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Entomopathogenic fungi (EPF) represent the future of pest control, as they have the capacity to induce serious infections in insects, trigger epizootics, and effectively manage insect populations. The study aimed to identify and test indigenous EPF isolates against Tribolium confusum using soil samples from Northwestern and central Saudi Arabia. Galleria mellonella larvae were used as insect bait to collect EPF from soil samples from date palm groves, fruit groves, and maise fields. Only 27.3% of soil samples tested positive for palm grove-originating EPFs. Polymerase chain reaction (PCR) identified the cultured fungi as Metarhizium anisopliae and Beauveria bassiana. Tribolium confusum pathogenicity was assessed using nine local fungal isolates. Different fungus isolates were tested for their pathogenicity on larval and adult T. confusum. The results showed that M. anisopliae MaSA-2, MaSA-3, and MaSA-4 had infection rates of 85%, 85%, and 75%, respectively, in last-instar T. confusum larvae and 5%, 10%, and 20% in adults within seven days. On the other hand, B. bassiana BbSA-4 showed a 100% infection rate in T. confusum larvae, while BbSA-5, BbSA6, BbSA-7, BbSA-8, and BbSA-9 had infection rates of 70%, 80%, 80%, 75%, and 95%, respectively. In terms of adult mortality rates, B. bassiana BbSA-4, BbSA-5, BbSA-6, BbSA-7, BbSA-8, and BbSA-9 had rates of 25%, 35%, 35%, 20%, 20%, and 40%, respectively. The research findings show that indigenous B. bassiana and M. anisopliae fungus isolates successfully eliminated T. confusum larvae, although their effectiveness against adults was limited. [ABSTRACT FROM AUTHOR]

Dusky cotton bug (DCB), Oxycarenus hyalinipennis, a serious economic sucking insect pest of cotton, is a cosmopolitan polyphagous pest with the potency to develop resistance against insecticides. The resistance was evaluated against insecticides of different chemical nature against DCB population from three cotton fields i.e., unsprayed population (Un-sp), field exposed to sucking sprays (SSp) and field exposed to bollworms sprays (BSp) using semi-opened bolls dip method. The DCB population showed differential range of resistance level against tested insecticides. These RR ratios were among susceptibility (1 fold) and tolerance to low resistance (2-10 fold) for all tested insecticides except for deltamethrin with moderate resistance (11-30 fold) for the populations of both sprayed fields. In the order of resistance for the SSp population, deltamethrin (24.4 fold) was followed by imidacloprid (6.4 fold), profenofos (4.0 fold), cypermethrin (3.2), endosulfan (2.8 fold), chlorfenapyr (2.7 fold) and chlothianidin (2.5 fold). For BSp population, RR ratios from high to low were: deltamethrin (21.2 fold) followed by imidacloprid (4.9 fold), chlothianidin (3.7 fold), cypermethrin (2.8 fold), endosulfan (2.7 fold), triazophos (2.4 fold) and profenofos (2.2 fold). Acephate was highly effective with least LC50 followed by spinosad and dimethoate, whereas, lambdacyhalothrin was least effective. Relative toxicity (RT) order from high to low for SSp population was acephate (1.00) followed by spinosad (1.33), chlorfenapyr (2.69), acetamiprid (2.77) and dimethoate (2.85). For BSp population, RT were sequenced as acephate (1.00) followed by spinosad (1.46), chlorfenapyr (1.67) and dimethoate (3.32). In control unsprayed population, RT were in order as acephate < deltamethrin < spinosad < chlorfenapyr (1.0, 1.20, 1.28 and 1.58, respectively). Lambdacyhalothrin was the least toxic against DCB population of all tested fields. From results, it can be suggested that regular insecticide resistance monitoring is crucial to avoid incidence(s) in O. hyalinipennis, and to adopt the rotational application of appropriate insecticides. [ABSTRACT FROM AUTHOR]

