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Bacterial microbe-associated molecular patterns (MAMPs) play an important role in innate plant immunity. This in vitro study evaluated the putative role of protein elicitor PeBA1 derived from Bacillus amyloliquefaciens NC6 strain in eliciting induced resistance type responses in common bean (Phaseolus vulgaris) plants against green peach aphid Myzus persicae. Nymphal developmental time of aphids was significantly prolonged and the fecundity was significantly reduced by different concentrations of PeBA1 elicitor (i.e. 40.51, 24.91 and 16.38 µg mL-1) applied at three different temperature regimes (i.e. 21, 27 and 30 °C). Moreover, foliar application of PeBA1 elicitor protein strongly up-regulated the expression levels of salicylic acid (SA) pathway-associated genes, while the expression levels of jasmonic acid (JA) pathway-associated genes exhibited a moderate induction. Quantification by LC/MSMS revealed a linear increase of both SA and JA plant defense hormones along with the time of exposure. Our findings suggest that the bacterial elicitor protein PeBA1 could be used as an effective biological pest management tool against phloem-feeding insect pests such as green peach aphids M. persicae.

Installation of traps in the agricultural field is an economically important and cheaper technique to observe arthropods diversity. Cost-effective ecological monitoring of arthropods by traps has been gaining interest in the field of environmental entomology since last few decades. This study explains the effectiveness of four different types of traps (pitfall, yellow-sticky, pan and barrier traps) to monitor the arthropod diversity in summer and winter seasons. These traps were installed in different mango orchards located in Punjab, Pakistan. diversity of captured arthropods was 1.5 times higher in summer than in winter season. However, among the traps, pitfall traps were most effective than others for trapping edaphic arthropods in both seasons. The pan traps were found most effective in the summer season, while sticky traps in the winter season. The pitfall traps exhibited highest taxa richness index values (8.00 for summer and 5.00 for winter season), while the lowest values were recorded for barrier traps (5.00 for summer and 3.00 for winter season). Moreover, the pitfall were the most effective traps for the capture or collection of Arachnida, Coleoptera, Hymenoptera, Lepidoptera, Orthoptera and other arthropods. The PVC barrier and sticky traps were found most effective for Dipteran and Hemipteran's insects, respectively, and hence, are recommended for the ecological monitoring of these arthropod groups in future studies.

Whiteflies, Bemisia tabaci Gennadius (Aleyrodidae: Hemiptera), are a polyphagous economically destructive pest of several solanaceous crops around the world. Many secondary metabolites are synthesized by different biotrophic and necrotrophic fungi which are capable of inducing systemic resistance in plants against various phytophagous pests. The present laboratory work demonstrated the anti-insect impact of a protein extracted and purified partially from an entomopathogenic fungus (EPF) Lecanicillium lecanii (Zimmermann) against B. tabaci. Three different concentrations (i.e., 7.43, 11.15, and 22.31 μg mL−1) of this protein were bioassayed to assess its effect on the fecundity rate of B. tabaci on cotton (Gossypium hirsutum L.) plants. Furthermore, the possible implication of this fungal protein in defense pathways of cotton plants was evaluated by determining the expression profiles of salicylic acid (SA) and jasmonic acid (JA) pathways related to major genes through reverse transcription qPCR (RT-qPCR). According to the results, all protein concentrations exerted a significant (F3, 252 = 62.51, p ≤ 0.001) and negative impact on the fecundity rate of B. tabaci females. At the highest protein concentration (22.31 μg mL−1), the minimum rate of fecundity (i.e., 2.46 eggs female−1day−1) of B. tabaci was noted on the seventh day, whereas fecundity rates for the other two protein concentrations (i.e., 11.15 and 7.43 μg mL−1) were, respectively, 3.06 and 3.90 eggs day−1 female−1. The maximum rate of fecundity (6.01 eggs female−1day−1) was recorded in untreated (control) treatments. In addition, the foliar application of L. lecanii derived protein significantly upregulated all SA linked genes (OPR3, PPO1 and COI1) and slightly triggered up the JA linked genes (LOX1, UBQ7 and AOS) in the cotton plants. These findings revealed that this L. lecanii extracted partially purified protein triggered systemic resistance against B. tabaci in the cotton plants, proposing its putative effectiveness as an innovative biological control technique against B. tabaci and other phloem-feeding hemipteran pests. Nevertheless, further investigations such as purification and molecular and functional characterization of this L. lecanii-derived partially purified protein are required.

