mortality in third and fourth instars. In addition, the duration of larval instars and the total developmental time were prolonged, while female longevity and fecundity were markedly decreased. The suppression of pupation and adult emergence was probably due to its action similar to juvenile hormone analogs in combination with growth regulator activity and toxicity, which reduced the overall performance of the malaria vector An. stephensi.

An invasive pest, fall armyworm, Spodoptera frugiperda (J.E.Smith) (Lepidoptera: Noctuidae) attacks maize at every stage of development, from seedling emergence up to cob formation. Early instar larvae were seen mostly on leaves of maize with characteristics pin or shot hole symptoms. Later instar larvae were confined to deep whorls, leaving typically ragged like appearance and fed on the reproductive stage of the crop especially tassels and developing cobs resulting in quality and quantity loss of maize produce. The effect of commercially available Bacillus thuringiensis subsp. kurstaki product, Dipel® against the second instar larvae of Fall Armyworm (FAW )was not promising under laboratory conditions. Hence, an effort was made to add an adjuvant along with B. thuringiensis to increase the virulence of commercially available B. thuringiensis.The Laboratory bioassays with B. thuringiensis and seven chemical additives ( T1- Bt + Boric acid, T2- Bt + Zinc oxide, T3- Bt + Sodium nitrate, T4- Bt + Peptone, T5- Bt + Urea, T6- Bt + EDTA, T7- Bt + Citric acid & T8-  Bt alone T9- Control) were tested against second instar larvae of Spodoptera frugiperda larvae. The results showed that B. thuringiensis plus sodium nitrate (T3) promoted maximum mortality 82.2 per cent with a minimum LC50 value of 54.620 mg/l. Sodium nitrate boosted B. thuringiensis activity at a concentration of 0.05 per cent by 2.128-fold than B. thuringiensis alone. Overall, sodium nitrate improved the efficacy of B. thuringiensis spray at the maximum level followed by boric acid, urea, EDTA and peptone.

Okra is an important vegetable, and it is subject to heavy yield losses by insect pests, of which the shoot and fruit borer Earias spp. is serious. Insecticides are used against this pest, leading to insecticide residues. This study evaluates Milkoid, an LAB formulation spray in field by spraying in tandem with flubendiamide and bleaching powder (calcium hypochlorite). The results indicate that the population of epiphytic LAB density was maximum on plants sprayed with Milkoid with or without flubendiamide. The pest damage was significantly reduced after spraying flubendiamide with or without bleaching powder (3.76- 5.30%). Milkoid accelerated the degradation of flubendiamide with the dissipation rate of 70.07% on 15th day after spray. The efficacy of Milkoid in reducing the toxicity and the potential of calcium hypochlorite as an antimicrobial agent and the shoot and fruit borer management are discussed.