Accessing Academic Libraries Online Resources

The present twenty-first century witnesses a tremendous change and growth in Information and Communication Technology. The e-resources in the academic libraries has enabled the teachers and students to enhance their academic as well as research activities by providing the latest information and access to world wide information. The present study focuses on the accessing level of online resources in the academic libraries by its elite clienteles mainly the students. The students of this ICT era should be provided the right information at the right time. The library services supplemented by e-resources is a great boon to the contemporary users. The present paper aims to analyse the utilization relationship and status of academic libraries with the students, and make a correlation analysis of the usage to analyse the positivity and futurity of academic libraries. This study is limited within the graduate level students of the three respective institutions taken for study i.e., arts and science colleges in Tuticorin District. The study has been carried out among the students belonging to the academic year 2018-2019. The study is mainly an analytical and descriptive study based on the response of the student

Waveform Library for Chinch Bugs (Hemiptera: Heteroptera: Blissidae): Characterization of Electrical Penetration Graph Waveforms at Multiple Input Impedances

Electrical penetration graph (EPG) monitoring has been used extensively to elucidate mechanisms of resistance in plants to insect herbivores with piercing-sucking mouthparts. Characterization of waveforms produced by insects during stylet probing is essential to the application of this technology. In the studies described herein, a four-channel Backus and Bennett AC-DC monitor was used to characterize EPG waveforms produced by adults of two economically important chinch bug species: southern chinch bug, Blissus insularis Barber, feeding on St. Augustinegrass, and western chinch bug, Blissus occiduus Barber, feeding on buffalograss. This is only the third time a heteropterans species has been recorded by using EPG; it is also the first recording of adult heteropterans, and the first of Blissidae. Probing of chinch bugs was recorded with either AC or DC applied voltage, no applied voltage, or voltage switched between AC and DC mid-recording, at input impedances ranging from 106 to 1010Ω, plus 1013 Ω, to develop a waveform library. Waveforms exhibited by western and southern chinch bugs were similar, and both showed long periods of putative pathway and ingestion phases (typical of salivary sheath feeders) interspersed with shorter phases, termed transitional J wave and interruption. The J wave is suspected to be an X wave, that is, in EPG parlance, a stereotypical transition waveform that marks contact with a preferred ingestion tissue. The flexibility of using multiple input impedances with the AC-DC monitor was valuable for determining the electrical origin (resistance vs. electromotive force components) of the chinch bug waveforms. It was concluded that an input impedance of 107Ω, with either DC or AC applied voltage, is optimal to detect all resistance- and electromotive force–component waveforms produced during chinch bug probing. Knowledge of electrical origins suggested hypothesized biological meanings of the waveforms, before time-intensive future correlation experiments by using histology, microscopy, and other techniques

Microbial Production of Amylase from Cassava Waste

Bacterium mura was isolated from cassava waste, (Tamil Nadu, India) for the production of extracellular amylase. On screening for amylase producing bacteria, 5 isolates showed positive results, of which Bacterium mura showed best amylase activity. The optimal conditions for the amylase activity were found at pH 6.0 (39 U/ml) and at temperature 37°C. Amylase activity was found to be higher when lactose (31 U/ml), casein, barley (42 U/ml) and SDS (32 U/ml) were used as the carbon source, nitrogen source, agro waste source and as additives respectively. The enzyme was partially purified by dialysis and the molecular mass was found to be 65kDa by SDS-PAGE. The partially purified and crude amylase was confirmed by zymogram. The partially purified amylase was used in bread making, which improved the softening of the bread and was used as a de-sizing agent

RNAi as a management tool for the western corn rootworm, \u3ci\u3eDiabrotica virgifera virgifera\u3c/i\u3e

The western corn rootworm (WCR), Diabrotica virgifera virgifera, is the most important pest of corn in the US Corn Belt. Economic estimates indicate that costs of control and yield loss associated with WCR damage exceed $US 1 billion annually. Historically, corn rootworm management has been extremely difficult because of its ability to evolve resistance to both chemical insecticides and cultural control practices. Since 2003, the only novel commercialized developments in rootworm management have been transgenic plants expressing Bt insecticidal proteins. Four transgenic insecticidal proteins are currently registered for rootworm management, and field resistance to proteins from the Cry3 family highlights the importance of developing traits with new modes of action. One of the newest approaches for controlling rootworm pests involves RNA interference (RNAi). This review describes the current understanding of the RNAi mechanisms in WCR and the use of this technology for WCR management. Further, the review addresses ecological risk assessment of RNAi and insect resistance management of RNAi for corn rootworm