Global climate warming has been exerting impacts on agricultural pests. Pests also take some strategies to adapt to climate change. Understanding such adaptation could benefit more accurate predictions and integrated management of pest. However, adaptation to climate change has not been widely investigated in agricultural pests but has been well documented in model species, Drosophila, and reviewed by Hoffmann before 2003. To provide recent progress and references for agricultural entomologists who interested in thermal biology, here we have reviewed literatures since 2003 about adaptation to temperature changes under climate change. We mainly summarized thermal adaptation of Drosophila (especially to high temperatures) from three aspects, behaviors, plastic responses and micro-evolution and discussed how Drosophila increases their heat tolerance through these three mechanisms. Finally, we summarized the measures of thermotolerance and concluded the main progress in recent decade about the behavioral thermoregulation, mortality risks driven by limited evolutionary and plastic response under climate change, geographic distribution based on basal rather than plastic thermotolerance. We propose future work focus on better understanding adaptation of organisms including agricultural pests to climate change.

Diaphorina citri Kuwayama (Psyllidae: Hemiptera) and Aphis gossypii Glover (Aphididae; Hemiptera) are destructive sap-feeding pests of citrus and cotton, respectively. This study assessed the toxicity potential of indigenous flora of Soon valley and surrounding salt range (Punjab, Pakistan) against D. citri and A. gossypii. Among acetone extracts of 40 plant species, the extracts of Mentha longifolia (L.) Huds., Melilotus officinalis (L.) Pall., Nerium indicum Mill., Datura alba L. and Salvia officinalis L. showed highest psyllid mortality (i.e. 93, 91, 89, 88 and 81%, respectively). Bioassay with most effective extracts further revealed that the most toxic extracts were S. officinalis, N. indicum and M. longifolia with LC50 values of 18.59, 20.27 and 20.73%, respectively. Similar trend of toxicity was observed in case of their LT50 values. These results suggest the putative effectiveness and further biochemical characterization of these plant extracts for the management of D. citri and A. gossypii and other sap-feeding insect pests.

Plants rely on various physiological and molecular defense mechanisms against biotic stresses such as herbivore insects. Many entomopathogenic fungi synthesize protein molecules that can trigger these plant defenses. This laboratory study characterized the bioactivity of a partially purified protein derived from Beauveria bassiana (ARSEF 2860) against whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), which is an economically important pest of agricultural and horticultural crops worldwide. Different concentrations (i.e., 0.021, 0.042 and 0.063 &mu, M) of fungal protein were bioassayed to determine their sub-lethal effect on the survival percentage and fecundity rate of B. tabaci on tomato (Lycopersicon esculentum) plants. In addition, the putative role of this partially purified B. bassiana protein in the defense mechanisms of plant was assessed through the expression analyses of important genes related to salicylic acid (SA)&mdash, and jasmonic acid (JA)&mdash, associated pathways using RT-qPCR. Results revealed a significant suppression of the survival percentage and fecundity rate of B. tabaci by the fungal protein. Lowest survival (41%) was recorded for the highest concentration of protein (0.063 &mu, M), whereas mean survival for the other two protein concentrations (0.042 and 0.021 &mu, M) were 62 and 71%, respectively. Likewise, the highest and lowest mean fecundity rates were observed for the control and the highest protein concentration (i.e., 3.3 and 1.8 eggs day&minus, 1 female&minus, 1, respectively). Furthermore, the exogenous application of B. bassiana-derived protein on tomato plants strongly up-regulated the SA-related genes (PAL, PR1, BGL2 and EDS1) and slightly up-regulated the JA-related genes (AOC, AOS, OPR3 and LOX) as compared to the control plants. These findings demonstrate the putative role of this partially purified B. bassiana protein fraction in inducing systemic resistance in the tomato plants against B. tabaci, suggesting its further purification and characterization to be used as novel biological pest control tool against B. tabaci and other sap-sucking insect pests.