Differential proteomics is considered as one of the most powerful tools for evaluating relative expression of molecular moieties either in plants or animals. The present study focuses first on optimizing a rapid and sensitive protocol for the isolation of high quality protein to be used in two dimensional gel electrophoresis (2DE) from date palm samples, and then comparing differentially expressed peptides associated with red palm weevil (RPW) infestation of this plant using uninfested plants as control. Among the several methodologies we used for optimization, it was revealed that Phenol/ SDS extraction followed by methanolic ammonium acetate precipitation (designated as protocol 3 in this study) yielded high quality protein. Moreover, 2DE protein analysis demonstrated both qualitative and quantitative differences between control and infested date palm samples. Our differential proteomic methodologies showed 22 differential spots having modulation level ≥1.5 fold. Subsequently, these differentially expressed peptides were subjected to MALDI-TOF peptide mass fingerprinting analysis for their characterization. The 11 peptides identified through these methodologies fall into three major functional groups including stress/defense (5), photosynthesis (2), ion transport (1) related proteins and three with other functions. Our data revealed that proteins related to date palm defense or stress response were up-regulated in infested samples while the proteins involved in photosynthetic activities were down regulated. The present results indicated that RPW infestation of date palm plants induced molecular changes manifested through differential expression of proteins. Differentially expressed peptides besides increasing our understanding relevant to RPW infestation will help us in developing methodologies for early detection of RPW infestation beneficial for curbing this problem in economically important date palm trees. [ABSTRACT FROM AUTHOR]

Ephestia cautella (Walker) is a serious pest of dates both in the field and under storage conditions. The control of stored product pests and especially those of food products by manipulating temperature would be the best and safe choice. In this study, we examined the effects of temperature on developmental traits of E. cautella under laboratory conditions. For this study, newly hatched E. cautella larvae were reared at 25°C and 35°C, with 65 ± 5% relative humidity and a photoperiod of 15:9 (L:D). Biological parameters studied were: number and duration of larval instars; survival rate of larvae, pupae, and adults; total life span; and fecundity and fertility. Temperature had a significant impact on E. cautella development. At 5°C, there was 100% mortality; eggs failed to hatch, and no larval or pupal survival was observed. On the other hand, E. cautella pupated after five larval instars at 25°C while six instars were observed at 35°C. The larval period significantly increased at 35°C. However, total lifespan of both sexes was considerably longer at 25°C. Of the three temperatures studied, 25°C was highly favorable for fecundity, egg hatchability, and overall survival of all life stages. Complete mortality at 5°C indicated that storage at lower temperatures can prevent the storage losses inflicted by E. cautella. [ABSTRACT FROM AUTHOR]

Palm weevils (Coleoptera: Curculionidae) are the most destructive pest of many palm species worldwide, including Indonesia. Accurate species identification and knowledge of their diversity is crucial for implementing management strategies. Some samples of palm weevils from six main islands of Indonesia were found exhibiting intermediate color and markings between those of Asiatic palm weevil (APW), Rhynchophorus vulneratus Panzer and red palm weevil (RPW), R. ferrugineus (Olivier). To test the hypothesis that intermediate occurring phenotypes in Indonesia are only phenotypic color variations of APW, morphometric analyses, mating trials, and the analysis of cytochrome b (CyB) and random amplified polymorphism DNA (RAPD-PCR) were carried out. Additionally, RPW from the Kingdom of Saudi Arabia (KSA) and Pakistan were compared to Indonesian samples. Morphology-based identification of Indonesian palm weevils recognized three putative taxa: R. ferrugineus, R. vulneratus, and the black palm weevil, R. bilineatus (Montrouzier). It was suspected that intermediate color phenotypes of APW from Indonesia had been ambiguously considered RPW. Discriminant function analysis of morphometric measurements indicated that an intermediate weevil, which was previously determined to be RPW, are highly similar to APW. The mating trials of intermediate weevils and APW produced fertile progenies for three successive generations. The CyB and RAPD-PCR analyses showed that the intermediate phenotypes previously identified as RPW are distinguishable from RPW from the KSA. Therefore, our findings indicate that these are color phenotypes of APW. Thus, based on the palm weevil samples in this study, only two species exist, namely, R. vulneratus and R. bilineatus. [ABSTRACT FROM AUTHOR]

A state of the art proteomic methodology using Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI TOF) has been employed to characterize peptides modulated in the date palm stem subsequent to infestation with red palm weevil (RPW). Our analyses revealed 32 differentially expressed peptides associated with RPW infestation in date palm stem. To identify RPW infestation associated peptides (I), artificially wounded plants (W) were used as additional control beside uninfested plants, a conventional control (C). A constant unique pattern of differential expression in infested (I), wounded (W) stem samples compared to control (C) was observed. The upregulated proteins showed relative fold intensity in order of I > W and downregulated spots trend as W > I, a quite interesting pattern. This study also reveals that artificially wounding of date palm stem affects almost the same proteins as infestation; however, relative intensity is quite lower than in infested samples both in up and downregulated spots. All 32 differentially expressed spots were subjected to MALDI-TOF analysis for their identification and we were able to match 21 proteins in the already existing databases. Relatively significant modulated expression pattern of a number of peptides in infested plants predicts the possibility of developing a quick and reliable molecular methodology for detecting plants infested with date palm.