RNAi as a management tool for the western corn rootworm, \u3ci\u3eDiabrotica virgifera virgifera\u3c/i\u3e

The western corn rootworm (WCR), Diabrotica virgifera virgifera, is the most important pest of corn in the US Corn Belt. Economic estimates indicate that costs of control and yield loss associated with WCR damage exceed $US 1 billion annually. Historically, corn rootworm management has been extremely difficult because of its ability to evolve resistance to both chemical insecticides and cultural control practices. Since 2003, the only novel commercialized developments in rootworm management have been transgenic plants expressing Bt insecticidal proteins. Four transgenic insecticidal proteins are currently registered for rootworm management, and field resistance to proteins from the Cry3 family highlights the importance of developing traits with new modes of action. One of the newest approaches for controlling rootworm pests involves RNA interference (RNAi). This review describes the current understanding of the RNAi mechanisms in WCR and the use of this technology for WCR management. Further, the review addresses ecological risk assessment of RNAi and insect resistance management of RNAi for corn rootworm

RNAi induced knockdown of a cadherin-like protein (EF531715) does not affect toxicity of Cry34/35Ab1 or Cry3Aa to \u3ci\u3eDiabrotica virgifera virgifera\u3c/i\u3e larvae (Coleoptera: Chrysomelidae)

The western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, is an important maize pest throughout most of the U.S. Corn Belt. Bacillus thuringiensis (Bt) insecticidal proteins including modified Cry3Aa and Cry34/35Ab1 have been expressed in transgenic maize to protect against WCR feeding damage. To date, there is limited information regarding the WCR midgut target sites for these proteins. In this study, we examined whether a cadherin-like gene from Diabrotica virgifera virgifera (DvvCad; Gen-Bank accession # EF531715) associated with WCR larval midgut tissue is necessary for Cry3Aa or Cry34/ 35Ab1 toxicity. Experiments were designed to examine the sensitivity of WCR to trypsin activated Cry3Aa and Cry34/35Ab1 after oral feeding of the DvvCad dsRNA to knockdown gene expression. Quantitative real-time PCR confirmed that DvvCad mRNA transcript levels were reduced in larvae treated with cadherin dsRNA. Relative cadherin expression by immunoblot analysis and nano-liquid chromatography–mass spectrometry (nanoLC-MS) of WCR neonate brush border membrane vesicle (BBMV) preparations exposed to DvvCad dsRNA confirmed reduced cadherin expression when compared to BBMV from untreated larvae. However, the larval mortality and growth inhibition of WCR neonates exposed to cadherin dsRNA for two days followed by feeding exposure to either Cry3Aa or Cry34/35Ab1 for four days was not significantly different to that observed in insects exposed to either Cry3Aa or Cry34/35Ab1 alone. In combination, these results suggest that cadherin is unlikely to be involved in the toxicity of Cry3Aa or Cry34/35Ab1 to WCR

Gene silencing in \u3ci\u3eTribolium castaneum\u3c/i\u3e as a tool for the targeted identification of candidate RNAi targets in crop pests

RNAi shows potential as an agricultural technology for insect control, yet, a relatively low number of robust lethal RNAi targets have been demonstrated to control insects of agricultural interest. In the current study, a selection of lethal RNAi target genes from the iBeetle (Tribolium castaneum) screen were used to demonstrate efficacy of orthologous targets in the economically important coleopteran pests Diabrotica virgifera virgifera and Meligethes aeneus. Transcript orthologs of 50 selected genes were analyzed in D. v. virgifera diet-based RNAi bioassays; 21 of these RNAi targets showed mortality and 36 showed growth inhibition. Low dose injection- and diet-based dsRNA assays in T. castaneum and D. v. virgifera, respectively, enabled the identification of the four highly potent RNAi target genes: Rop, dre4, ncm, and RpII140. Maize was genetically engineered to express dsRNA directed against these prioritized candidate target genes. T0 plants expressing Rop, dre4, or RpII140 RNA hairpins showed protection from D. v. virgifera larval feeding damage. dsRNA targeting Rop, dre4, ncm, and RpII140 in M. aeneus also caused high levels of mortality both by injection and feeding. In summary, high throughput systems for model organisms can be successfully used to identify potent RNA targets for difficult-to-work with agricultural insect pests