This study reports the characterization of protein elicitor PeBb1 derived from entomopathogenic fungus Beauveria bassiana ARSEF-2860 strain and its putative role in induced systemic resistance in Brassica rapa ssp. pekinensis against green peach aphid Myzus persicae. The sequence of purified elicitor protein was matched with the genomic sequence of a hypothetical protein BBA_10269 from B. bassiana ARSEF-2860 (GenBank Accession No. XP_008603588.1). The protein-encoding gene PeBb1 contained 534 bp cDNA encoding a polypeptide of 177 amino acids with a molecular mass of 19 kDa. The recombinant elicitor protein was expressed in Escherichia coli using pET-28a (+) expression vector and induced necrosis in the leaves of tobacco. The effects of elicitor protein on aphid M. persicae was determined by applying three different concentrations of PeBb1 (i.e., 26, 35, 53 &mu, M) on B. rapa plants at 4-leaf stage and the treated plants were exposed to newly emerged (0&ndash, 6 h old) apterous adult aphids. Bioassay results showed significant (p &lt, 0.05) sub-lethal effects of the exogenous application of PeBb1 elicitor on M. persicae. Moreover, the RT-qPCR gene expression analyses showed a significant up-regulation of most of the key genes linked to ethylene (ET)- and jasmonic acid (JA)-associated plant defense pathways in elicitor-treated plants. These results not only recommend the putative utilization of PeBb1 elicitor protein in future biological pest control strategies against phloem-feeding insect pests such as M. persicae, but also help in better comprehension of the mechanisms through which beneficial fungi trigger the induced plant resistance.

Many biotrophic and necrotrophic fungi synthesize proteins that may elicit induced plant resistance against different herbivore pests. This in-vitro study elucidates the sub-lethal effect of a partially-purified protein derived from the entomopathogenic fungus Lecanicillium lecanii (Zimmerman) (Hypocreales: Clavicipitaceae) against green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae), an economically important pest of many solanaceous crops including tomato. Bioassays were conducted to determine the impact of different concentrations of protein (i.e. 0.018, 0.036 and 0.054 µM) on the survival and fecundity of M. persicae on tomato (Lycopersicon esculentum) plants. Moreover, the potential role of this exogenous protein in the plant defense mechanism was assessed by expression analyses of key genes associated with salicylic acid (SA) and jasmonic acid (JA) pathways using RT-qPCR. The results indicated a significant negative effect of all protein concentrations on the survivorship and fecundity of M. persicae. The highest concentration (0.054 µM) resulted in lowest survival (46%) of aphids at 7th day post-treatment, while two other concentrations (0.036 and 0.018 µM) resulted in 61 and 71% survival rate, respectively. Similarly, lowest and highest mean fecundity rates were recorded for the highest protein concentration and the control (1.5 and 2.4 nymphs day−1 female−1), respectively. Moreover, L. lecanii-derived protein strongly upregulated the SA associated genes PR1, BGL2 and PAL, and moderately upregulated the JA associated genes LOX, AOS and AOC in protein-treated tomato plants compared to the control plants. These findings demonstrate the systemic resistance induced in tomato plants against M. persicae by the exogenous application of partially-purified protein extracted from L. lecanii, suggesting its further purification and characterization as a novel biological pest management tool against aphids and other phloem-feeding insect pests.

Green peach aphid, Myzus persicae (Hemiptera: Aphididae), is an economically important pest of crops within more than 40 plant families all over the world. This study encompasses in-vitro pathogenicity of two strains of Beauveria bassiana (BB-72 and BB-252) and one strain of Lecanicillium lecanii (V-4) against green peach aphid (M. persicae). Using a leaf-dip method, three different bioassays were conducted comprised of filtrates and conidial concentrations of BB-72, BB-252 and V-4 fungal strains and their binary combinations. Infiltrate bioassays, 2 mL fungal filtrate of each strain was used. In conidial bioassays, three different concentrations (i.e., 1 &times, 106, 1 &times, 107 and 1 &times, 108 conidia mL&minus, 1) of each fungal strain were used, while in binary combination bioassays, LC50 and LC33 of these fungal strains were evaluated. According to the results, maximum pathogenicity against test aphids was observed at 10th day of all treatments. Both strains of B. bassiana (BB-72 and BB-252) exhibited higher mortality of aphids (up to 95 and 91%, respectively) than L. lecanii (V-4) strain (87%) in all three types of bioassays. Moreover, binary combinations of BB-72 and BB-252 strains showed significantly higher aphid mortality (94%) than other combinations. Reduced mortality in case of fungal combinations of V-4 strain might be due to the antagonistic effect of L. lecanii strain along with both strains of B. bassiana. Nevertheless, evaluation of combined pathogenicity of the fungal strains constitutes the novelty of this in-vitro study which revealed that both strains of B. bassiana (i.e., BB-72 and BB-252) are mutually compatible and can be utilized together as new biocontrol tools against destructive insect pests such as M. persicae.

This study evaluated the pathogenicity of indigenous soil isolate of Bacillus thuringiensis (Bt) strains, applied without and along with 1.0% MgCl2 salt, to Helicoverpa armigera Hübner (Lepidoptera: Noctuidae). Toxicity and effect of Bt isolate on larval development (weight) were assessed using in vitro bioassays. Six concentrations of the tested Bt with salt (i.e., 1.0 × 107, 0.5 × 105, 1.0 × 105, 1.5 × 105, and 2.0 × 105 cfu/ml), five without salt (i.e., 0.5 × 105, 1.0 × 105, 1.5 × 105, and 2.0 × 105 cfu/ml), and control were bioassayed against third-instar larvae of H. armigera under a complete randomized design (CRD), with four replications. Results revealed that both larval mortality and weight changes were significantly affected by time (F 5, 19 = 35.98; P

While earthworms’ feeding behavior has been shown to be a key driver of greenhouse gas like nitrous oxide (N 2 O) emissions for temperate species, this assessment remains to be demonstrated for tropical ones. This study constitutes a comparative assessment of the impact of different feeding strategies of tropical earthworms on their cast emissions of N 2 O and the characterization of microbial communities associated with these emission dynamics. N 2 O flux was determined in vitro from casts of 2 epigeic ( Dichogaster annae and Eisenia andrei ) and 4 endogeic/epiendogeic ( Metaphire houlleti , Octolasion tyrtaeum , Pontoscolex corethrurus and Amynthas corticis ) earthworm species in the presence or absence of acetylene. Casts of epigeic earthworms, fed on fresh coffee pulp, emitted about 392-fold higher amounts of N 2 O than those of endogeic ones, fed on a tropical soil. Acetylene exposure significantly increased the cast emission rates indicating that (i) apart from N 2 O, dinitrogen (N 2 ) is also emitted by earthworm casts, particularly by the epigeic guild (45%) and (ii) denitrification is the major microbial process responsible for these N-gas emissions from casts. Total bacteria were 10-fold higher in epigeic casts than endogeic but the relative abundance of nitrifier (AOB) and denitrifiers (nirK and nirS) was many times higher in endogeic casts than epigeic ones. The relative gene density of nosZ to (nirK + nirS) was 4-fold higher in epigeic casts than endogeic ones. Moreover, bacterial amoA gene abundance was higher in casts of all species than for their archaeal counterparts. Cast N 2 O emission was positively correlated with nitrifier as well as denitrifier gene abundance, while it was positively correlated with epigeic nitrate and negatively with endogeic nitrate contents. Ammonium contents did not show any relationship with cast emissions. Mean ammonium and nitrate contents were many times higher in casts than food substrates except nitrate in endogeic casts which was 4-fold less than parent food substrate.

Elicitors are biofactors that induce resistance in plants against different insect pests. This in vitro study evaluated the impact of a novel elicitor protein PeBC1, extracted from a necrotrophic fungus Botrytis cinerea, on the development and fecundity parameters of green peach aphid (Myzus persicae) on common beans (Phaseolus vulgaris L.). Three different concentrations of PeBC1 elicitor (i.e., 33.56, 25.43, 19.33 &micro, g mL&minus, 1) were applied at three different temperature regimes (i.e., 18, 21, and 25 &deg, C). Elicitor treatments were applied topically on the bean plants at 3-leaf stage and newly emerged (0&ndash, 6 h old) apterous adult aphids were exposed to these treated leaves. In addition to the biological parameters of aphids, the relative expression levels of key genes associated with jasmonic acid (JA) and salicylic acid (SA) plant defense pathways were also determined through RT-qPCR. Results of bioassays revealed that the application of PeBC1 elicitor protein exhibited pronounced and significant (p &lt, 0.05) sub-lethal effects on green peach aphids. The fecundity was reduced and the nymphal development time was prolonged by different concentrations of PeBC1 elicitor and temperature regimes. Gene expression studies showed that the exogenous application of PeBC1 induced a significant upregulation of the expression levels of JA and SA pathway-associated genes in bean plants. As compared to control, elicitor-treated plants exhibited an induced resistance against aphids. Our findings suggest the potential use of PeBC1 elicitor protein in future bio-intensive management strategies against sap-sucking insect pests such as green peach aphids.

The relationship between drying and hygroscopic ability of Crateva adansonii and Populus deltoides woods to resist feeding by Odontotermes obesus was studied. Woods were dried under the sun and in the oven for a range of 5-25 days and then these were exposed to termites for 25 days in underground pits in Randomized Complete Block Design pattern with five replications. Results showed that lowest moisture gain was observed at a short time for drying with each method. Weight loss after termites’ exposure was more in less dried sap and heartwood of either plant species. The practical implication of these results is discussed.