Control of western corn rootworm via RNAi traits in maize: Lethal and sublethal effects of Sec23 dsRNA

Background: RNA interference (RNAi) triggered by maize plants expressing RNA hairpins against specific western corn rootworm ( WCR) transcripts have proven to be effective at controlling this pest. To provide robust crop protection, mRNA transcripts targeted by double-stranded RNA must be sensitive to knockdown and encode essential proteins. Results: Using WCR adult feeding assays, we identified Sec23 as a highly lethal RNAi target. Sec23 encodes a coatomer protein, a component of the coat protein (COPII) complex that mediates ER-Golgi transport. The lethality detected in WCR adults was also observed in early instar larvae, the life stage causing most of the crop damage, suggesting that WCR adults can serve as an alternative to larvae for dsRNA screening. Surprisingly, over 85% transcript inhibition resulted in less than 40% protein knockdown, suggesting that complete protein knockdown is not necessary for Sec23 RNAi-mediated mortality. The efficacy of Sec23 dsRNA for rootworm control was confirmed in planta; T0maize events carrying rootwormSec23 hairpin transgenes showed high levels of root protection in greenhouse assays. A reduction in larval survival and weight were observed in the offspring of WCR females exposed to Sec23 dsRNA LC25in diet bioassays. Conclusion: We describe Sec23 as RNAi target for in planta rootworm control. High mortality in exposed adult and larvae and moderate sublethal effects in the offspring of females exposed to Sec23 dsRNA LC25, suggest the potential for field application of this RNAi trait and the need to factor in responses to sublethal exposure into insect resistance management programs. Includes supplemental materials

RNAi targeting of rootworm \u3ci\u3eTroponin I\u3c/i\u3e transcripts confers root protection in maize

Western corn rootworm, Diabrotica virgifera virgifera, is the major agronomically important pest of maize in the US Corn Belt. To augment the repertoire of the available dsRNA-based traits that control rootworm, we explored a potentially haplolethal gene target, wings up A (wupA), which encodes Troponin I. Troponin I, a component of the Troponin-Tropomyosin complex, is an inhibitory protein involved in muscle contraction. In situ hybridization showed that feeding on wupA-targeted dsRNAs caused systemic transcript knockdown in D. v. virgifera larvae. The knockdown of wupA transcript, and by extension Troponin I protein, led to deterioration of the striated banding pattern in larval body muscle and decreased muscle integrity. Additionally, the loss of function of the circular muscles surrounding the alimentary system led to significant accumulation of food material in the hind gut, which is consistent with a loss of peristaltic motion of the alimentary canal. In this study, we demonstrate that wupA dsRNA is lethal in D. v. virgifera larvae when fed via artificial diet, with growth inhibition of up to 50% within two days of application. Further, wupA hairpins can be stably expressed and detected in maize. Maize expressing wupA hairpins exhibit robust root protection in greenhouse bioassays, with several maize transgene integration events showing root protection equivalent to commercial insecticidal protein-expressing maize

Evaluation of Five Methods for Total DNA Extraction from Western Corn Rootworm Beetles

Background: DNA extraction is a routine step in many insect molecular studies. A variety of methods have been used to isolate DNA molecules from insects, and many commercial kits are available. Extraction methods need to be evaluated for their efficiency, cost, and side effects such as DNA degradation during extraction. Methodology/Principal Findings: From individual western corn rootworm beetles, Diabrotica virgifera virgifera, DNA extractions by the SDS method, CTAB method, DNAzol reagent, Puregene solutions and DNeasy column were compared in terms of DNA quantity and quality, cost of materials, and time consumed. Although all five methods resulted in acceptable DNA concentrations and absorbance ratios, the SDS and CTAB methods resulted in higher DNA yield (ng DNA vs. mg tissue) at much lower cost and less degradation as revealed on agarose gels. The DNeasy kit was most time-efficient but was the costliest among the methods tested. The effects of ethanol volume, temperature and incubation time on precipitation of DNA were also investigated. The DNA samples obtained by the five methods were tested in PCR for six microsatellites located in various positions of the beetle’s genome, and all samples showed successful amplifications. Conclusion/Significance: These evaluations provide a guide for choosing methods of DNA extraction from western corn rootworm beetles based on expected DNA yield and quality, extraction time, cost, and waste control. The extraction conditions for this mid-size insect were optimized. The DNA extracted by the five methods was suitable for further molecular applications such as PCR and sequencing by synthesis